A process leading to shortening and/or development of tension in muscle tissue. Muscle contraction occurs by a sliding filament mechanism whereby actin filaments slide inward among the myosin filaments.
Contractile tissue that produces movement in animals.
Unstriated and unstriped muscle, one of the muscles of the internal organs, blood vessels, hair follicles, etc. Contractile elements are elongated, usually spindle-shaped cells with centrally located nuclei. Smooth muscle fibers are bound together into sheets or bundles by reticular fibers and frequently elastic nets are also abundant. (From Stedman, 25th ed)
A subtype of striated muscle, attached by TENDONS to the SKELETON. Skeletal muscles are innervated and their movement can be consciously controlled. They are also called voluntary muscles.
Muscular contractions characterized by increase in tension without change in length.
The protein constituents of muscle, the major ones being ACTINS and MYOSINS. More than a dozen accessory proteins exist including TROPONIN; TROPOMYOSIN; and DYSTROPHIN.
The nonstriated involuntary muscle tissue of blood vessels.
Large, multinucleate single cells, either cylindrical or prismatic in shape, that form the basic unit of SKELETAL MUSCLE. They consist of MYOFIBRILS enclosed within and attached to the SARCOLEMMA. They are derived from the fusion of skeletal myoblasts (MYOBLASTS, SKELETAL) into a syncytium, followed by differentiation.
A state arrived at through prolonged and strong contraction of a muscle. Studies in athletes during prolonged submaximal exercise have shown that muscle fatigue increases in almost direct proportion to the rate of muscle glycogen depletion. Muscle fatigue in short-term maximal exercise is associated with oxygen lack and an increased level of blood and muscle lactic acid, and an accompanying increase in hydrogen-ion concentration in the exercised muscle.
Use of electric potential or currents to elicit biological responses.
Contraction of the UTERINE MUSCLE.
Developmental events leading to the formation of adult muscular system, which includes differentiation of the various types of muscle cell precursors, migration of myoblasts, activation of myogenesis and development of muscle anchorage.
Contractile activity of the MYOCARDIUM.
That phase of a muscle twitch during which a muscle returns to a resting position.
A basic element found in nearly all organized tissues. It is a member of the alkaline earth family of metals with the atomic symbol Ca, atomic number 20, and atomic weight 40. Calcium is the most abundant mineral in the body and combines with phosphorus to form calcium phosphate in the bones and teeth. It is essential for the normal functioning of nerves and muscles and plays a role in blood coagulation (as factor IV) and in many enzymatic processes.
Recording of the changes in electric potential of muscle by means of surface or needle electrodes.
Skeletal muscle fibers characterized by their expression of the Type II MYOSIN HEAVY CHAIN isoforms which have high ATPase activity and effect several other functional properties - shortening velocity, power output, rate of tension redevelopment. Several fast types have been identified.
Skeletal muscle fibers characterized by their expression of the Type I MYOSIN HEAVY CHAIN isoforms which have low ATPase activity and effect several other functional properties - shortening velocity, power output, rate of tension redevelopment.
The species Oryctolagus cuniculus, in the family Leporidae, order LAGOMORPHA. Rabbits are born in burrows, furless, and with eyes and ears closed. In contrast with HARES, rabbits have 22 chromosome pairs.
Non-striated, elongated, spindle-shaped cells found lining the digestive tract, uterus, and blood vessels. They are derived from specialized myoblasts (MYOBLASTS, SMOOTH MUSCLE).
Skeletal muscle structures that function as the MECHANORECEPTORS responsible for the stretch or myotactic reflex (REFLEX, STRETCH). They are composed of a bundle of encapsulated SKELETAL MUSCLE FIBERS, i.e., the intrafusal fibers (nuclear bag 1 fibers, nuclear bag 2 fibers, and nuclear chain fibers) innervated by SENSORY NEURONS.
The cartilaginous and membranous tube descending from the larynx and branching into the right and left main bronchi.
The resection or removal of the innervation of a muscle or muscle tissue.
A common name used for the genus Cavia. The most common species is Cavia porcellus which is the domesticated guinea pig used for pets and biomedical research.
One of two types of muscle in the body, characterized by the array of bands observed under microscope. Striated muscles can be divided into two subtypes: the CARDIAC MUSCLE and the SKELETAL MUSCLE.
Mitochondria of skeletal and smooth muscle. It does not include myocardial mitochondria for which MITOCHONDRIA, HEART is available.
The physiological narrowing of BLOOD VESSELS by contraction of the VASCULAR SMOOTH MUSCLE.
Conical muscular projections from the walls of the cardiac ventricles, attached to the cusps of the atrioventricular valves by the chordae tendineae.
The neck muscles consist of the platysma, splenius cervicis, sternocleidomastoid(eus), longus colli, the anterior, medius, and posterior scalenes, digastric(us), stylohyoid(eus), mylohyoid(eus), geniohyoid(eus), sternohyoid(eus), omohyoid(eus), sternothyroid(eus), and thyrohyoid(eus).
The long cylindrical contractile organelles of STRIATED MUSCLE cells composed of ACTIN FILAMENTS; MYOSIN filaments; and other proteins organized in arrays of repeating units called SARCOMERES .
A diverse superfamily of proteins that function as translocating proteins. They share the common characteristics of being able to bind ACTINS and hydrolyze MgATP. Myosins generally consist of heavy chains which are involved in locomotion, and light chains which are involved in regulation. Within the structure of myosin heavy chain are three domains: the head, the neck and the tail. The head region of the heavy chain contains the actin binding domain and MgATPase domain which provides energy for locomotion. The neck region is involved in binding the light-chains. The tail region provides the anchoring point that maintains the position of the heavy chain. The superfamily of myosins is organized into structural classes based upon the type and arrangement of the subunits they contain.
The muscles that move the eye. Included in this group are the medial rectus, lateral rectus, superior rectus, inferior rectus, inferior oblique, superior oblique, musculus orbitalis, and levator palpebrae superioris.
A movement, caused by sequential muscle contraction, that pushes the contents of the intestines or other tubular organs in one direction.
Neurons which activate MUSCLE CELLS.
The properties, processes, and behavior of biological systems under the action of mechanical forces.
A white crystal or crystalline powder used in BUFFERS; FERTILIZERS; and EXPLOSIVES. It can be used to replenish ELECTROLYTES and restore WATER-ELECTROLYTE BALANCE in treating HYPOKALEMIA.
The smaller subunits of MYOSINS that bind near the head groups of MYOSIN HEAVY CHAINS. The myosin light chains have a molecular weight of about 20 KDa and there are usually one essential and one regulatory pair of light chains associated with each heavy chain. Many myosin light chains that bind calcium are considered "calmodulin-like" proteins.
A protein found in the thin filaments of muscle fibers. It inhibits contraction of the muscle unless its position is modified by TROPONIN.
Either of two extremities of four-footed non-primate land animals. It usually consists of a FEMUR; TIBIA; and FIBULA; tarsals; METATARSALS; and TOES. (From Storer et al., General Zoology, 6th ed, p73)
Elements of limited time intervals, contributing to particular results or situations.
These include the muscles of the DIAPHRAGM and the INTERCOSTAL MUSCLES.
Muscle contraction with negligible change in the force of contraction but shortening of the distance between the origin and insertion.
A vague complaint of debility, fatigue, or exhaustion attributable to weakness of various muscles. The weakness can be characterized as subacute or chronic, often progressive, and is a manifestation of many muscle and neuromuscular diseases. (From Wyngaarden et al., Cecil Textbook of Medicine, 19th ed, p2251)
Muscles forming the ABDOMINAL WALL including RECTUS ABDOMINIS, external and internal oblique muscles, transversus abdominis, and quadratus abdominis. (from Stedman, 25th ed)
A neurotransmitter found at neuromuscular junctions, autonomic ganglia, parasympathetic effector junctions, a subset of sympathetic effector junctions, and at many sites in the central nervous system.
Filamentous proteins that are the main constituent of the thin filaments of muscle fibers. The filaments (known also as filamentous or F-actin) can be dissociated into their globular subunits; each subunit is composed of a single polypeptide 375 amino acids long. This is known as globular or G-actin. In conjunction with MYOSINS, actin is responsible for the contraction and relaxation of muscle.
The quadriceps femoris. A collective name of the four-headed skeletal muscle of the thigh, comprised of the rectus femoris, vastus intermedius, vastus lateralis, and vastus medialis.
A strain of albino rat used widely for experimental purposes because of its calmness and ease of handling. It was developed by the Sprague-Dawley Animal Company.
The repeating contractile units of the MYOFIBRIL, delimited by Z bands along its length.
One of the three polypeptide chains that make up the TROPONIN complex of skeletal muscle. It is a calcium-binding protein.
A strain of albino rat developed at the Wistar Institute that has spread widely at other institutions. This has markedly diluted the original strain.
Mature contractile cells, commonly known as myocytes, that form one of three kinds of muscle. The three types of muscle cells are skeletal (MUSCLE FIBERS, SKELETAL), cardiac (MYOCYTES, CARDIAC), and smooth (MYOCYTES, SMOOTH MUSCLE). They are derived from embryonic (precursor) muscle cells called MYOBLASTS.
Muscles of facial expression or mimetic muscles that include the numerous muscles supplied by the facial nerve that are attached to and move the skin of the face. (From Stedman, 25th ed)
The relationship between the dose of an administered drug and the response of the organism to the drug.
The motor activity of the GASTROINTESTINAL TRACT.
The rotational force about an axis that is equal to the product of a force times the distance from the axis where the force is applied.
A musculomembranous sac along the URINARY TRACT. URINE flows from the KIDNEYS into the bladder via the ureters (URETER), and is held there until URINATION.
Muscles arising in the zygomatic arch that close the jaw. Their nerve supply is masseteric from the mandibular division of the trigeminal nerve. (From Stedman, 25th ed)
A group of intracellular-signaling serine threonine kinases that bind to RHO GTP-BINDING PROTEINS. They were originally found to mediate the effects of rhoA GTP-BINDING PROTEIN on the formation of STRESS FIBERS and FOCAL ADHESIONS. Rho-associated kinases have specificity for a variety of substrates including MYOSIN-LIGHT-CHAIN PHOSPHATASE and LIM KINASES.
The state of activity or tension of a muscle beyond that related to its physical properties, that is, its active resistance to stretch. In skeletal muscle, tonus is dependent upon efferent innervation. (Stedman, 25th ed)
The musculofibrous partition that separates the THORACIC CAVITY from the ABDOMINAL CAVITY. Contraction of the diaphragm increases the volume of the thoracic cavity aiding INHALATION.
The synapse between a neuron and a muscle.
Drugs used to cause constriction of the blood vessels.
The domestic dog, Canis familiaris, comprising about 400 breeds, of the carnivore family CANIDAE. They are worldwide in distribution and live in association with people. (Walker's Mammals of the World, 5th ed, p1065)
The domestic cat, Felis catus, of the carnivore family FELIDAE, comprising over 30 different breeds. The domestic cat is descended primarily from the wild cat of Africa and extreme southwestern Asia. Though probably present in towns in Palestine as long ago as 7000 years, actual domestication occurred in Egypt about 4000 years ago. (From Walker's Mammals of the World, 6th ed, p801)
Expenditure of energy during PHYSICAL ACTIVITY. Intensity of exertion may be measured by rate of OXYGEN CONSUMPTION; HEAT produced, or HEART RATE. Perceived exertion, a psychological measure of exertion, is included.
A protein complex of actin and MYOSINS occurring in muscle. It is the essential contractile substance of muscle.
An alpha-1 adrenergic agonist used as a mydriatic, nasal decongestant, and cardiotonic agent.
A powerful flexor of the thigh at the hip joint (psoas major) and a weak flexor of the trunk and lumbar spinal column (psoas minor). Psoas is derived from the Greek "psoa", the plural meaning "muscles of the loin". It is a common site of infection manifesting as abscess (PSOAS ABSCESS). The psoas muscles and their fibers are also used frequently in experiments in muscle physiology.
One of the minor protein components of skeletal muscle. Its function is to serve as the calcium-binding component in the troponin-tropomyosin B-actin-myosin complex by conferring calcium sensitivity to the cross-linked actin and myosin filaments.
Theoretical representations that simulate the behavior or activity of biological processes or diseases. For disease models in living animals, DISEASE MODELS, ANIMAL is available. Biological models include the use of mathematical equations, computers, and other electronic equipment.
An adenine nucleotide containing three phosphate groups esterified to the sugar moiety. In addition to its crucial roles in metabolism adenosine triphosphate is a neurotransmitter.
The distal and narrowest portion of the SMALL INTESTINE, between the JEJUNUM and the ILEOCECAL VALVE of the LARGE INTESTINE.
An involuntary movement or exercise of function in a part, excited in response to a stimulus applied to the periphery and transmitted to the brain or spinal cord.
Cells propagated in vitro in special media conducive to their growth. Cultured cells are used to study developmental, morphologic, metabolic, physiologic, and genetic processes, among others.
A masticatory muscle whose action is closing the jaws.
Precursor of epinephrine that is secreted by the adrenal medulla and is a widespread central and autonomic neurotransmitter. Norepinephrine is the principal transmitter of most postganglionic sympathetic fibers and of the diffuse projection system in the brain arising from the locus ceruleus. It is also found in plants and is used pharmacologically as a sympathomimetic.
Acquired, familial, and congenital disorders of SKELETAL MUSCLE and SMOOTH MUSCLE.
Respiratory muscles that arise from the lower border of one rib and insert into the upper border of the adjoining rib, and contract during inspiration or respiration. (From Stedman, 25th ed)
A methylxanthine naturally occurring in some beverages and also used as a pharmacological agent. Caffeine's most notable pharmacological effect is as a central nervous system stimulant, increasing alertness and producing agitation. It also relaxes SMOOTH MUSCLE, stimulates CARDIAC MUSCLE, stimulates DIURESIS, and appears to be useful in the treatment of some types of headache. Several cellular actions of caffeine have been observed, but it is not entirely clear how each contributes to its pharmacological profile. Among the most important are inhibition of cyclic nucleotide PHOSPHODIESTERASES, antagonism of ADENOSINE RECEPTORS, and modulation of intracellular calcium handling.
The introduction of a phosphoryl group into a compound through the formation of an ester bond between the compound and a phosphorus moiety.
An enzyme that phosphorylates myosin light chains in the presence of ATP to yield myosin-light chain phosphate and ADP, and requires calcium and CALMODULIN. The 20-kDa light chain is phosphorylated more rapidly than any other acceptor, but light chains from other myosins and myosin itself can act as acceptors. The enzyme plays a central role in the regulation of smooth muscle contraction.
An alkaloid, originally from Atropa belladonna, but found in other plants, mainly SOLANACEAE. Hyoscyamine is the 3(S)-endo isomer of atropine.
The muscle tissue of the HEART. It is composed of striated, involuntary muscle cells (MYOCYTES, CARDIAC) connected to form the contractile pump to generate blood flow.
The portion of the descending aorta proceeding from the arch of the aorta and extending to the DIAPHRAGM, eventually connecting to the ABDOMINAL AORTA.
The recording of muscular movements. The apparatus is called a myograph, the record or tracing, a myogram. (From Stedman, 25th ed)
A purely physical condition which exists within any material because of strain or deformation by external forces or by non-uniform thermal expansion; expressed quantitatively in units of force per unit area.
An element in the alkali group of metals with an atomic symbol K, atomic number 19, and atomic weight 39.10. It is the chief cation in the intracellular fluid of muscle and other cells. Potassium ion is a strong electrolyte that plays a significant role in the regulation of fluid volume and maintenance of the WATER-ELECTROLYTE BALANCE.
Derangement in size and number of muscle fibers occurring with aging, reduction in blood supply, or following immobilization, prolonged weightlessness, malnutrition, and particularly in denervation.
Fibers composed of MICROFILAMENT PROTEINS, which are predominately ACTIN. They are the smallest of the cytoskeletal filaments.
Compounds or agents that combine with an enzyme in such a manner as to prevent the normal substrate-enzyme combination and the catalytic reaction.
The rate dynamics in chemical or physical systems.
The larger subunits of MYOSINS. The heavy chains have a molecular weight of about 230 kDa and each heavy chain is usually associated with a dissimilar pair of MYOSIN LIGHT CHAINS. The heavy chains possess actin-binding and ATPase activity.
Drugs that bind to and activate cholinergic receptors.
Signal transduction mechanisms whereby calcium mobilization (from outside the cell or from intracellular storage pools) to the cytoplasm is triggered by external stimuli. Calcium signals are often seen to propagate as waves, oscillations, spikes, sparks, or puffs. The calcium acts as an intracellular messenger by activating calcium-responsive proteins.
A phosphoprotein phosphatase that is specific for MYOSIN LIGHT CHAINS. It is composed of three subunits, which include a catalytic subunit, a myosin binding subunit, and a third subunit of unknown function.
The main trunk of the systemic arteries.
The intracellular transfer of information (biological activation/inhibition) through a signal pathway. In each signal transduction system, an activation/inhibition signal from a biologically active molecule (hormone, neurotransmitter) is mediated via the coupling of a receptor/enzyme to a second messenger system or to an ion channel. Signal transduction plays an important role in activating cellular functions, cell differentiation, and cell proliferation. Examples of signal transduction systems are the GAMMA-AMINOBUTYRIC ACID-postsynaptic receptor-calcium ion channel system, the receptor-mediated T-cell activation pathway, and the receptor-mediated activation of phospholipases. Those coupled to membrane depolarization or intracellular release of calcium include the receptor-mediated activation of cytotoxic functions in granulocytes and the synaptic potentiation of protein kinase activation. Some signal transduction pathways may be part of larger signal transduction pathways; for example, protein kinase activation is part of the platelet activation signal pathway.
A network of tubules and sacs in the cytoplasm of SKELETAL MUSCLE FIBERS that assist with muscle contraction and relaxation by releasing and storing calcium ions.
A type of stress exerted uniformly in all directions. Its measure is the force exerted per unit area. (McGraw-Hill Dictionary of Scientific and Technical Terms, 6th ed)
Abrupt changes in the membrane potential that sweep along the CELL MEMBRANE of excitable cells in response to excitation stimuli.
Fibrous bands or cords of CONNECTIVE TISSUE at the ends of SKELETAL MUSCLE FIBERS that serve to attach the MUSCLES to bones and other structures.
Myosin type II isoforms found in smooth muscle.
A biochemical messenger and regulator, synthesized from the essential amino acid L-TRYPTOPHAN. In humans it is found primarily in the central nervous system, gastrointestinal tract, and blood platelets. Serotonin mediates several important physiological functions including neurotransmission, gastrointestinal motility, hemostasis, and cardiovascular integrity. Multiple receptor families (RECEPTORS, SEROTONIN) explain the broad physiological actions and distribution of this biochemical mediator.
A potent vasodilator agent with calcium antagonistic action. It is a useful anti-anginal agent that also lowers blood pressure.
Reflex contraction of a muscle in response to stretching, which stimulates muscle proprioceptors.
Elongated, spindle-shaped, quiescent myoblasts lying in close contact with adult skeletal muscle. They are thought to play a role in muscle repair and regeneration.
The flow of BLOOD through or around an organ or region of the body.
The voltage differences across a membrane. For cellular membranes they are computed by subtracting the voltage measured outside the membrane from the voltage measured inside the membrane. They result from differences of inside versus outside concentration of potassium, sodium, chloride, and other ions across cells' or ORGANELLES membranes. For excitable cells, the resting membrane potentials range between -30 and -100 millivolts. Physical, chemical, or electrical stimuli can make a membrane potential more negative (hyperpolarization), or less negative (depolarization).
A class of drugs that act by selective inhibition of calcium influx through cellular membranes.
The inferior part of the lower extremity between the KNEE and the ANKLE.
A stable prostaglandin endoperoxide analog which serves as a thromboxane mimetic. Its actions include mimicking the hydro-osmotic effect of VASOPRESSIN and activation of TYPE C PHOSPHOLIPASES. (From J Pharmacol Exp Ther 1983;224(1): 108-117; Biochem J 1984;222(1):103-110)
The act, process, or result of passing from one place or position to another. It differs from LOCOMOTION in that locomotion is restricted to the passing of the whole body from one place to another, while movement encompasses both locomotion but also a change of the position of the whole body or any of its parts. Movement may be used with reference to humans, vertebrate and invertebrate animals, and microorganisms. Differentiate also from MOTOR ACTIVITY, movement associated with behavior.
Physical activity which is usually regular and done with the intention of improving or maintaining PHYSICAL FITNESS or HEALTH. Contrast with PHYSICAL EXERTION which is concerned largely with the physiologic and metabolic response to energy expenditure.
An amine derived by enzymatic decarboxylation of HISTIDINE. It is a powerful stimulant of gastric secretion, a constrictor of bronchial smooth muscle, a vasodilator, and also a centrally acting neurotransmitter.
The vessels carrying blood away from the heart.
The muscular membranous segment between the PHARYNX and the STOMACH in the UPPER GASTROINTESTINAL TRACT.
An endogenous substance found mainly in skeletal muscle of vertebrates. It has been tried in the treatment of cardiac disorders and has been added to cardioplegic solutions. (Reynolds JEF(Ed): Martindale: The Extra Pharmacopoeia (electronic version). Micromedex, Inc, Englewood, CO, 1996)
The pectoralis major and pectoralis minor muscles that make up the upper and fore part of the chest in front of the AXILLA.
An order of the class Amphibia, which includes several families of frogs and toads. They are characterized by well developed hind limbs adapted for jumping, fused head and trunk and webbed toes. The term "toad" is ambiguous and is properly applied only to the family Bufonidae.
The hollow, muscular organ that maintains the circulation of the blood.
One of the three polypeptide chains that make up the TROPONIN complex. It inhibits F-actin-myosin interactions.
Arteries which arise from the abdominal aorta and distribute to most of the intestines.
The excretory duct of the testes that carries SPERMATOZOA. It rises from the SCROTUM and joins the SEMINAL VESICLES to form the ejaculatory duct.
The time span between the beginning of physical activity by an individual and the termination because of exhaustion.
A sustained and usually painful contraction of muscle fibers. This may occur as an isolated phenomenon or as a manifestation of an underlying disease process (e.g., UREMIA; HYPOTHYROIDISM; MOTOR NEURON DISEASE; etc.). (From Adams et al., Principles of Neurology, 6th ed, p1398)
The spread of response if stimulation is prolonged. (Campbell's Psychiatric Dictionary, 8th ed.)
The study of the generation and behavior of electrical charges in living organisms particularly the nervous system and the effects of electricity on living organisms.
The larger air passages of the lungs arising from the terminal bifurcation of the TRACHEA. They include the largest two primary bronchi which branch out into secondary bronchi, and tertiary bronchi which extend into BRONCHIOLES and PULMONARY ALVEOLI.
Parts of the myosin molecule resulting from cleavage by proteolytic enzymes (PAPAIN; TRYPSIN; or CHYMOTRYPSIN) at well-localized regions. Study of these isolated fragments helps to delineate the functional roles of different parts of myosin. Two of the most common subfragments are myosin S-1 and myosin S-2. S-1 contains the heads of the heavy chains plus the light chains and S-2 contains part of the double-stranded, alpha-helical, heavy chain tail (myosin rod).
The physiological widening of BLOOD VESSELS by relaxing the underlying VASCULAR SMOOTH MUSCLE.
The rate at which oxygen is used by a tissue; microliters of oxygen STPD used per milligram of tissue per hour; the rate at which oxygen enters the blood from alveolar gas, equal in the steady state to the consumption of oxygen by tissue metabolism throughout the body. (Stedman, 25th ed, p346)
Region of the body immediately surrounding and including the ELBOW JOINT.
RNA sequences that serve as templates for protein synthesis. Bacterial mRNAs are generally primary transcripts in that they do not require post-transcriptional processing. Eukaryotic mRNA is synthesized in the nucleus and must be exported to the cytoplasm for translation. Most eukaryotic mRNAs have a sequence of polyadenylic acid at the 3' end, referred to as the poly(A) tail. The function of this tail is not known for certain, but it may play a role in the export of mature mRNA from the nucleus as well as in helping stabilize some mRNA molecules by retarding their degradation in the cytoplasm.
The electrical response evoked in a muscle or motor nerve by electrical or magnetic stimulation. Common methods of stimulation are by transcranial electrical and TRANSCRANIAL MAGNETIC STIMULATION. It is often used for monitoring during neurosurgery.
The chemical reactions involved in the production and utilization of various forms of energy in cells.
Resistance and recovery from distortion of shape.
A methylpyrrole-carboxylate from RYANIA that disrupts the RYANODINE RECEPTOR CALCIUM RELEASE CHANNEL to modify CALCIUM release from SARCOPLASMIC RETICULUM resulting in alteration of MUSCLE CONTRACTION. It was previously used in INSECTICIDES. It is used experimentally in conjunction with THAPSIGARGIN and other inhibitors of CALCIUM ATPASE uptake of calcium into SARCOPLASMIC RETICULUM.
Descriptions of specific amino acid, carbohydrate, or nucleotide sequences which have appeared in the published literature and/or are deposited in and maintained by databanks such as GENBANK, European Molecular Biology Laboratory (EMBL), National Biomedical Research Foundation (NBRF), or other sequence repositories.
Drugs that bind to but do not activate MUSCARINIC RECEPTORS, thereby blocking the actions of endogenous ACETYLCHOLINE or exogenous agonists. Muscarinic antagonists have widespread effects including actions on the iris and ciliary muscle of the eye, the heart and blood vessels, secretions of the respiratory tract, GI system, and salivary glands, GI motility, urinary bladder tone, and the central nervous system.
Cells specialized to transduce mechanical stimuli and relay that information centrally in the nervous system. Mechanoreceptor cells include the INNER EAR hair cells, which mediate hearing and balance, and the various somatosensory receptors, often with non-neural accessory structures.
Common name for the species Gallus gallus, the domestic fowl, in the family Phasianidae, order GALLIFORMES. It is descended from the red jungle fowl of SOUTHEAST ASIA.
A masticatory muscle whose action is closing the jaws; its posterior portion retracts the mandible.
Proteins which bind calmodulin. They are found in many tissues and have a variety of functions including F-actin cross-linking properties, inhibition of cyclic nucleotide phosphodiesterase and calcium and magnesium ATPases.
An aminoperhydroquinazoline poison found mainly in the liver and ovaries of fishes in the order TETRAODONTIFORMES, which are eaten. The toxin causes paresthesia and paralysis through interference with neuromuscular conduction.
The excitable plasma membrane of a muscle cell. (Glick, Glossary of Biochemistry and Molecular Biology, 1990)
A calcium channel blocker that is a class IV anti-arrhythmia agent.
Voltage-dependent cell membrane glycoproteins selectively permeable to calcium ions. They are categorized as L-, T-, N-, P-, Q-, and R-types based on the activation and inactivation kinetics, ion specificity, and sensitivity to drugs and toxins. The L- and T-types are present throughout the cardiovascular and central nervous systems and the N-, P-, Q-, & R-types are located in neuronal tissue.
Voluntary activity without external compulsion.
A tetrameric calcium release channel in the SARCOPLASMIC RETICULUM membrane of SMOOTH MUSCLE CELLS, acting oppositely to SARCOPLASMIC RETICULUM CALCIUM-TRANSPORTING ATPASES. It is important in skeletal and cardiac excitation-contraction coupling and studied by using RYANODINE. Abnormalities are implicated in CARDIAC ARRHYTHMIAS and MUSCULAR DISEASES.
Organic compounds containing the -CO-NH2 radical. Amides are derived from acids by replacement of -OH by -NH2 or from ammonia by the replacement of H by an acyl group. (From Grant & Hackh's Chemical Dictionary, 5th ed)
A free radical gas produced endogenously by a variety of mammalian cells, synthesized from ARGININE by NITRIC OXIDE SYNTHASE. Nitric oxide is one of the ENDOTHELIUM-DEPENDENT RELAXING FACTORS released by the vascular endothelium and mediates VASODILATION. It also inhibits platelet aggregation, induces disaggregation of aggregated platelets, and inhibits platelet adhesion to the vascular endothelium. Nitric oxide activates cytosolic GUANYLATE CYCLASE and thus elevates intracellular levels of CYCLIC GMP.
Drugs that selectively bind to and activate alpha adrenergic receptors.
Measurement of the pressure or tension of liquids or gases with a manometer.
Movement or the ability to move from one place or another. It can refer to humans, vertebrate or invertebrate animals, and microorganisms.
The number of times the HEART VENTRICLES contract per unit of time, usually per minute.
The portion of the leg in humans and other animals found between the HIP and KNEE.
The smooth muscle coat of the uterus, which forms the main mass of the organ.
Benzopyrroles with the nitrogen at the number one carbon adjacent to the benzyl portion, in contrast to ISOINDOLES which have the nitrogen away from the six-membered ring.
Different forms of a protein that may be produced from different GENES, or from the same gene by ALTERNATIVE SPLICING.
The gradual irreversible changes in structure and function of an organism that occur as a result of the passage of time.
A statistical technique that isolates and assesses the contributions of categorical independent variables to variation in the mean of a continuous dependent variable.
The muscles of the PHARYNX are voluntary muscles arranged in two layers. The external circular layer consists of three constrictors (superior, middle, and inferior). The internal longitudinal layer consists of the palatopharyngeus, the salpingopharyngeus, and the stylopharyngeus. During swallowing, the outer layer constricts the pharyngeal wall and the inner layer elevates pharynx and LARYNX.
A region of the lower extremity immediately surrounding and including the KNEE JOINT.
An organ of digestion situated in the left upper quadrant of the abdomen between the termination of the ESOPHAGUS and the beginning of the DUODENUM.
A monosynaptic reflex elicited by stimulating a nerve, particularly the tibial nerve, with an electric shock.
The order of amino acids as they occur in a polypeptide chain. This is referred to as the primary structure of proteins. It is of fundamental importance in determining PROTEIN CONFORMATION.
A 21-amino acid peptide produced in a variety of tissues including endothelial and vascular smooth-muscle cells, neurons and astrocytes in the central nervous system, and endometrial cells. It acts as a modulator of vasomotor tone, cell proliferation, and hormone production. (N Eng J Med 1995;333(6):356-63)
A primary source of energy for living organisms. It is naturally occurring and is found in fruits and other parts of plants in its free state. It is used therapeutically in fluid and nutrient replacement.
The smallest divisions of the arteries located between the muscular arteries and the capillaries.
A non-steroidal anti-inflammatory agent (NSAID) that inhibits the enzyme cyclooxygenase necessary for the formation of prostaglandins and other autacoids. It also inhibits the motility of polymorphonuclear leukocytes.
An imidazole derivative which is a metabolite of the antineoplastic agents BIC and DIC. By itself, or as the ribonucleotide, it is used as a condensation agent in the preparation of nucleosides and nucleotides. Compounded with orotic acid, it is used to treat liver diseases.
The superior portion of the body of the stomach above the level of the cardiac notch.
Soft tissue formed mainly by the pelvic diaphragm, which is composed of the two levator ani and two coccygeus muscles. The pelvic diaphragm lies just below the pelvic aperture (outlet) and separates the pelvic cavity from the PERINEUM. It extends between the PUBIC BONE anteriorly and the COCCYX posteriorly.
Force exerted when gripping or grasping.
An eleven-amino acid neurotransmitter that appears in both the central and peripheral nervous systems. It is involved in transmission of PAIN, causes rapid contractions of the gastrointestinal smooth muscle, and modulates inflammatory and immune responses.
The non-genetic biological changes of an organism in response to challenges in its ENVIRONMENT.
An serine-threonine protein kinase that requires the presence of physiological concentrations of CALCIUM and membrane PHOSPHOLIPIDS. The additional presence of DIACYLGLYCEROLS markedly increases its sensitivity to both calcium and phospholipids. The sensitivity of the enzyme can also be increased by PHORBOL ESTERS and it is believed that protein kinase C is the receptor protein of tumor-promoting phorbol esters.
A process fundamental to muscle physiology whereby an electrical stimulus or action potential triggers a myocyte to depolarize and contract. This mechanical muscle contraction response is regulated by entry of calcium ions into the cell.
Embryonic (precursor) cells of the myogenic lineage that develop from the MESODERM. They undergo proliferation, migrate to their various sites, and then differentiate into the appropriate form of myocytes (MYOCYTES, SKELETAL; MYOCYTES, CARDIAC; MYOCYTES, SMOOTH MUSCLE).
Continuous involuntary sustained muscle contraction which is often a manifestation of BASAL GANGLIA DISEASES. When an affected muscle is passively stretched, the degree of resistance remains constant regardless of the rate at which the muscle is stretched. This feature helps to distinguish rigidity from MUSCLE SPASTICITY. (From Adams et al., Principles of Neurology, 6th ed, p73)
The physiologic or functional barrier to GASTROESOPHAGEAL REFLUX at the esophagogastric junction. Sphincteric muscles remain tonically contracted during the resting state and form the high-pressure zone separating the lumen of the ESOPHAGUS from that of the STOMACH. (Haubrich et al, Bockus Gastroenterology, 5th ed., pp399, 415)
Narrowing of the caliber of the BRONCHI, physiologically or as a result of pharmacological intervention.
Genetically identical individuals developed from brother and sister matings which have been carried out for twenty or more generations or by parent x offspring matings carried out with certain restrictions. This also includes animals with a long history of closed colony breeding.
Strains of mice in which certain GENES of their GENOMES have been disrupted, or "knocked-out". To produce knockouts, using RECOMBINANT DNA technology, the normal DNA sequence of the gene being studied is altered to prevent synthesis of a normal gene product. Cloned cells in which this DNA alteration is successful are then injected into mouse EMBRYOS to produce chimeric mice. The chimeric mice are then bred to yield a strain in which all the cells of the mouse contain the disrupted gene. Knockout mice are used as EXPERIMENTAL ANIMAL MODELS for diseases (DISEASE MODELS, ANIMAL) and to clarify the functions of the genes.
One of the three polypeptide chains that make up the TROPONIN complex. It is a cardiac-specific protein that binds to TROPOMYOSIN. It is released from damaged or injured heart muscle cells (MYOCYTES, CARDIAC). Defects in the gene encoding troponin T result in FAMILIAL HYPERTROPHIC CARDIOMYOPATHY.
A general term most often used to describe severe or complete loss of muscle strength due to motor system disease from the level of the cerebral cortex to the muscle fiber. This term may also occasionally refer to a loss of sensory function. (From Adams et al., Principles of Neurology, 6th ed, p45)
A subclass of muscarinic receptor that mediates cholinergic-induced contraction in a variety of SMOOTH MUSCLES.
A condition characterized by abnormal posturing of the limbs that is associated with injury to the brainstem. This may occur as a clinical manifestation or induced experimentally in animals. The extensor reflexes are exaggerated leading to rigid extension of the limbs accompanied by hyperreflexia and opisthotonus. This condition is usually caused by lesions which occur in the region of the brainstem that lies between the red nuclei and the vestibular nuclei. In contrast, decorticate rigidity is characterized by flexion of the elbows and wrists with extension of the legs and feet. The causative lesion for this condition is located above the red nuclei and usually consists of diffuse cerebral damage. (From Adams et al., Principles of Neurology, 6th ed, p358)
Agents that inhibit the actions of the parasympathetic nervous system. The major group of drugs used therapeutically for this purpose is the MUSCARINIC ANTAGONISTS.
Pentacyclic triterpene saponins, biosynthesized from protoaescigenin and barringtogenol, occurring in the seeds of AESCULUS. It inhibits edema formation and decreases vascular fragility.
The amount of force generated by MUSCLE CONTRACTION. Muscle strength can be measured during isometric, isotonic, or isokinetic contraction, either manually or using a device such as a MUSCLE STRENGTH DYNAMOMETER.
A device that measures MUSCLE STRENGTH during muscle contraction, such as gripping, pushing, and pulling. It is used to evaluate the health status of muscle in sports medicine or physical therapy.
Drugs used to cause dilation of the blood vessels.
The artery formed by the union of the right and left vertebral arteries; it runs from the lower to the upper border of the pons, where it bifurcates into the two posterior cerebral arteries.
One of the two major classes of cholinergic receptors. Muscarinic receptors were originally defined by their preference for MUSCARINE over NICOTINE. There are several subtypes (usually M1, M2, M3....) that are characterized by their cellular actions, pharmacology, and molecular biology.

Inhibitory innervation of cat sphincter of Oddi. (1/15397)

1 Electrical stimulation with trains of 0.1-0.2 ms pulses of the cat isolated sphincter of Oddi inhibited the spontaneous contractile activity and lowered base-line tension considerably. A contraction usually followed the period of stimulation. 2 These inhibitory effects were prevented by tetrodotoxin 0.1-0.5 mug/ml but were not reduced by hexamethonilm, morphine, or blockade of alpha- or beta-adrenoreceptors of cholinoceptors with phenoxy-benzamine propranolol or atropine, respectively. 3 Adenosine-5'-triphosphate (ATP) and adenosine-5'-diphosphate (ADP) inhibited the spontaneous sphincter activity and caused relaxation thus mimicking the effects of the C-terminal octapeptide of cholecystokinin (C8-CCK), isoprenaline and prostaglandin E1 and E2. 4 ATP alone (greater than 100 mug/ml) or ATP (greater than 10 mug/ml) plus dipyridamole (1 mug/ml), relaxed the sphincter to the same degrees as did the field stimulation. 5 In sphincter maximally contracted by acetylcholine, the effect of stimulation was more marked than that recorded in uncontracted preparations. 6 The present findings suggest that the sphincter of Oddi receives inhibitory nerves that are neither cholinergic nor adrenergic.  (+info)

Single blind, randomised controlled trial of pelvic floor exercises, electrical stimulation, vaginal cones, and no treatment in management of genuine stress incontinence in women. (2/15397)

OBJECTIVE: To compare the effect of pelvic floor exercises, electrical stimulation, vaginal cones, and no treatment for genuine stress incontinence. DESIGN: Stratified, single blind, randomised controlled trial. SETTING: Multicentre. PARTICIPANTS: 107 women with clinically and urodynamically proved genuine stress incontinence. Mean (range) age was 49.5 (24-70) years, and mean (range) duration of symptoms 10.8 (1-45) years. INTERVENTIONS: Pelvic floor exercise (n=25) comprised 8-12 contractions 3 times a day and exercise in groups with skilled physical therapists once a week. The electrical stimulation group (n=25) used vaginal intermittent stimulation with the MS 106 Twin at 50 Hz 30 minutes a day. The vaginal cones group (n=27) used cones for 20 minutes a day. The untreated control group (n=30) was offered the use of a continence guard. Muscle strength was measured by vaginal squeeze pressure once a month. MAIN OUTCOME MEASURES: Pad test with standardised bladder volume, and self report of severity. RESULTS: Improvement in muscle strength was significantly greater (P=0.03) after pelvic floor exercises (11.0 cm H2O (95% confidence interval 7.7 to 14.3) before v 19.2 cm H2O (15.3 to 23.1) after) than either electrical stimulation (14.8 cm H2O (10. 9 to 18.7) v 18.6 cm H2O (13.3 to 23.9)) or vaginal cones (11.8 cm H2O (8.5 to 15.1) v 15.4 cm H2O (11.1 to 19.7)). Reduction in leakage on pad test was greater in the exercise group (-30.2 g; -43. 3 to 16.9) than in the electrical stimulation group (-7.4 g; -20.9 to 6.1) and the vaginal cones group (-14.7 g; -27.6 to -1.8). On completion of the trial one participant in the control group, 14 in the pelvic floor exercise group, three in the electrical stimulation group, and two in the vaginal cones group no longer considered themselves as having a problem. CONCLUSION: Training of the pelvic floor muscles is superior to electrical stimulation and vaginal cones in the treatment of genuine stress incontinence.  (+info)

Cerebellar Purkinje cell simple spike discharge encodes movement velocity in primates during visuomotor arm tracking. (3/15397)

Pathophysiological, lesion, and electrophysiological studies suggest that the cerebellar cortex is important for controlling the direction and speed of movement. The relationship of cerebellar Purkinje cell discharge to the control of arm movement parameters, however, remains unclear. The goal of this study was to examine how movement direction and speed and their interaction-velocity-modulate Purkinje cell simple spike discharge in an arm movement task in which direction and speed were independently controlled. The simple spike discharge of 154 Purkinje cells was recorded in two monkeys during the performance of two visuomotor tasks that required the animals to track targets that moved in one of eight directions and at one of four speeds. Single-parameter regression analyses revealed that a large proportion of cells had discharge modulation related to movement direction and speed. Most cells with significant directional tuning, however, were modulated at one speed, and most cells with speed-related discharge were modulated along one direction; this suggested that the patterns of simple spike discharge were not adequately described by single-parameter models. Therefore, a regression surface was fitted to the data, which showed that the discharge could be tuned to specific direction-speed combinations (preferred velocities). The overall variability in simple spike discharge was well described by the surface model, and the velocities corresponding to maximal and minimal discharge rates were distributed uniformly throughout the workspace. Simple spike discharge therefore appears to integrate information about both the direction and speed of arm movements, thereby encoding movement velocity.  (+info)

Spinal cord-evoked potentials and muscle responses evoked by transcranial magnetic stimulation in 10 awake human subjects. (4/15397)

Transcranial magnetic stimulation (TCMS) causes leg muscle contractions, but the neural structures in the brain that are activated by TCMS and their relationship to these leg muscle responses are not clearly understood. To elucidate this, we concomitantly recorded leg muscle responses and thoracic spinal cord-evoked potentials (SCEPs) after TCMS for the first time in 10 awake, neurologically intact human subjects. In this report we provide evidence of direct and indirect activation of corticospinal neurons after TCMS. In three subjects, SCEP threshold (T) stimulus intensities recruited both the D wave (direct activation of corticospinal neurons) and the first I wave (I1, indirect activation of corticospinal neurons). In one subject, the D, I1, and I2 waves were recruited simultaneously, and in another subject, the I1 and I2 waves were recruited simultaneously. In the remaining five subjects, only the I1 wave was recruited first. More waves were recruited as the stimulus intensity increased. The presence of D and I waves in all subjects at low stimulus intensities verified that TCMS directly and indirectly activated corticospinal neurons supplying the lower extremities. Leg muscle responses were usually contingent on the SCEP containing at least four waves (D, I1, I2, and I3).  (+info)

99mTc-labeled vasoactive intestinal peptide receptor agonist: functional studies. (5/15397)

Vasoactive intestinal peptide (VIP) is a naturally occurring 28-amino acid peptide with a wide range of biological activities. Recent reports suggest that VIP receptors are expressed on a variety of malignant tumor cells and that the receptor density is higher than for somatostatin. Our aims were to label VIP with 99mTc--a generator-produced, inexpensive radionuclide that possesses ideal characteristics for scintigraphic imaging--and to evaluate 99mTc-VIP for bioactivity and its ability to detect experimental tumors. METHODS: VIP28 was modified at the carboxy terminus by the addition of four amino acids that provided an N4 configuration for a strong chelation of 99mTc. To eliminate steric hindrance, 4-aminobutyric acid (Aba) was used as a spacer. VIP28 was labeled with 1251, which served as a control. Biological activity of the modified VIP28 agonist (TP3654) was examined in vitro using a cell-binding assay and an opossum internal anal sphincter (IAS) smooth muscle relaxivity assay. Tissue distribution studies were performed at 4 and 24 h after injection, and receptor-blocking assays were also performed in nude mice bearing human colorectal cancer LS174T. Blood clearance was examined in normal Sprague-Dawley rats. RESULTS: The yield of 99mTc-TP3654 was quantitative, and the yields of 125I-VIP and 1251-TP3654 were >90%. All in vitro data strongly suggested that the biological activity of 99mTc-TP3654 agonist was equivalent to that of VIP28. As the time after injection increased, radioactivity in all tissues decreased, except in the receptor-enriched tumor (P = 0.84) and in the lungs (P = 0.78). The tumor uptake (0.23 percentage injected dose per gram of tissue [%ID/g]) was several-fold higher than 125I-VIP (0.06 %ID/g) at 24 h after injection in the similar system. In mice treated with unlabeled VIP or TP3654, the uptake of 99mTc-TP3654 decreased in all VIP receptor-rich tissues except the kidneys. The blood clearance was biphasic; the alpha half-time was 5 min and the beta half-time was approximately 120 min. CONCLUSION: VIP28 was modified and successfully labeled with 99mTc. The results of all in vitro examinations indicated that the biological activity of TP3654 was equivalent to that of native VIP28 and tumor binding was receptor specific.  (+info)

Uterine peristalsis during the follicular phase of the menstrual cycle: effects of oestrogen, antioestrogen and oxytocin. (6/15397)

Uterine peristalsis, directing sustained and rapid sperm transport from the external cervical os or the cervical crypts to the isthmic part of the tube ipsilateral to the dominant follicle, changes in direction and frequency during the menstrual cycle, with lowest activity during menstruation and highest activity at mid cycle. It was therefore suggested that uterine peristalsis is under the control of the dominant follicle with the additional involvement of oxytocin. To test this hypothesis, vaginal sonography of uterine peristalsis was performed in the early, mid and late proliferative phases, respectively, of cycles of women treated with oestradiol valerate and with human menopausal gonadotrophin following pituitary downregulation, with clomiphene citrate and with intravenous oxytocin, respectively. Administration of oestradiol valerate resulted in oestradiol serum concentrations comparable with the normal cycle with a simulation of the normal frequency of peristaltic contractions. Elevated oestradiol concentrations and bolus injections of oxytocin resulted in a significant increase in the frequency of peristaltic contractions in the early and mid follicular phases, respectively. Chlomiphene tended, though insignificantly so, to suppress the frequency of peristaltic waves in the presence of elevated oestradiol concentrations. In the late follicular phase of the cycle extremely elevated oestradiol concentrations as well as the injection of oxytocin resulted only in an insignificant further increase of peristaltic frequency. In the normal cycles, as well as during extremely elevated oestradiol concentrations and following oxytocin administration, the peristaltic contractions were always confined to the subendometrial layer of the muscular wall. The results and the review of literature indicate that uterine peristalsis during the follicular phase of the menstrual cycle is controlled by oestradiol released from the dominant follicle with the probable involvement of oxytocin, which is presumably stimulated together with its receptor within the endometrial-subendometrial unit and therefore acting in an autocrine/paracrine fashion. Since unphysiological stimulation with oestradiol and oxytocin did not significantly increase the frequency of uterine peristalsis in the late follicular phase of the cycle it is assumed that normal preovulatory frequency of uterine peristalsis is at a level which cannot be significantly surpassed due to phenomena of refractoriness of the system.  (+info)

Adrenoreceptors of the guinea-pig urinary bladder. (7/15397)

1 Adrenaline, noradrenaline and isoprenaline (5 mug/ml) did not affect the resting tone of the isolated urinary bladder of the guinea-pig. 2 The catecholamines (1-2 mug/ml) inhibited neuronally evoked contractions at various stimulation frequencies; the inhibition was maximum at 2 Hz and minimum at 50 Hz. Isoprenaline produced maximum inhibition. 3 Propranolol (0.5 mug/ml) completely blocked the catecholamine-induced inhibition at all the frequencies employed. The concentration-response curves of isoprenaline at 2, 10 and 50 Hz were characteristically shifted by propranolol (50 ng/ml). Phenoxybenzamine (0.2 mug/ml) was totally ineffective. 4 In some experiments adrenaline significantly raised the tone of the bladder exposed to propranolol; this effect could be blocked by phenoxybenzamine. 5 Acetylcholine-induced bladder contractions were inhibited by adrenaline (2 mug/ml); the inhibition was completely blocked by propranolol (0.5 mug/ml). 6 The results indicate the presence of an inhibitory beta-adrenoceptor and suggest the possibility of an excitatory alpha-adrenoceptor in guinea-pig urinary bladder.  (+info)

The cat lung strip as an in vitro preparation of peripheral airways: a comparison of beta-adrenoceptor agonists, autacoids and anaphylactic challenge on the lung strip and trachea. (8/15397)

1 A new in vitro preparation, the isolated lung strip of the cat, is described for investigating the direct effect of drugs on the smooth muscle of the peripheral airways of the lung. The preparation comprises a thin strip of lung parenchyma which can be mounted in a conventional organ bath for isometric tension recording. Its pharmacological responses have been characterized and compared with the isolated tracheal preparation of the cat. 2 The lung strip exhibited an intrinsic tone which was relaxed by catecholamines, aminophylline and flufenamate. It was contracted strongly by histamine, prostaglandin F2alpha, acetylcholine, compound 48/80, potassium depolarizing solution and alternating current field stimulation. In contrast, the cat trachea was unresponsive to histamine and prostaglandin F2alpha and did not exhibit an intrinsic tone. 3 (-)-Isoprenaline and (-)-adrenaline were much more potent in relaxing the lung strip than the trachea. The potency order of relaxation responses to isoprenaline, adrenaline and (+/-)-noradrenaline in the lung strip was isoprenaline greater than adrenaline greater than noradrenaline but in the trachea was isoprenaline greater than noradrenaline greater than or equal to adrenaline. 4 beta2-Adrenoceptor selective agonists salbutamol and terbutaline were more potent in the lung strip than the trachea, suggesting beta2-adrenoceptors predominated in the lung strip. Propranolol was equipotent in inhibiting isoprenaline relexations of the lung strip and trachea, whereas practolol was much less effective in inhibiting lung strip than trachea, further supporting a predominance of beta2-adrenoceptors in lung strip and beta1-adrenoceptors in trachea. 5 Strong Schultz-Dale type contractions were elicited in both lung strips and trachea by Ascaris lumbricoides antigen in actively sensitized cats. The initial phase of the contractile response of the lung strip following challenge was shown to be due to histamine release and was absent in the trachea. The delayed phase of the contraction which took several minutes to develop in both the mepyramine-treated lung strip and trachea was not due to prostaglandins E1, F2alpha or bradykinin, the probable mediator being slow reacting substance of anaphylaxis (SRS-A). 6 It is concluded that the isolated lung strip of the cat is useful as an in vitro model for investigating the effect of drugs on the smooth muscle of the peripheral airways of the lungs.  (+info)

TY - JOUR. T1 - Brain functional connectivity is different during voluntary concentric and eccentric muscle contraction. AU - Yao, Wan X.. AU - Jiang, Zhiguo. AU - Li, Jinqi. AU - Jiang, Changhao. AU - Franlin, Crystal G.. AU - Lancaster, Jack L. AU - Huang, Yufei. AU - Yue, Guang H.. PY - 2016/11/15. Y1 - 2016/11/15. N2 - Previous studies report greater activation in the cortical motor network in controlling eccentric contraction (EC) than concentric contraction (CC) of human skeletal muscles despite lower activation level of the muscle associated with EC. It is unknown, however, whether the strength of functional coupling between the primary motor cortex (M1) and other involved areas in the brain differs as voluntary movements are controlled by a network of regions in the primary, secondary and association cortices. Examining fMRI-based functional connectivity (FC) offers an opportunity to measure strength of such coupling. To address the question, we examined functional MRI (fMRI) data ...
Breakdown of microtubules takes place at the tips of tubules at the distal ends of axopodia when axopodial shortening is induced with colchicine. When small flagellates are captured for ingestion, rapid contraction of axopodia (100 μm in under a second) occurs which apparently involves breakdown of axonemal microtubules. Elongation of a single axopodium after rapid contraction, when all other axopodia are of normal length, proceeds at the same rate as it does when all the axopodia are growing out after microtubule-breakdown induced by cold treatment. In both cases the rate of elongation decreases as axopodia increase in length. Axopodia elastically resist mild bending along their longitudinal axes. They yield nonelastically when more severe bending is applied; bends are formed at certain points along their longitudinal axes. These bends move out along axopodia to their tips.. ...
During an eccentric contraction, the muscle elongates while under tension due to an opposing force being greater than the force generated by the muscle.[1] Rather than working to pull a joint in the direction of the muscle contraction, the muscle acts to decelerate the joint at the end of a movement or otherwise control the repositioning of a load. This can occur involuntarily (when attempting to move a weight too heavy for the muscle to lift) or voluntarily (when the muscle is smoothing out a movement). Over the short-term, strength training involving both eccentric and concentric contractions appear to increase muscular strength more than training with concentric contractions alone.[2] During an eccentric contraction of the biceps muscle, the elbow starts the movement while bent and then straightens as the hand moves away from the shoulder. During an eccentric contraction of the triceps muscle, the elbow starts the movement straight and then bends as the hand moves towards the shoulder. ...
The foundations for this topic can be found in the previous 4 articles in the series. Building off the understanding of viscoelastic tissues that are sensitive to the rate at which force is applied, we will examine training strategies designed to maximize muscle stimulation while avoiding injury. There are 3 types of muscle contraction:. Concentric - the muscle is shortening while contracting (the positive rep). Isometric - the muscle does not change length while contracting. Eccentric - the muscle is lengthening while contracting (the negative rep). It is widely misstated, and then repeated by others, that eccentric contractions produce more force than isometric contractions which produce more force than concentric contractions. This is not true. The force generated by muscle contraction is determined by the equation for torque reviewed in the last article, independent of the shortening or lengthening during contraction (minus a subtle detail - hysteresis - which is beyond the scope of our ...
Definition of concentric contraction in the Financial Dictionary - by Free online English dictionary and encyclopedia. What is concentric contraction? Meaning of concentric contraction as a finance term. What does concentric contraction mean in finance?
Static muscular contraction in anesthetized animals has been firmly established to reflexly increase arterial pressure. Although group III and IV muscle afferents are known to be responsible for this reflex pressor response, there is no evidence that the stimulation of muscle mechanoreceptors, many of which are supplied by group III fibers, plays a role in causing this contraction-induced reflex effect. To provide this evidence, we recorded renal sympathetic nerve activity in chloralose-anesthetized cats while contracting the triceps surae muscles. We found that static contraction tripled renal nerve activity within three seconds of its onset, an increase that was abolished by cutting the L6 and S2 dorsal roots. On average, the contraction-induced increase in renal nerve activity was observed 0.8 +/- 0.1 seconds after the onset of this maneuver. In addition, intermittent tetanic contractions synchronized renal nerve discharge so that a burst of activity was evoked by each contraction. A ...
Definition of eccentric contraction in the Financial Dictionary - by Free online English dictionary and encyclopedia. What is eccentric contraction? Meaning of eccentric contraction as a finance term. What does eccentric contraction mean in finance?
Eccentric exercise or resistance training is currently being used as a form of rehabilitation for sport injuries, but also as an alternative form of exercise for the elderly, those affected by neurological disorders, COPD, cardiopulmonary disorders, and cancer.[6] Muscle loss is a big problem faced by the people afflicted with the above disorders and many cannot participate in rigorous exercise protocols. Eccentric muscle contractions produce high forces with low-energy cost. According to Hortobágyi due to these properties eccentric exercise has the greatest potential for muscle strengthening.[7] To strengthen muscle the external force must exceed the muscle while it lengthens.[8] The definition of eccentric contraction is almost the exact definition of muscle strengthening. Perceived muscle damage: There is a stipulation regarding eccentric contractions in that they actually cause muscle damage and injury. Eccentric contraction may result in delayed onset muscle soreness however; the ...
The main new findings from this study of afferent arterioles from normal C57BL/6 mice were that increasing the PP from 40 to 80 mm Hg caused a myogenic contraction accompanied by an increase in ROS signal whether detected by dihydroethidium or tempo-9AC. The fluorescent ROS signal was predominately O2 · −, because it was reduced by incubation with PEG-SOD or Tempol but not with PEG-CAT and was upstream from Ca2+ because it persisted in Ca2+-free medium. Incubation of vessels with Tempol, PEG-SOD, apocynin, or DPI reduced basal and myogenic tone, whereas PEG-CAT was not effective, indicating that the responses were enhanced by O2 · − generated from NADPH oxidase. The moderation of myogenic contractions by Tempol was prevented by preincubation with PEG-SOD but was preserved by preincubation with PEG-CAT. H2O2 caused contractions at concentrations ,50 μmol/L but inhibited myogenic responses at 25 μmol/L. l- NAME increased basal tone but did not affect pressure-induced ROS generation. ...
Looking for Isotonic Muscle Contraction? Find out information about Isotonic Muscle Contraction. contraction of a muscle at unchanging tension, expressed in a decrease in its length and an increase in its transverse section. Purely isotonic muscle... Explanation of Isotonic Muscle Contraction
Isotonic Vs. Isometric Contraction. Every exercise you do involves some sort of muscle contraction. Exercises with movement involve isotonic muscle contractions and exercises without movement involve isometric muscular contractions. Knowing the difference between these two different types of contractions can help you ...
It is intriguing how the mechanics of molecular motors is regulated to perform the mechanical work in living systems. In sharp contrast to the conventional wisdom, recent experiments indicated that motor force maintains ∼6 pN upon a wide range of filament loads during skeletal muscle contraction at the steady state. Here we find that this rather precise regulation which takes place in an essentially chaotic system, can be due to that a working motor is arrested in a transitional state when the motor force is ∼6 pN. Our analysis suggests that the motor force can be self-regulated through chemomechanical coupling, and motor force homeostasis is a built-in feature at the level of a single motor, which provides insights to understanding the coordinated function of multiple molecular motors existing in various physiological processes. With a coupled stochastic-elastic numerical framework, the kinetic model for a Actin-myosin-ATP cycle constructed in this work might pave the way to decently ...
The muscles can perform the same function in a specific segment (muscles of fast and slow contraction), and at the same time be antagonistic in relation to muscular action (flexors or extensors). The present research aimed to study the morphology, frequency and metabolism of fiber types and the contractile characteristics of extensor and flexors muscles of rabbit. We studied muscles anterior tibialis (AT), flexor digitorum supeficialis (FDS), extensor digitorum longus (EDL) and posterior tibialis (PT). The muscles were submitted to the techniques HE, NADH-TR and myofibrillar ATPase. In EDL and PT extensor muscles, the frequencies of red (SO + FOG) and white fibers (FG) were 68.77% and 31.23% versus 58.87% and 41.13%, respectively. In the AT and FDS flexor muscles, these frequencies were 75.14% and 24.86% versus 73.89% and 26.11%, respectively. In extensor muscles, the percentage of slow contraction fibers was 8.05% in EDL and 9.74% in PT, and in fast contraction, 91.95% in EDL and 90.26% in PT. ...
When a muscle contraction is required, it receives a message from the brain for voluntary contractions and from the spinal cord for reflex contractions. This message, called a nerve impulse or action potential, is carried along motoneurons to the muscle. It would not be practical for all the fibers in a given muscle to contract every time the motoneuron discharged an action potential. Therefore, before the motoneuron reaches the target muscle, it divides into many separate branches that independently activate groups of muscle fibers. These groupings are referred to as motor units. The number of fibers per motor unit depends on the specific muscle. A small muscle used for intricate movements will have less than 100 fibers per motor unit and less than 100 motor units in total. A large muscle used for weight-bearing and propulsion will have several thousand fibers per motor unit and several hundred motor units ...
Weight training is all about throwing the weights about right? Even the best bodybuilder of all time in my opinion, Arnie, named his video Pumping Iron which says a lot. Yet I find myself tearing my hair out when I watch most people in the gym lift weights, to be blunt their form is pretty poor. To be more specific, I am referring to their repetition tempo during each phase of the muscle contraction. Today I wanted to educate you a little on muscle contractions and the importance of utilising them.ConcentricConcentric muscle contractions occur when the muscle shortens, so a doing a bicep curl is a perfect example. Many people will perform this part of the repetition with very little control of the weight and instead employ a great deal of momentum to shift the resistance from A to B. This is a great way to go if building a super-sized ego is the main goal, but if building quality lean muscle tissue is something you are interested in I suggest you listen.During a concentric muscle contraction by
Before I start talking about using different contraction types in training and the benefits they will have, first I must explain to anyone who doesnt know about the 3 different types of contraction. Keeping it nice and basic, there are 3 different ways that your muscle can contract in order to move a part of your body. Concentric - a concentric contraction is where the muscle shortens in length causing your bodypart to move. For example when you concentrically contract your bicep, it shortens and your arm bends (flexes). Most people who will train will be primarily focused on this type of contraction as it is the one that moves the weight against the resistance. For example it is the concentric contraction that pushes the bar off your chest to lockout on a bench press. Eccentric - an eccentric contraction is the lengthening of the muscle. This occurs when you lower the weight under control. Its the opposite movement to the concentric contraction but it isnt the antagonistic muscle that
During a stretch- shortening cycle (SSC), muscle force attained during concentric contractions (shortening phase) is potentiated by the preceding eccentric contractions (lengthening phase). The purpose of this study was to examine the influence of joint angular velocity on force potentiation induced by SSC (SSC effect). Twelve healthy men (age, 24.2 ± 3.2 years; height, 1.73 ± 0.05 m; body mass, 68.1 ± 11.0 kg) participated in this study. Ankle joint angle was passively moved by a dynamometer, with range of motion from dorsiflexion (DF) 15° to plantarflexion (PF) 15°. Muscle contractions were evoked by tetanic electrical stimulation. Joint angular velocity of concentric contraction was set at 30°/s and 150°/s. Magnitude of SSC effect was calculated as the ratio of joint torque obtained by concentric contraction with preliminary eccentric contraction trial relative to that obtained by concentric contraction without preliminary eccentric contraction trial. As a result, magnitude of SSC effect
Below are two different but similar descriptions of muscle contraction that explain the processes involved in notification, contraction, and relaxation.. The following steps are involved in muscle contraction:. (1) The sequence of events leading to contraction is initiated somewhere in the central nervous system, either as voluntary activity from the brain or as reflex activity from the spinal cord.. (2) A motor neuron in the ventral horn of the spinal cord is activated, and an action potential passes outward in a ventral root of the spinal cord.. (3) The axon branches to supply a number of muscle fibers called a motor unit, and the action potential is conveyed to a motor end plate on each muscle fiber.. (4) At the motor end plate, the action potential causes the release of packets or quanta of acetylcholine into the synaptic clefts on the surface of the muscle fiber.. (5) Acetylcholine causes the electrical resting potential under the motor end plate to change, and this then initiates an action ...
Ever wonder how a muscle contracts to create movement? Weve come up with a simple guide to help you understand muscle contraction.
1. The effect of pH on excitation-contraction coupling in skeletal muscle of the toad was examined using a skinned fibre preparation which gives ready access to the intracellular environment while still allowing stimulation of Ca2+ release by the normal voltage-sensor mechanism. 2. In each fibre, depolarization-induced responses (produced by changing the ions in the bathing solution) were examined first at pH 7.1, and then at another pH between 6.1 and 8.0. At all pH levels examined, the first depolarization elicited a large response which was slightly greater (pH 7.6 and 8.0) or smaller (pH 6.6 and 6.1) than that at pH 7.1. The size of the first depolarization-induced response varied with pH in almost exactly the same manner as did the maximum Ca(2+)-activated response. The duration of the depolarization-induced response at all other pH levels was longer than at pH 7.1. 3. Repeated depolarizations (30 s or more apart) produced similar responses at pH 7.1, but at all other pH levels examined the ...
I do not know what natural contractions feel like however contractions brought on by pitocin are the precise absolute plain satan. At 38 weeks I woke to them happening every 10 minutes - tho they eased after I moved & they had been brief & not painful, so I didnt fear an excessive amount of.. Apply labor contractions are in any other case known as Braxton Hicks contractions and are widespread from week 32 until birth. Nonetheless, in the event youre writing a tutorial paper or the rest thats formal, you could want to keep away from contractions. The time between contractions includes the length or length of the contraction and the minutes in between the contractions (called the interval).. Should you go to the hospital only to search out out that youre having false labor, dont feel unhealthy about it. It is sometimes laborious to know the difference between actual and false labor. One of the reasons it is troublesome to answer the question what do contractions feel like is because the ...
I have to do a literature review on a topic involving neurophysiology. So I chose to pick one about the force-velocity relationship of muscle contractions. The relationship shows that as muscle velocity increases, muscle force decreases. I was wondering if anybody has any research articles that show the opposite: That as velocity increases muscle force increases as well. I have searched to no avail. I appreciate any help.
Types of Contraction. All types of strength are a result of individual muscle fibres contracting, a muscle fibre contracts fully or not at all, the number of muscle fibres that contract simultaneously define the amount of force a muscle can produce and whether that muscle can overcome, maintain, or slowly lower the load its working against.. If the force generated by the muscle fibres is greater than the load, then the entire muscle length will shorten and the load will move, this is called a Concentric Contraction.. When the load is greater than the force produced by the muscle fibres the muscle will lengthen, this is called an Eccentric Contraction, even though the muscle as a whole is lengthening, individual fibres are still contracting trying to resist the load.. Concentric/Eccentric contractions are collectively known as Dynamic contractions. When the force exerted by the fibres is equal to the load no movement takes place, this is called an Isometric Contraction. This of special interest ...
Trusculpt flex involves direct stimulation of muscles through the electrodes located in the handpiece, resulting in full muscle contractions similar to voluntary contractions during physical exercise. The contractions induced by truSculpt flex are more intense than physical exercise and such rapid contractions result in increased muscle mass, strength, and tone. One of the limitations of electrical muscle stimulation in increasing muscle strength is that the same muscles that are superficially located are recruited during repetitive use3. This can lead to muscle fatigue and damage. truSculpt flex overcomes this limitation by using multi-directional stimulation with 3 treatment modes, involving different current intensities. Increasing current intensity through the course of a training session allows for the recruitment of deeper muscle groups during training and thus avoids muscle damage4. Altering the direction of the current can also avoid stimulation of the same muscles and facilitate ...
Several studies reported that exercising one limb produces gains in motor output in the same muscle of the un-exercised, contralateral limb. This phenomenon is called cross education. There are also data to suggest that muscle and brain activation are different when muscles shorten and lengthen and that the amount of cross education may be also different according to the type of muscle contraction. This thesis is an initial effort in the form of a cross sectional study to shed light on the mechanism of cross education. This project examines the hypothesis that spinal excitability varies in the resting limb according to the type and intensity of muscle contraction in the contralateral limb. The purpose of this study was to compare spinal excitability in the right wrist flexors during and after concentric and eccentric contraction of the left wrist flexors at an intensity of 100% and 60% of the maximum. Ten healthy right-handed subjects (5 females, 5 males, mean age 21 [plus/minus] 3 years) ...
Researchers in the Department of Human Health and Nutritional Sciences have gained new insights into the fundamental properties that govern muscle activity and influence our day-to-day movement.. Prof. Geoffrey Power and his research group have discovered a unique interplay between our nervous system and a phenomenon that occurs during muscle contraction known as torque depression.. Muscle contraction is what drives human movement. For example, the movement associated with taking a drink involves contraction and shortening of the bicep muscles. This contraction generates a force called torque that causes the forearm to rotate at the elbow towards your mouth, and allows you to enjoy your morning coffee. But not all muscle contractions are created equal. During contractions where the muscle does not shorten, such as holding a travel mug at waist-level between sips, the muscle generates more torque compared to a muscle that had to shorten to match the same position. The lower amount of torque ...
A new wearable microscope enables in vivo monitoring of individual muscle fiber contractions in live humans, a feat that has not been possible despite our longstanding physiological understanding of how muscles contract. According to the report in the December 16 Neuron online, researchers led by senior authors Scott Delp and Mark Schnitzer at Stanford University in Palo Alto, California, have developed a microscope by connecting an infrared light source to a fine needle containing miniaturized optics that is inserted into the muscle. The device can distinguish fast and slow twitch muscles, stimulate muscle contractions, and track changes in properties of the individual contractile units of skeletal muscles, or sarcomeres, that occur due to injury or disease. This compact, portable device could fit on a bedside pushcart, and the researchers hope to ultimately develop it into a clinically useful device for diagnosing neuromuscular diseases and monitoring their progression in human ...
Dear Readers, Audrey is 56 years old and has been experiencing increasing episodes of muscle contractions in her calves and even in her feet at times. The contractions can last from a few seconds to more than 15 minutes. They occur mainly...
THE CONTRACTION AND Relaxation OF CARDIAC FIBERS Through contraction of your coronary heart muscle fiber inside the ventricles, blood enters the arteries that depart the center for the other organs of the physique. After the contraction, the ventricles then take it easy to reduced force and make place for blood from atria. The decreased tension is definitely the diastolic stress from peace when the systolic strain occurs with the contraction of your hearts ventricular muscular tissues.. The center muscle fibers are interconnected and glimpse more such as skeletal muscle. The muscle fiber has both of those the skinny and thick filaments having a tiny sarcoplasmic reticulum. The calcium ions originate from inside and outdoors the cells thus earning the contraction of your cardiac muscle mass fiber actin-regulated . The thin and thick filaments slide using an enhance in calcium ions brought on via the motion potential within the membrane a result of the activation of ATPase with the myosin. Bulk ...
Purpose: To determine the effects of concentric and eccentric muscle contractions on IL-6 signaling and its possible downstream regulation of HSP-72 expression in human skeletal muscle, and whether contraction-induced ...
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The OF studied show marked differences in contractile activity. Whilst CF contract matrix by 55% within the first 24h, the same number of TF only contract it by 10%. Whilst contraction by CF quickly reaches a plateau, TF generate sustained contraction. Final matrix contraction is the same. SF only contract matrix at higher cell density. CF generate the greatest force; TF generate 2/3 less, and SF hardly any. Three main factors determine contraction efficiency: cell volume (CF,TF,SF), cell protrusive and retractile activity (dynamic index, DI), and efficient binding to matrix fibrils. DI mirrors force generation. ML9 reduces DI and force generation. Ilomastat has a modest effect on DI and force, but dramatically inhibit matrix contraction, indicating that additional mechanisms are involved. ...
In a previous communication by one of us (G. B. (1)) it was shown that graded contractions and relaxations of natural form can be obtained in the diaphragm and in skeletal nerve muscle preparation by manipulating a faradic induction apparatus in a special manner. Briefly, this manipulation consists in imparting a smooth to-and-fro movement to the secondary coil of the apparatus, the movement taking place between the points of just maximal and just minimal stimulation. These to-and-fro movements cause certain changes of amplitude in the stimulating current, and the various patterns thus produced are faithfully repeated in the contractions of the experimental muscle, provided the changes are kept within the above-mentioned limiting points. An attempt has been made in the present research to obtain reciprocal contraction of antagonistic muscles by an extension of the above method. In the working-out of the new method of excitation, and in its application to double nerve-muscle preparations, the ...
Delayed-onset muscle soreness (DOMS) describes an entity of ultrastructural muscle damage. The manifestation of DOMS is caused by eccentric muscle contractions or unaccustomed forms of exercise. Clinical signs include impaired muscular force capacities, painful restriction of movement, stiffness, sw …
Approach and Results-Real-time polymerase chain reaction, immunohistochemistry, and Western analyses supported the synthesis and expression of chemerin in perivascular adipose tissue, whereas the primary chemerin receptor ChemR23 was expressed both in the tunica media and endothelial layer. The ChemR23 agonist chemerin-9 caused receptor, concentration-dependent contraction in the isolated rat thoracic aorta, superior mesenteric artery, and mesenteric resistance artery, and contraction was significantly amplified (more than 100%) when nitric oxide synthase was inhibited and the endothelial cell mechanically removed or tone was placed on the arteries. The novel ChemR23 antagonist CCX832 inhibited phenylephrine-induced and prostaglandin F2α-induced contraction (+perivascular adipose tissue), suggesting that endogenous chemerin contributes to contraction. Arteries from animals with dysfunctional endothelium (obese or hypertensive) demonstrated a pronounced contraction to chemerin-9. Finally, ...
DALLAS - Researchers at UT Southwestern Medical Center have identified a previously unrecognized small protein in cells of the human heart that plays a key role in heart muscle contraction. The protein is made from an RNA that was previously believed to be a blank or non-coding RNA, suggesting there may be many other small non-coding segments that play important biological roles. Significantly, the findings published today in Science offer a potential new target for developing therapeutics to boost the strength of cardiac muscle contractions in patients with heart failure, a chronic condition in which the heart pumps too weakly to supply adequate oxygen to the body. The new protein, which the researchers have named dwarf open reading frame (DWORF), comprises just 34 amino acids, making it the third smallest protein known to be encoded in the mouse genome. By comparison, an average-sized protein is 10 times larger, including about 350 amino acids. DWORF is also encoded in the human genome. The ...
You searched for: Creator Karreman, George Remove constraint Creator: Karreman, George Subject Muscle Contraction Remove constraint Subject: Muscle Contraction ...
where Λ is the ratio of muscle length to the optimal length at which maximal isometric tension is produced, and α(Λ) is a function numerically equal to the ratio of the tetanic isometric force to its maximum value. The single dimensionless constant in this relation, B, can be calculated from model parameters characterizing muscle dynamics at the optimum length, and has a value near unity for frog sartorius at 0°C. The predicted behavior is shown to agree reasonably well with experimental measurements of heat production and phosphocreatine (PCr) hydrolysis. The model relates the isometric energy rates to PCr hydrolysis in (1) cross-bridge interactions, and (2) calcium pumping into the sarcoplasmic reticulum.. ...
TY - JOUR. T1 - Muscle activation is enhanced with multi- and uni-articular bilateral versus unilateral contractions. AU - Behm, D.G.. AU - Power, K.E.. AU - Drinkwater, Eric. N1 - Imported on 12 Apr 2017 - DigiTool details were: Journal title (773t) = Applied Physiology, Nutrition and Metabolism. ISSNs: 1066-7814; PY - 2003. Y1 - 2003. N2 - Ten resistance trained (RT) and 6 non-resistance trained (NRT) subjects were used to determine differences in quadriceps activation between isometric single and double knee extensions and squat contractions. Greater inactivation, as measured by the interpolated twitch technique, was recorded with single (RT: 16.5%, NRT: 17.6%) than double leg extensions (RT: 8.4%, NRT: 13.4%) or squats (RT: 4.03%, NRT: 1.7%). There was no significant difference between the maximum voluntary contraction (MVC) force of the dominant leg during single and double leg extensions. However, in NRT subjects, the contralateral or non-dominant leg during double leg extensions exhibited ...
There are a number of factors that increase the risk of a quadriceps strain. For example, high forces across the muscle-tendon units combined with eccentric contraction can lead to strain injury. Excessive passive stretching or activation of a maximally stretched muscle can also cause strains. Muscle fatigue has also been shown to play a role in acute muscle injury(3). This may account for the observation of increased injury risk during the pre-season (when fitness levels tend to be lower, leading to the earlier onset of fatigue). However, of the four bellies, the RF is most frequently strained(4-8). There are a number of factors behind the increased vulnerability of RF; as well as crossing two joints, it contains a high percentage of explosive type-II fibres and also has a complex musculotendinous architecture, all of which are known to increase injury risk(9,10).. As noted in the NCAA study above, indirect trauma occurs for the most part as a result of eccentric contractions(4,11). This can ...
Although the contraction of each muscle cell is all-or non, it is obvious that body movements are not. Sometimes they are forceful, other times slight. This is easily accounted for by realizing that body movements are brought about by whole muscles (groups of muscle cells), not by single cell acting alone. Increasing the force of movement may simply be a matter of recruiting more and more cells into cooperative action. However, there are also more subtle means for changing the performance of individual cells.. The strength or, more precisely, the force a muscle is capable of exerting depends on its length. For each muscle cell, there is an optimum length or range of lengths where the contractile force is strongest. This is easily explained by the sliding fillament theory. The strength of contraction depends on the number of cross bridges that can make contact with actin fillaments. When the muscle is too long, few cross bridges can make contact, and contraction is weak. When the muscle is too ...
Instance of an apostrophe-less contraction is none, which is the contracted type of not one. Others experience cramps, contractions and discomfort for weeks before delivery. The terbutaline did settle down the contractions fairly a bit and there have been only two trips to the hospital with preterm labor scares. I had a number of demanding situations come up and certainly one of them put me into preterm labor where the contractions started to vary the cervix.. Anytime you feel contractions earlier than 37 weeks it is best to let your physician know instantly. For some, Braxton hicks contractions shall be painless, while others will find it more painful and sometimes confused with pre-labor. If you are underneath 37 weeks pregnant and you have greater than 3-4 contractions per hour, please name your doctor straight away.. What Ive observed with the irritable uterus is that if I keep lively, the contractions increase and change into more uncomfortable. Generally these contractions may be ...
Looking for eccentric, contraction muscle? Find out information about eccentric, contraction muscle. the contractile tissue that effects the movement of and within the body. Muscle tissue in the higher animals is classified as striated, smooth, or cardiac,... Explanation of eccentric, contraction muscle
DOMS is the main reason youre slow to get out of bed the next day. Theodore Hough first described this phenomenon in 1902, stating that DOMS is fundamentally the result of ruptures within the muscle.. Dont fret; its not as bad as it sounds. However, his statement still rings mostly true to this day. Research has found that eccentric muscle contractions cause tiny tears to the connective tissue and units of muscle known as myofilaments, which collectively make up a muscle fiber. It is this structural damage to the muscle that causes the pain and tenderness associated with DOMS.. Soreness usually starts around 24 hours after activity and peaks between 48 and 72 hours. From there, it usually dissipates and is gone completely 5 to 7 days after activity. The more strenuous the activity, the longer the soreness will last. Youre more likely to suffer from DOMS if you have taken a long break from exercise and are just getting started back, or, similarly, if you are engaging in physical activity ...
When you have a contraction, your womb tightens and then relaxes. For some people, contractions may feel like extreme period pains. You may have had contractions during your pregnancy, particularly towards the end. These tightenings are called Braxton Hicks contractions and are usually painless.. As labour gets going, your contractions tend to become longer, stronger and more frequent. During a contraction, the muscles tighten and the pain increases. If you put your hand on your abdomen, youll feel it getting harder; when the muscles relax, the pain fades and you will feel the hardness ease.. The contractions are pushing your baby down and opening the entrance to your womb (the cervix), ready for your baby to go through.. Your midwife will probably advise you to stay at home until your contractions become frequent. Call your midwife for guidance when your contractions are in a regular pattern and:. ...
When you have a contraction, your womb tightens and then relaxes. For some people, contractions may feel like extreme period pains. You may have had contractions during your pregnancy, particularly towards the end. These tightenings are called Braxton Hicks contractions and are usually painless.. As labour gets going, your contractions tend to become longer, stronger and more frequent. During a contraction, the muscles tighten and the pain increases. If you put your hand on your abdomen, youll feel it getting harder; when the muscles relax, the pain fades and you will feel the hardness ease.. The contractions are pushing your baby down and opening the entrance to your womb (the cervix), ready for your baby to go through.. Your midwife will probably advise you to stay at home until your contractions become frequent. Call your midwife for guidance when your contractions are in a regular pattern and:. ...
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Inactivation of excitation-contraction coupling was examined in extensor digitorum longus (EDL) and soleus muscle fibers from rats injected daily with tri-iodothyronine (T3, 150 micrograms/kg) for 10-14 d. Steady-state activation and inactivation curves for contraction were obtained from measurements of peak potassium contracture tension at different surface membrane potentials. The experiments tested the hypothesis that noninactivating tension is a window tension caused by the overlap of the activation and inactivation curves. Changes in the amplitude and voltage dependence of noninactivating tension should be predicted by the changes in the activation and inactivation curves, if noninactivating tension arises from their overlap. After T3 treatment, the area of overlap increased in EDL fibers and decreased in soleus fibers and the overlap region was shifted to more negative potentials in both muscles. Noninactivating tension also appeared at more negative membrane potentials after T3 ...
Only a few words and phrases about rhythmic contraction and comfort of cardiovascular system lean muscle in helpful coming up with Rhythmic contraction and
TY - JOUR. T1 - Twitch potentiation after voluntary contraction and neuromuscular electrical stimulation at various frequencies in human quadriceps femoris. AU - Miyamoto, Naokazu. AU - Fukutani, Atsuki. AU - Yanai, Toshimasa. AU - Kawakami, Yasuo. PY - 2012/1/1. Y1 - 2012/1/1. N2 - Introduction: In this study we aimed to compare the extent of twitch potentiation (TP) after voluntary contraction and percutaneous electrical stimulation of muscles (neuromuscular electrical stimulation: NMES) with various stimulation frequencies at equivalent target levels. Methods: Isometric knee extensions of 10 s were performed at a 40% maximal voluntary contraction level by voluntary or NMES conditioning contractions at 20, 40, and 80 H Z of the quadriceps femoris muscle. Twitch responses were elicited by stimulating the femoral nerve transcutaneously at supramaximal intensity. Results: NMES at 80 HZ induced significantly less TP (128.7 ± 17.1%) than voluntary contraction (156.2 ± 23.1%), whereas no ...
Fatigue in muscles that shorten might have other causes than fatigue during isometric contractions, since both cross-bridge cycling and energy demand are different in the two exercise modes. While isometric contractions are extensively studied, the causes of fatigue in shortening contractions are poorly mapped. Here, we investigate fatigue mechanisms during shortening contractions in slow twitch skeletal muscle in near physiological conditions. Fatigue was induced in rat soleus muscles with maintained blood supply by in situ shortening contractions at 37°C. Muscles were stimulated repeatedly (1 s on/off at 30 Hz) for 15 min against a constant load, allowing the muscle to shorten and perform work. Fatigue and subsequent recovery was examined at 20 s, 100 s and 15 min exercise. The effects of prior exercise were investigated in a second exercise bout. Fatigue developed in three distinct phases. During the first 20 s the regulatory protein Myosin Light Chain-2 (slow isoform, MLC-2s) was rapidly ...
TY - JOUR. T1 - Rapamycin administration in humans blocks the contraction-induced increase in skeletal muscle protein synthesis. AU - Drummond, Micah J.. AU - Fry, Christopher. AU - Glynn, Erin L.. AU - Dreyer, Hans C.. AU - Dhanani, Shaheen. AU - Timmerman, Kyle L.. AU - Volpi, Elena. AU - Rasmussen, Blake. PY - 2009. Y1 - 2009. N2 - Muscle protein synthesis and mTORC1 signalling are concurrently stimulated following muscle contraction in humans. In an effort to determine whether mTORC1 signalling is essential for regulating muscle protein synthesis in humans, we treated subjects with a potent mTORC1 inhibitor (rapamycin) prior to performing a series of high-intensity muscle contractions. Here we show that rapamycin treatment blocks the early (1-2 h) acute contraction-induced increase (∼40%) in human muscle protein synthesis. In addition, several downstream components of the mTORC1 signalling pathway were also blunted or blocked by rapamycin. For instance, S6K1 phosphorylation (Thr421/Ser424) ...
TY - JOUR. T1 - Dynamic imaging of skeletal muscle contraction in three orthogonal directions. AU - Lopata, R.G.P.. AU - Dijk, van, J.P.. AU - Pillen, S.. AU - Nillesen, M.M.. AU - Maas, H.. AU - Thijssen, J.M.. AU - Stegeman, D.F.. AU - Korte, de, C.L.. PY - 2010. Y1 - 2010. N2 - In this study, a multidimensional strain estimation method using biplane ultrasound is presented to assess local relative deformation (i.e., local strain) in three orthogonal directions in skeletal muscles during induced and voluntary contractions. The method was tested in the musculus biceps brachii of five healthy subjects for three different types of muscle contraction: 1) excitation of the muscle with a single electrical pulse via the musculocutaneous nerve, resulting in a so-called twitch contraction; 2) a train of five pulses at 10 Hz and 20 Hz, respectively, to obtain a submaximum tetanic contraction; and 3) voluntary contractions at 30, 60, and 100% of maximum contraction force. Results show that biplane ...
The object of this research is to compare the reflex contractions of the cruralis muscle in the decerebrate and spinal frog in response to a single break induction shock, applied to the ipsilateral sciatic nerve. Sherrington (5) studied the limb reflexes in the decerebrate and spinal cat. He showed that in the decerebrate preparation the reflex contraction of an extensor muscle was accompanied by an autogenous tonic reflex which prolonged the contraction. This autogenous tonic reflex was absent from the reflex contractions of the flexors in the decerebrate, and from the extensors in the decapitate, preparations. Sherrington (5) and Sherrington and Sowton (6) showed that in the spinal cat the reflex contraction of the tibialis anticus muscle was higher and had a more rapid ascent than in the decerebrate cat. Sherrington concluded that the mid-brain exercises an inhibitory influence over the flexor limb centres in the cord. Head (2) arrived at similar conclusions in stating that, on removal of ...
Key points Muscle glycogen (the storage form of glucose) is consumed during muscle work and the depletion of glycogen is thought to be a main contributor to muscle fatigue. In this study, we used a novel approach to first measure fatigue-induced reductions in force and tetanic Ca2+ in isolated single mouse muscle fibres following repeated contractions and subsequently quantify the subcellular distribution of glycogen in the same fibre. Using this approach, we investigated whether the decreased tetanic Ca2+ induced by repeated contractions was associated with glycogen depletion in certain subcellular regions. The results show a positive correlation between depletion of glycogen located within the myofibrils and low tetanic Ca2+ after repetitive stimulation. We conclude that subcellular glycogen depletion has a central role in the decrease in tetanic Ca2+ that occurs during repetitive contractions. In skeletal muscle fibres, glycogen has been shown to be stored at different subcellular locations: ...
Hypotheses were tested that a muscle stimulated at a frequency that elicited a maximal rate of force development (dP/dto) was fully activated during after-loaded isotonic contractions by the time the muscle developed the force necessary to displace the after-load and consequently the shortening velocity was maximum. whereas a muscle stimulated at a rate that elicited maximum tetanic force (Po) was not fully activated and under similar circumstances could not displace after-loads at maximum velocities. As controls for fully activated muscle, the same muscles were stimulated to develop Po and were then released to each after-load. Soleus muscles from 14 mice were stimulated directly in vitro at 25º C. Shortening velocities of each muscle were measured at 13 different after-loads using 4 different protocols: stimulation at a frequency that produced Po (approximately 90 Hz) with an after-loaded isotonic contraction: stimulation at 90 Hz to Po with a quick-release to each after-load; stimulation at ...
TY - JOUR. T1 - Pressor reflex response to static muscular contraction. T2 - Its afferent arm and possible neurotransmitters. AU - Kaufman, Marc. AU - Rotto, Diane M.. AU - Rybicki, Kenneth J.. PY - 1988/9/9. Y1 - 1988/9/9. N2 - Static muscular contraction has been shown to increase cardiovascular and ventilatory function in reflex manner. The sensory arm of this reflex arc is comprised of group III and IV muscle afferents. The discharge properties of these muscle afferents whose activation causes the pressor reflex response to contraction were investigated. Group III afferents were more responsive to mechanical stimuli, such as tendon stretch and probing their receptive fields than were group IV afferents. In contrast, group III afferents were less responsive to ischemic contraction than were group IV afferents. Equal percentages of group III and IV afferents were stimulated by potassium, lactic acid and arachidonic acid, each of which are metabolic products of contraction. Adenosine, phosphate ...
Most athletes stretch as part of their training regimen and it is commonly believed that this practice prevents muscle injury. We tested this belief using an animal model, in situ mouse extensor digitorum longus (EDL) muscle. One lower hindlimb was slowly stretched for 1 min on alternate days for 12 days; the other leg served as a control. The mouse was lightly anaesthetized during the stretching protocol (isofluorane). Both legs were tested in situ by measuring maximum isometric force and Show moreMost athletes stretch as part of their training regimen and it is commonly believed that this practice prevents muscle injury. We tested this belief using an animal model, in situ mouse extensor digitorum longus (EDL) muscle. One lower hindlimb was slowly stretched for 1 min on alternate days for 12 days; the other leg served as a control. The mouse was lightly anaesthetized during the stretching protocol (isofluorane). Both legs were tested in situ by measuring maximum isometric force and maximum ...
Enhanced muscle weakness is commonly experienced following stroke and may be accompanied by increased susceptibility to fatigue. To examine the contributions of central and peripheral factors to isometric muscle fatigue in stroke survivors, this study investigates changes in motor unit (MU) mean firing rate and action potential duration during, and directly following, a sustained submaximal fatiguing contraction at 30% maximum voluntary contraction (MVC). A series of short contractions of the first dorsal interosseous muscle were performed pre- and postfatigue at 20% MVC, and again following a 10-minute recovery period, by twelve chronic stroke survivors. Individual MU firing times were extracted using surface EMG decomposition and used to obtain the spike-triggered average MU action potential waveforms. During the sustained fatiguing contraction, the mean rate of change of the firing rate across all detected motor units was greater on the affected side (-0.02 ± 0.03 Hz/s) than on the less-affected
Correcting for insufficient power because of weak uterine contractions: During labour, regular palpation of the womans abdomen is done to assess strength of contractions. Insufficient contraction strength is a common reversible cause of dystocia, and acting to intervene by augmenting contraction strength with oxytocin can prevent or readily correct a state of dystocia if this is the reason for it. Very often it is the cause of dystocia. If abdominal palpation +/- tocometry suggests insufficient uterine contractions, then augmenting contractions with oxytocin may be warranted. In some cases, uterine contractions may seem strong, or there may be confounding factors making assessment of contraction strength difficult to do (ex: maternal obesity). In these cases, confirmation of weak contractions by an intrauterine pressure catheter may be useful. An intrauterine pressure catheter (IUPC) is the only accurate way of assessing the intensity (in mm Hg) of contractions, but it is more invasive and not ...
TY - JOUR. T1 - Vascular smooth muscle contraction induced by Na+ channel activators, veratridine and batrachotoxin. AU - Shinjo(H), Masayoshi. AU - Toshio, Nakaki. AU - Yukari, Otsuka. AU - Nobuyuki, Sasakawa. AU - Ryuichi, Kato. PY - 1991/11/26. Y1 - 1991/11/26. N2 - The effects of the sodium channel activators veratridine and batrachotoxin on isolated rat aorta were investigated. Veratridine caused gradual contraction, independent of the presence of endolhelium, with an EC50 of 35 μM. Batrachotoxin (1 μM) also induced contraction. Both effects were completely inhibited by the sodium channel blocker tetrodotoxin (1 μM). The veratridine (60 μM)-induced contraction was inhibited by nifedipine (0.1 μM). In the absence of extracellular Ca2+, veratridine (60 μm) did not cause contraction. Sodium nitroprusside (80 nM), acetylcholine (10 μM) and isoproterenol (1 μM) caused relaxation of rings precontracted with veratridine (60 μM). An inhibitor of endothelium-derived relaxing factor (EDRF) ...
Background: The magnitude of the hyperemic response due to repeated thigh stump exercise on incremental contraction intensity might be useful information in localized exercise tolerance for devising cardiovascular physical therapy for amputees. The effect of exercise on amputated leg blood flow (LBF) may potentially be altered due to voluntary muscle contractions after loss of the lower leg compared with the healthy leg. Case Presentation: A 57-year-old male patient with Burger disease attempted 3 min unilateral repeat/dynamic knee extensor exercise at a target muscle contraction frequency (1 s thigh muscle contraction and 1 s relaxation, 90 repetitions) with each leg at six different contraction intensities (rubber resistance belt). Simultaneous measurement of blood velocity/flow (Doppler ultrasound) in the femoral artery, blood pressure, leg vascular conductance (LVC), and peak muscle strength (PMS) were performed during the 3 min exercise period. The maximum voluntary contraction by one-legged
TY - JOUR. T1 - Postcontraction discharge of motor neurons in spinal animals. AU - Hutton, Robert S.. AU - Suzuki, Shuji. PY - 1979. Y1 - 1979. N2 - Muscle contraction of short duration gives rise to prolonged enhanced activity in muscle spindle afferent fibers. This postcontraction sensory discharge is sufficient in intensity to frequency-modulate motor neurons demonstrated to be tightly coupled to stretch receptors of the activated muscle. To determine whether or not postcontraction activation of motor neurons is dependent on supraspinal pathways, further experiments were done on cats with low spinal (T12) lesions. Sixty-one motor neurons were isolated in ventral root filaments and categorized according to their stretch reflex response and discharge pattern. Units found to be facilitated by stretch were significantly increased (P , 0.01) in resting discharge following contraction. Phasic motor neurons responded with a short postcontractile burst lasting only a few seconds whereas tonically ...
When the contractile properties of single muscle fibres are studied, force is typically normalized by fibre cross-sectional area and expressed as specific force. We studied a set of 2725 chemically skinned human single muscle fibres from 119 healthy adults to determine whether specific force is the optimal way to express the relationship between single-fibre force and size. A linear mixed effects model was used to estimate the slope and slope variability among individuals of log-log plots of force and diameter. For type I fibres, the slope estimate was 0.99 (95% confidence interval 0.36-1.62), and for type IIa fibres it was 0.94 (95% confidence interval 0.77-1.11), indicating that force is proportional to fibre diameter, rather than to cross-sectional area. If force were proportional to cross-sectional area, the slope estimate would be 2.0. In future studies using the chemically skinned single fibre preparation, force may be normalized to fibre diameter rather than cross-sectional area. We ...
TY - JOUR. T1 - Number of contractions to maintain mass and force of a denervated rat muscle. AU - Dow, Douglas E.. AU - Cederna, Paul S.. AU - Hassett, Cheryl A.. AU - Kostrominova, Tatiana. AU - Faulkner, John A.. AU - Dennis, Robert G.. PY - 2004/7. Y1 - 2004/7. N2 - Within 5 weeks, denervated extensor digitorum longus (EDL) muscles of rats lose 66% of mass, 91% of force, and 76% of fiber cross-sectional area (CSA). We previously determined the parameters of electrical stimulation for denervated rat EDL muscles to generate tetanic contractions sufficient to maintain mass and force close to control values. Using these parameters, we tested the hypothesis that a range exists for number of contractions per day, below and above which values for mass, maximum force, and fiber CSA are lower than values for innervated control muscles. For 5 weeks, denervated EDL muscles were stimulated to generate between 25 and 5000 contractions daily with contractions separated by constant intervals of rest, ...
The ability of a muscle to shorten and produce force is crucial for locomotion, posture, balance and respiration. During a contraction, myosin heads on the myosin filament propel the actin filament via ATP hydrolysis, resulting in shortening of the muscle and/or force generation. The maximal shortening velocity of a muscle fibre is largely determined by the myosin ATPase activity, while maximal force is primarily determined by the cross-sectional area. Since most muscles are pennate rather than parallel-fibred and work at different lever ratios, muscle architecture and joint-tendon anatomy has to be taken into account to obtain the force and velocity characteristics of a muscle. Additionally, the recruitment of agonistic and antagonistic muscles will contribute to the torque generated during a contraction. Finally, tendon compliance may impact on the rate of force rise and force generated if it is such that the muscle contraction proceeds in the ascending limb of the length-tension relation. ...
Post-activation potentiation (PAP) is a well-described phenomenon with a short half-life (~28 s) that enhances muscle force production at submaximal levels of calcium saturation (i.e., submaximal levels of muscle activation). It has been largely explained by an increased myosin light chain phosphorylation occurring in type II muscle fibers, and its effects have been quantified in humans by measuring muscle twitch force responses to a bout of muscular activity. However, enhancements in (sometimes maximal) voluntary force production detected several minutes after high-intensity muscle contractions are also observed, which are also most prominent in muscles with a high proportion of type II fibers. This effect has been considered to reflect PAP. Nonetheless, the time course of myosin light chain phosphorylation (underpinning
Airway Smooth Muscle Contraction Hyperresponsiveness to mast cell-derived mediators (eg, histamine) is a distinctive feature of asthma, but its etiology is
Various exercises require a predominance of certain muscle fiber utilization over another. Aerobic exercise involves long, low levels of exertion in which the muscles are used at well below their maximal contraction strength for long periods of time (the most classic example being the marathon). Aerobic events, which rely primarily on the aerobic (with oxygen) system, use a higher percentage of Type I (or slow-twitch) muscle fibers, consume a mixture of fat, protein and carbohydrates for energy, consume large amounts of oxygen and produce little lactic acid. Anaerobic exercise involves short bursts of higher intensity contractions at a much greater percentage of their maximum contraction strength. Examples of anaerobic exercise include sprinting and weight lifting. The anaerobic energy delivery system uses predominantly Type II or fast-twitch muscle fibers, relies mainly on ATP or glucose for fuel, consumes relatively little oxygen, protein and fat, produces large amounts of lactic acid and can ...
Contractile properties of skeletal muscle are studied for various purposes and mainly by means of force or torque twitch responses. This study compared contractile properties estimated from isometric longitudinal and transversal vastus lateralis twitch mechanical actions using torque and tensiomyography (TMG) as assessment methods, respectively. We calculated delay, contraction, sustain, half relaxation time and peak amplitude from the maximal twitch response obtained by both methods in 19 healthy males (age 46.1±17.8 years). Results indicated a shorter delay (Δ=-23.4%; p,.001) and contraction time (Δ=-42.7%; p,.001) when calculated from the transversal tensiomyographic actions, and shorter half relaxation time (Δ=-26.2%; p=.025) when calculated from the longitudinal torque actions, while no difference in sustain time was found. Delay and contraction time did not correlate significantly when correlated between longitudinal and transversal actions; however, sustain time (r=.478; p=.038) and ...
Exercise is often recommended as a means of improving motor skills, fitness, muscle and bone strength, and joint function. Exercise has several effects upon muscles, connective tissue, bone, and the nerves that stimulate the muscles. Various exercises require a predominance of certain muscle fiber utilization over another. Aerobic exercise involves long, low levels of exertion in which the muscles are used at well below their maximal contraction strength for long periods of time (the most classic example being the marathon). Aerobic events, which rely primarily on the aerobic (with oxygen) system, use a higher percentage of Type I (or slow-twitch) muscle fibers, consume a mixture of fat, protein and carbohydrates for energy, consume large amounts of oxygen and produce little lactic acid. Anaerobic exercise involves short bursts of higher intensity contractions at a much greater percentage of their maximum contraction strength. Examples of anaerobic exercise include sprinting and weight lifting. ...
Isotonic Contraction: In an isotonic contraction, the tension within the muscle remains the same throughout the motion, which is to say the force of the contraction remains constant. This is also called the positive portion of an exercise movement. There are two aspects of isotonic contraction, concentric, and eccentric. Concentric contraction occurs when the muscle fibers shorten as tension develops. At the onset of the movement, the actin and myosin filaments have tremendous pulling force. Thus you will be stronger in the initial phase of most movements. Toward the end or near the peak of contraction, the ability of the filaments to slide toward each other reaches a limit and strength weakens. An eccentric contraction is the type of muscle contraction that involves lengthening the muscle fibers, such as when a weight is lowered through a range of motion. The muscle yields to the resistance, allowing itself to be stretched. Here the actin and myosin slide away from each other. The level of ...
Thirty-six male subjects from collegiate intramural athletic teams were asked to maintain 50% of their maximum voluntary contraction on an isometric hand dynamometer as long as possible. The subjects were divided into two groups. One group performed individually while the other group, in teams of three men each, competed for a team prize. During the session, the active muscle was continuously monitored by electromyography. The results demonstrated that the introduction of the motivational factors of competition and team presence did not increase the mean endurance time. The EMG analyses indicated that muscle activity was significantly increased when additional motivational factors were introduced. It was concluded that team presence and competition are better described as stress factors which increase the general arousal level of the subject and reduce the efficiency of the muscles. (Author)(*MUSCLES
A 10-wk supplementation period with beta-alanine in adult rats caused a substantial increase in muscle carnosine and anserine levels. The increases were more pronounced for carnosine than for anserine and also more pronounced in oxidative (soleus and red gastrocnemius) than in glycolytic (white gastrocnemius) muscles. These nutritionally induced metabolic changes were accompanied by several, generally beneficial, adaptations in contractile function in MUs of the rat gastrocnemius. BA supplementation improved the twitch force of FF units and the maximum tetanic force of FR units and prolonged the half-relaxation time in slow units. As expected, it reduced the fatigability of FF units but only during the first 10 s after initiation of repeated fatiguing activity. Moreover, it enhanced the force potentiation of FR units normally observed during a standard fatigue test. Finally, supplementation reduced force decline of slow units during the first minute of repeated contractions evoked by ...
There is accumulating evidence, both in extracranial10 11 19 20 and in intracranial9 21 arteries, that TBA results in sustained arterial dilatation through a mechanism of smooth muscle cell injury and paralysis. This is consistent with other evidence that vasospasm represents active smooth muscle cell contraction22 and that it can be acutely reversed in the presence of vasodilators such as papaverine.23 24 The results of our study suggest that in vivo balloon angioplasty performed immediately before the induction of vasospasm prevents vasoconstriction after SAH and produces a functional impairment in vascular reactivity that is sustained for at least 7 days. These results are consistent with our previous report on the effects of immediate in vitro TBA9 and those of others investigating in vivo TBA performed after SAH.10 11 21 High millimolar concentration of KCl produces smooth muscle cell contraction through electromechanical coupling mechanisms with depolarization of the sarcolemma,25 whereas ...
Although smooth muscle contraction relies on the presence of Ca++ ions, smooth muscle fibers have a much smaller diameter than skeletal muscle cells. T-tubules are not required to reach the interior of the cell and therefore not necessary to transmit an action potential deep into the fiber. Smooth muscle fibers have a limited calcium-storing SR but have calcium channels in the sarcolemma (similar to cardiac muscle fibers) that open during the action potential along the sarcolemma. The influx of extracellular Ca++ ions, which diffuse into the sarcoplasm to reach the calmodulin, accounts for most of the Ca++ that triggers contraction of a smooth muscle cell.. Muscle contraction continues until ATP-dependent calcium pumps actively transport Ca++ ions back into the SR and out of the cell. However, a low concentration of calcium remains in the sarcoplasm to maintain muscle tone. This remaining calcium keeps the muscle slightly contracted, which is important in certain tracts and around blood ...
Mutungi, GM and Ranatunga, KW (1998) Effects of reducing sarcomere length on twitch contraction in mammalian (rat) muscle fibres. The Journal of Physiology, 511.P. pp. 155-156. ISSN 1469-7793 Full text not available from this repository. (Request a copy ...
A really time efficient and worthwhile type of exercise to add to your arsenal is static contraction training. Along with visualized resistance, which we have spoken of before, or with either weight training or, in my opinion the better option of bodyweight exercise, static contractions can increase your strength fast, conveniently, and effectively. ...
The vascular smooth muscle cell (VSMC) is a highly specialized cell whose principal function is contraction. On contraction, VSMCs shorten, thereby decreasing the diameter of a blood vessel to regulate the blood flow and pressure. The principal mechanisms that regulate the contractile state of VSMCs are changes in cytosolic Ca2+ concentration ([Ca2+]c). In response to vasoconstrictor stimuli, Ca2+ is mobilized from intracellular stores and/or the extracellular space to increase [Ca2+]c in VSMCs. The increase in [Ca2+]c, in turn, activates the Ca2+-CaM-MLCK pathway and stimulates MLC20 phosphorylation, leading to myosin-actin interactions and, hence, the development of contractile force. The sensitivity of contractile myofilaments or MLC20 phosphorylation to Ca2+ can be secondarily modulated by other signaling pathways. During receptor stimulation, the contractile force is greatly enhanced by the inhibition of myosin phosphatase. Rho/Rho kinase, PKC, and arachidonic acid have been proposed to ...
The vascular smooth muscle cell (VSMC) is a highly specialized cell whose principal function is contraction. On contraction, VSMCs shorten, thereby decreasing the diameter of a blood vessel to regulate the blood flow and pressure. The principal mechanisms that regulate the contractile state of VSMCs are changes in cytosolic Ca2+ concentration ([Ca2+]c). In response to vasoconstrictor stimuli, Ca2+ is mobilized from intracellular stores and/or the extracellular space to increase [Ca2+]c in VSMCs. The increase in [Ca2+]c, in turn, activates the Ca2+-CaM-MLCK pathway and stimulates MLC20 phosphorylation, leading to myosin-actin interactions and, hence, the development of contractile force. The sensitivity of contractile myofilaments or MLC20 phosphorylation to Ca2+ can be secondarily modulated by other signaling pathways. During receptor stimulation, the contractile force is greatly enhanced by the inhibition of myosin phosphatase. Rho/Rho kinase, PKC, and arachidonic acid have been proposed to ...
Figure 13 Ratio of fast type FG and FOG to slow type SO fibres in different type athletes In muscle contraction individual types of muscle fibres get activated in accordance with the intensity of muscle movement. About Podcast Contact. Leave a reply Cancel reply You must be logged in to post a comment. It is important to note here that the fibre ratio differs in different muscles of the human body. All muscle cells have a little ATP within them that they can use immediately - but only enough to last for about 3 seconds! The energy for ATP resynthesis comes from three different series of chemical reactions that take place within the body. This process creates enough energy to couple with the energy requirements to resynthesize ATP. Regardless, sport-specific conditioning plans and optimal nutritional intake need to be implemented. After maximum power declines around 12 seconds, further intense activity up to approximately 30 seconds results in lactic acid accumulation, a decrease in power, and ...
The skeletal muscles are the effector organs of the locomotor system. They are under voluntary control. Skeletal muscle is described usually as striated muscle because of its striped microscopic appearance, which results from the ordered and regular arrangement of the sub-cellular contractile elements. The stimulus for physiological skeletal muscle activity is always derived from a nerve impulse,and transported in the form of action potential, through the nervous system to the motor neuron that innervates the muscle fiber. Muscle contraction results from the interaction of actin and myosin, two filamentous proteins in the muscle cell. Energy for contraction is accumulated in the cell, and produced by aerobic and anaerobic processes during muscle contractions. This paper describes structure of skeletal muscle, and explains mechanisms of skeletal muscle contraction. It is dealing also with energy production, and muscle fatigue as well ...
Some parameters of rhythmic mechanical and electrical events of guinea-pig gall-bladder were investigated. Pressure-volume (P-V) responses, extracellular electrical activity and gall-bladder morphology were recorded. Rhythmic gall-bladder activity consisted of waves of pressure at intraluminal volumes between 0.5 and 1.8 ml. The pressure waveforms developed in a single contraction were usually oscillatory, containing two or more peaks which were more or less separated. The maximum amplitude value of phasic pressure waves was 1.8 +/- 0.6 cmH2O. Bursts of spike potentials appeared at three equidistant electrodes along the longitudinal diameter of the bladder with variable delays indicating absence of propagation of the fast electrical activity. By analysing the morphological changes of gall-bladder silhouette during the P-V curve it was evident that the maximum amplitude and duration of contractile events occurred when the whole muscular wall was stretched. Tetrodotoxin added to the bath solution did not
When training in plyometrics you need to accelerate though a complete range of motion, followed by a relaxation into a full stretch. In other words, plyometric movements require you to load your muscle then contracted in rapid sequence. You quickly stretch the muscle you are working during the initial push-off. This is thought to increase muscle contraction, thus increasing power generation.. For movement to occur a muscle must shorten which is known as concentric contraction. However, there is a maximum amount of force or limit to which the muscle can concentrically contract. Now if the muscle can be lengthened while being loaded (i.e. eccentric phase) just prior to the muscle contraction, it will produce a greater force though the storage of elastic energy. That is, the time between the two phases, (concentric contraction and eccentric phases) must be very short.. Plyometric exercises develop explosive power due to this quick release of energy by the muscles. However, plyometrics should not be ...
TY - JOUR. T1 - Changes in end-to-end interactions of tropomyosin affect mouse cardiac muscle dynamics. AU - Gaffin, Robert D.. AU - Gokulan, Kuppan. AU - Sacchettini, James C.. AU - Hewett, Timothy E.. AU - Klevitsky, Raisa. AU - Robbins, Jeffrey. AU - Sarin, Vandana. AU - Zawieja, David C.. AU - Meininger, Gerald A.. AU - Muthuchamy, Mariappan. PY - 2006. Y1 - 2006. N2 - The ends of striated muscle tropomyosin (TM) are integral for thin filament cooperativity, determining the cooperative unit size and regulating the affinity of TM for actin. We hypothesized that altering the α-TM carboxy terminal overlap end to the β-TM counterpart would affect the amino-terminal association, which would alter the end-to-end interactions of TM molecules in the thin filament regulatory strand and affect the mechanisms of cardiac muscle contraction. To test this hypothesis, we generated transgenic (TG) mouse lines that express a mutant form of α-TM in which the first 275 residues are from α-TM and the last ...
Birba A, Hesse E, Sedeño L, Mikulan EP, García MDC, Ávalos J, Adolfi F, Legaz A, Bekinschtein TA, Zimerman M, Parra M, García AM, Ibáñez A. Enhanced Working Memory Binding by Direct Electrical Stimulation of the Parietal Cortex. Front Aging Neurosci. 2017 Jun 8;9:178. doi: 10.3389/fnagi.2017.00178 La memoria de trabajo de integración (WMB) es un marcador preclínico de la enfermedad de Alzheimer (EA) que depende de regiones posteriores del cerebro. La estimulación de la corteza parietal posterior (PPC) podría ser un target terapéutico en la EA. En este estudio, encontramos que la estimulación eléctrica y directa intracraneal de regiones específicas de la PPC durante la WMB induce una mejora selectiva en el desempeño.
Autor: Borchers, S et al.; Genre: Zeitschriftenartikel; Im Druck veröffentlicht: 2012-01; Titel: Direct electrical stimulation of human cortex: the gold standard for mapping brain functions?
BioAssay record AID 71785 submitted by ChEMBL: Percent block of sciatic nerve sartorius muscle twitch of frog 60 min after indirect stimulation and exposure to 50 uM toxin for 60 min.
Dynamic force generation in cardiac muscle, which determines cardiac pumping activity, depends on both the number of sarcomeric cross-bridges and on their cycling kinetics. The Frank-Starling mechanism dictates that cardiac force development increase
New research involving people diagnosed with Lou Gehrigs disease sheds light on how individual neurons control muscle movement in humans - and could help in the development of better brain-controlled prosthetic devices.
You searched for: Exhibit Tags institute Remove constraint Exhibit Tags: institute Genre Articles Remove constraint Genre: Articles Language English Remove constraint Language: English Periodical Science Remove constraint Periodical: Science Subject Muscle Contraction Remove constraint Subject: Muscle Contraction ...
Airway smooth muscle (ASM) contraction is a major contributor to bronchoconstriction, the narrowing of the airways observed in asthmatic airways. In vitro, ASM cells demonstrate the capacity to switch between more proliferative and more contractile phenotypes, and changes to ASM contractile function, potentially as a consequence of this phenotypic switching, may play a significant role in the exaggerated airway narrowing observed in asthma. In vivo, airway epithelial (AE) cells are topographically close to the ASM and may modulate and regulate ASM phenotype and function that could be dysregulated in asthma. One important mediator increased in asthma is TGF-β1, which influences AE cell phenotype and thus possibly affects AE cell effects on ASM. In this work, we investigated the effects of AE, with and without the influence of TGF- β1, on ASM contractile function. After examining the response of AE and ASM to TGF-β1 individually, one-way and two-way communication modes between the cell types ...
Purpose: The purpose of this study was to investigate the origins of differing tonic muscle activity in three populations with known differences in neuromuscular processing. Methods: We manipulated healthy young adults, healthy older adults and individuals with Parkinsons disease (PD), both on and off dopamine therapy medication, with a novel technique related to muscle after contraction (MAC). We also investigated the transfer of tonic activity to the contralateral (unmanipulated) limbs to determine whether tonic activity is modulated through inhibitory and facilitatory interneuronal processes at a peripheral, spinal, or supraspinal level. In independent trials, we examined MAC in both proximal (medial deltoid) and distal (tibialis anterior) postural musculature by having subjects perform a voluntary, isometric contraction of the upper arm or ankle, respectively. Using surface electromyography (sEMG) to record the activity of the motor units before, during and after contraction, we were able ...
Currently I am looking into what muscles groups are most used during a football kick. I have a hypothesis that the quadriceps are not as used as most people think because the momentum the swing creates makes the knee extend to fast for the quadriceps to contract.. To prove this I need to know the speed the knee extends during a football kick and the time it takes for the quadriceps to contract. I know how fast the knee extends through my own research. Does anyone have any information on the speed of muscle contraction? Quadriceps contraction time would be optimal, but any information relevant would be very helpful. ...
A nonwoven web material that includes an elastic component or material (e.g., nonwoven web, nonwoven web laminated to an elastic material, etc.) is provided. The elastic component contains a crosslinked network formed from a pentablock copolymer containing at least two monoalkenyl aromatic midblocks positioned between conjugated diene endblocks, such as butadiene-styrene-butadiene-styrene-butadiene (
Contraction of muscles generates tension, which allows muscles to shorten and thereby perform work.The contraction strength of skeletal muscles must be
Sweeney HL, Hammers DW (February 2018). "Muscle Contraction". Cold Spring Harbor Perspectives in Biology. 10 (2): a023200. doi: ... Rhabdomyosarcoma is a sarcoma of composed of skeletal muscle cells; irregular growth in the primitive form of these skeletal ... These neoplastic cells yield positive results for vimentin, smooth muscle actin, and desmin stains; however, myoglobin, myoD1 ... Immunohistochemistry techniques allow for the sensitive detection of desmin, vimentin, muscle specific actin, and MyoD1. ...
In muscle cells, for example, an action potential is the first step in the chain of events leading to contraction. In beta ... "Cardiac Muscle Contraction". Retrieved 28 May 2021. Pickard B (June 1973). "Action Potentials in Higher Plants" (PDF). The ... This enzyme quickly reduces the stimulus to the muscle, which allows the degree and timing of muscular contraction to be ... which then produces muscle contraction. Nearly all cell membranes in animals, plants and fungi maintain a voltage difference ...
Psychogenic hypothesis: emotions, such as stress, causing contraction in skeletal muscles. The vertebral subluxation has been ... muscle contraction or imbalance; altered physiological function; reversible with adjustment/manipulation; focal tenderness. ...
... heart muscle contraction performance; and some aspects of heart valve function. Important internal heart and lung blood ... Less frequently, valvular, heart muscle, or arrhythmia issues are the primary focus of the test. Coronary artery luminal ...
... involuntary contractions may involve the muscles used for chewing (masticatory muscles). These may include the thick muscle in ... temporalis muscle). Some patients may also experience involuntary contractions of the wide muscle at the side of the neck ( ... platysmal muscle). This muscle draws down the corner of the mouth and lower lip or other muscle groups.[citation needed] In ... The Greek word blepharon means "eyelid". Spasm means "uncontrolled muscle contraction". The term blepharospasm ['blef-a-ro-spaz ...
Spudich JA, Huxley HE, Finch J (1972). "Regulation of skeletal muscle contraction. II. Structural studies of the interaction of ... Spudich JA, Watt S (1971). "The Regulation of Rabbit Skeletal Muscle Contraction". Journal of Biological Chemistry. 246 (15): ... of Biochemistry and of Cardiovascular Disease at Stanford University and works on the molecular basis of muscle contraction. He ... A brief history of muscle biology 1864-1969". Retrieved 2 June 2020. Zubrinic, Darko. "James Spudich American scientist of ...
The muscles then contract through the sliding filament mechanism, causing shortening of sarcomeres and muscle contraction. ... Webb RC (December 2003). "Smooth muscle contraction and relaxation". Advances in Physiology Education. 27 (1-4): 201-6. doi: ... When these cells are depolarized, the L-type calcium channels open as in smooth muscle. In skeletal muscle, the actual opening ... "Thromboxane A2-induced contraction of rat caudal arterial smooth muscle involves activation of Ca2+ entry and Ca2+ ...
Webb, RC (December 2003). "Smooth muscle contraction and relaxation". Advances in Physiology Education. 27 (1-4): 201-6. doi: ... Directly relax the muscle in the walls of the blood vessels (especially the arterioles), allowing the vessel to dilate (widen ... However, it has been shown that knocking out this sympathetic stimulation plays little or no role in whether skeletal muscle is ... It results from relaxation of smooth muscle cells within the vessel walls, in particular in the large veins, large arteries, ...
Muscle contraction is stimulated by the motor neuron sending a message to the muscles from the somatic nervous system. ... Cardiac muscles are found in the heart and are used only to circulate blood; like the smooth muscles, these muscles are not ... Bárány, Michael (2002). "SMOOTH MUSCLE". Retrieved 19 November 2008. "The Mechanism of Muscle Contraction". Principles of Meat ... Skeletal muscles are attached to bones and arranged in opposing groups around joints. Muscles are innervated, to communicate ...
Is titin a 'winding filament'? A new twist on muscle contraction. Kiisa C Nishikawa, Jenna A Monroy, Theodore E Uyeno, Sang ... "NAU physiologist publishes findings on the role of the protein titin in muscle contraction - NAU News". Retrieved 2020-03-07. ... where her laboratory investigates muscle contraction, including the role of titin and developing bio-inspired control ... Retrieved 2020-03-07.{{cite news}}: CS1 maint: url-status (link) "Atomic force microscope will investigate muscle movement at ...
This increases the muscle contraction strength. Additionally, within minutes, cell metabolism and gene expression, which are ... In this phase of the cardiac cycle, electrical signals cannot trigger new cardiac muscle contractions, hence this type of ... The short- and long-term use of this therapy enhances the strength of ventricular contraction and therefore the heart's pumping ... Studies on individual cardiac muscle cells using a patch-clamp technique had already shown, in 1969, that a voltage applied ...
"Structural changes in muscle during contraction; interference microscopy of living muscle fibres". Nature. 173 (4412): 971-973 ... leading to the sliding filament model of muscle contraction. Interference microscopy became relatively popular in the 1940-1970 ... which was first effectively exploited by Andrew Huxley in studies of striated muscle cell structure and function, ...
Smooth muscle contraction in the gut. Probable role in sleep paralysis. Activation of the 5-HT2A receptor is necessary for the ...
... which cause the contraction of skeletal muscles. These equations presented an entirely new paradigm for understanding muscle ... into a detailed description of muscle structure and how muscle contraction occurs and generates force that he published in 1957 ... "Structural changes in muscle during contraction; interference microscopy of living muscle fibres". Nature. 173 (4412): 971-3. ... He, however, was able to make interference microscopy work and to apply it to the problem of muscle contraction with great ...
Some examples include: Huxley, A.F. (1957). "Muscle Structure and Theories of Contraction". Progress in Biophysics and ... Woledge, Roger C. (1971). "Heat Production and chemical change in muscle". Progress in Biophysics and Molecular Biology. 22: 37 ... and the mechanical and thermal properties of muscle fibre operation. When Randall stepped down in 1957 he was succeeded by Sir ...
Chapman, RA (January 1980). "Excitation-contraction Coupling in Cardiac Muscle". Progress in Biophysics and Molecular Biology. ... which are then transmitted to cardiac muscle cells to induce contraction. After depolarization, the ions are moved back to ... Mutations resulting in loss of function of K+ channels can result in delayed repolarization of the cardiac muscle cells. ... and cardiac muscle, to mutations in genes coding for ion channels of the heart. Movement of ions, particularly Na+, Ca2+ and K+ ...
Sliding Filament Mechanism in Muscle Contraction. Advances in Experimental Medicine and Biology. Vol. 565. pp. 283-92, ... ALC-1 is expressed very early in skeletal muscle and cardiac muscle development; two E-boxes and CArG box in the MYL4 promoter ... ALC-1 is expressed in fetal cardiac ventricular and fetal skeletal muscle, as well as fetal and adult cardiac atrial tissue. ... ALC-1 is expressed in fetal cardiac ventricular and fetal skeletal muscle, as well as fetal and adult cardiac atrial tissue. ...
A 0 is for no muscle contraction. A 1 is for a flicker or trace of contraction in a muscle. A 2 is for active movement in a ... muscle strength is tested using the bench press for a variety of spinal cord related injuries with a muscle being assessed on a ... In 2002, USA Track & Field defined this class as, "These athletes have no hand function, are unable to use the muscles that ... The sixth test measures the trunk extension involving the lumbar and dorsal muscles while leaning forward at a 45 degree angle ...
This event allows the muscle fibers to overlap, causing a contraction. In BD, Ca2+ levels are high in the cytoplasm, which ... Skeletal muscle biopsies are used to examine muscle fibers. Biopsies in individuals with BD often show variation in muscle ... Increases in cytoplasmic Ca2+ levels interfere with muscle contraction, leading to the characteristic symptoms of BD. In some ... "Sliding Filament Theory, Sarcomere, Muscle Contraction, Myosin , Learn Science at Scitable". www.nature.com. Retrieved 2018-09- ...
... that are integral to muscle contraction in skeletal muscle and cardiac muscle, but not smooth muscle. Measurements of cardiac- ... and contraction of the muscle begins. Troponin is found in both skeletal muscle and cardiac muscle, but the specific versions ... playing the main role in Ca2+ dependent regulation of muscle contraction. TnT and TnI in cardiac muscle are presented by forms ... In a relaxed muscle, tropomyosin blocks the attachment site for the myosin crossbridge, thus preventing contraction. When the ...
He attributed this muscle contraction to irritability, which he described as being an inherent power. He particularly made the ... One example is the muscle and contraction. Various explanations on a macroscopic and microscopic scale were made to explain how ... and differences in muscles across living things and his understanding of the underlying mechanism of muscle contraction, ... thus the muscle changed shape at a fixed volume by only changing the angles between each fibre. This explanation of contraction ...
37: Mechanism of Muscle Contraction" (PDF). Cold Spring Harbor Symposia on Quantitative Biology. Retrieved 8 Feb 2015. "List of ... His research focused on the biochemistry and cellular physiology of muscle contraction and nerve transmission. In retirement ... 1990). Tissue culture of squid neurons, glia, and muscle cells. pp. 195-212. In: D.L. Gilbert, W.J. Adelman and M. Arnold (eds ... Kelly, R.E. and R.V. Rice (1968). Localization of myosin filaments in smooth muscle. Journal of Cell Biology 37(1):105-116. ...
A 0 is for no muscle contraction. A 1 is for a flicker or trace of contraction in a muscle. A 2 is for active movement in a ... muscle strength is tested using the bench press for a variety of spinal cord related injuries with a muscle being assessed on a ... A 5 is for normal muscle movement. Sports portal National Governing Body for Athletics of Wheelchair Sports, USA. Chapter 2: ... poke and prod their muscles with their hands and with pins. The system had no built in privacy safeguards and players being ...
For example, it regulates the contraction of muscles, nerve conduction, and the clotting of blood. As a result, intra- and ... in contraction of all muscle cell types; as cofactors in many enzymes; and in fertilization. Calcium ions outside cells are ... Symptoms include anorexia, nausea, vomiting, memory loss, confusion, muscle weakness, increased urination, dehydration, and ...
At the organ level blebbistatin stops the contraction of skeletal muscle or heart muscle. Blebbistatin has also been found to ... It is widely used in research to inhibit heart muscle myosin, non-muscle myosin II, and skeletal muscle myosin. Blebbistatin ... contraction of skinned tracheal muscles from guinea pig". Journal of Smooth Muscle Research = Nihon Heikatsukin Gakkai Kikanshi ... "Potent inhibition of arterial smooth muscle tonic contractions by the selective myosin II inhibitor, blebbistatin". The Journal ...
Davydov, Alexander S. (1979). "Solitons, bioenergetics, and the mechanism of muscle contraction". International Journal of ... Davydov, Alexander S. (1973). "The theory of contraction of proteins under their excitation". Journal of Theoretical Biology. ...
For example, botulinum injections paralyze facial muscles. This prevents muscle contraction and subsequent wrinkle formation. ...
Structural basis of contraction in vertebrate smooth muscle. J Mol Biol. 1972 Jun 14; 67(1):117-149. Squire JM. General model ... The main focus of his research was on the structural basis of muscle contraction. His early contributions were the proposal of ... His final works were on the unresolved problem of how myosin and actin molecules interact to bring about muscle contraction, as ... where he researched muscle contraction and blood vessel glycocalyx structure. He was a Fellow of both the Institute of Physics ...
EMS units are designed to cause muscle contraction. An increasing number of "body toner" or "electromassage"-type power sources ... The international standard on the basic safety of medical nerve and muscle stimulators advises "that stimulation should not be ... electrical muscle stimulation) units. Some people soon found alternative uses for the Relax-A-Cizors by placing the contacts on ... which was originally designed to stimulate the muscles of a relaxing subject using electric currents as a means of "passive ...
It also causes muscle contractions. HEY, P (March 1952). "On relationships between structure and nicotine-like stimulant ... WILLEY, GL (December 1955). "Stimulant activities of quaternary ammonium compounds on mammalian skeletal muscle". British ...
This is a neurotransmitter which plays a necessary role in muscle contraction, memory and neural development, for example.[6] ... Severe deficiency causes muscle damage and non-alcoholic fatty liver disease, which may develop into cirrhosis.[28] ... Symptomatic choline deficiency - rare in humans - causes nonalcoholic fatty liver disease and muscle damage.[4] Excessive ... muscles and heart. They are associated with the mitochondrial oxidation of choline to trimethylglycine. CTL1s and CTL2s are not ...
IL-6 is also considered a myokine, a cytokine produced from muscle, which is elevated in response to muscle contraction.[27] It ... "Muscle contractions induce interleukin-6 mRNA production in rat skeletal muscles". The Journal of Physiology. 528 Pt 1: 157-163 ... muscle contractions. This finding clearly demonstrates that muscle damage is not required to provoke an increase in plasma IL-6 ... IL-6 was the first myokine that was found to be secreted into the blood stream in response to muscle contractions.[33] Aerobic ...
Muscle contraction[edit]. Physiology of muscle contraction involves several interactions. Myosin filaments act as molecular ... motors and by binding to actin enables filament sliding.[8] Furthermore, members of the skeletal muscle lipid droplet- ...
2][3]The tunica adventitia contains three zones, with the middle zone consisting of few smooth muscle fibers; this differs from ... As a result, the (right) atrial and (right) ventricular contractions are conducted up into the internal jugular vein and, ... The middle layer is the tunica media, composed of smooth muscle tissue, and the outermost and thickest layer is the tunica ... through the sternocleidomastoid muscle, can be seen as the jugular venous pressure. ...
... and is operated by a complex set of muscles inserting into cartilages of the neurocranium, assisted by peristaltic contractions ... In particular, hagfish muscles have increased force and gape size compared to similar-sized jawed vertebrates, but lack the ... The hagfish eye lacks a lens, extraocular muscles, and the three motor cranial nerves (III, IV, and VI) found in more complex ... Robertson, J.D (1976), "Chemical composition of the body fluids and muscle of the hagfish Myxine glutinosa and the rabbit-fish ...
The most important muscle involved is the orbicularis oris muscle, which is used to pucker the lips and informally known as the ... Research indicates that contraction of HIV via kissing is extremely unlikely, although there was a documented case in 1997 of ... "orbicularis oris muscle". TheFreeDictionary: Mosby's Dental Dictionary, 2nd edition. 2008. Retrieved 3 October 2010.. ... Men will give themselves away by a certain excited trembling in the muscles of the lower jaw upon seeing their beloved. Women ...
Hulbert AJ, Faulks S, Buttemer WA, Else PL (November 2002). "Acyl composition of muscle membranes varies with body size in ... are distributed to cells to serve as a fuel for muscular contraction and general metabolism. ...
... possible spreading due to muscle contractions), but cross contamination with the electrodes themselves is of greater concern.[ ... A strong but painless sensation of strained muscles Top of the muscle in a sore muscle area to activate the motor nerves. ... For the muscle stimulation device, see Electrical muscle stimulation.. "TENS" redirects here. For other uses, see TENS ( ... It may also cause skin irritation due to the inability to feel currents until they are too high.[52] There's an unknown level ...
positive regulation of cardiac muscle contraction. *regulation of inflammatory response. *positive regulation of gap junction ...
As the silent performance required expressive eyes, a new eye model was made to depict both greater accuracy in muscle movement ... and there's a lot more stories to tell after this. I imagine the next film will be about the all-out war between the apes and ... The digital apes also received detailed models with skeletons, muscles and nerve tissue layers for accurate animation. Cast ... Given the difference between human and chimpanzee facial muscles, the animators tweaked the performance through a new facial ...
A 50% solution of DMSO had the potential to create irreversible muscle contraction. However, a lesser solution of 25% was found ... The goal of therapy is to relax and lengthen the pelvic floor muscles, rather than to tighten and/or strengthen them as is the ... Urologic pelvic pain syndromes, such as IC/BPS and CP/CPPS, are characterized by pelvic muscle tenderness, and symptoms may be ... A therapeutic wand can also be used to perform pelvic floor muscle myofascial release to provide relief.[48] ...
... ultimately causing smooth muscle contraction.[34] In order to activate contraction of smooth muscle, the head of the myosin ... Walsh MP (June 1994). "Calmodulin and the regulation of smooth muscle contraction". Molecular and Cellular Biochemistry. 135 (1 ... This MLC kinase is activated by a calmodulin when it is bound by calcium, thus making smooth muscle contraction dependent on ... Another way that calmodulin affects muscle contraction is by controlling the movement of Ca2+ across both the cell and ...
This leads to the actual contraction of the muscle.[15] Contractions of smooth muscle fiber are dependent on how a Ca2+ influx ... Contractions of skeletal muscle fiber are caused due to electrical stimulation. This process is caused by the depolarization of ... When a Ca2+ influx occurs, cross bridges form between myosin and actin leading to the contraction of the muscle fibers. ... Calcium is a ubiquitous second messenger with wide-ranging physiological roles.[2] These include muscle contraction, neuronal ...
In both types the modified operculum is opened by other muscles that attach to it,[27] or by internal muscles that raise the ... Wave-like peristaltic contractions move the food through the stomach for digestion. The final section of the stomach is lined ... The invert is withdrawn, sometimes within 60 milliseconds, by a pair of retractor muscles that are anchored at the far end of ... The body wall consists of the epidermis, basal lamina (a mat of non-cellular material), connective tissue, muscles, and the ...
... which is involved in striated muscle formation. In nature, DNA molecules can be much bigger than protein molecules and ... There's a little bit of floccinaucinihilipilification going on here." *^ Eckler, R. Making the Alphabet Dance, p 252, 1996. ...
"Here's Proof That Crowdfunding Pays Off". Fortune. Retrieved March 15, 2019.. *^ "AngelList Unveils Maiden Lane, A $25 Million ... "Angels Muscling In on VC Turf". Wall Street Journal. ISSN 0099-9660. Retrieved May 4, 2018 ...
When the heart muscle contracts (pushes in) it is called systole. When the heart muscle relaxes (stops pushing in), this is ... It has regular contractions, or when the heart squeezes the blood out into other parts of the body. ... Myocardium means the heart muscle: 'myo' is from the Greek word for muscle - 'mys', cardium is from the Greek word for heart ... Once the bundle (meaning a group of strings or wires going in parallel directions) goes through the ventricle muscle, it ...
Bolen, J. G., (1980-12-09). "The male orgasm: pelvic contractions measured by anal probe". Archives of Sexual Behavior (6): 503 ... Assessment of the electromyographic activity of the bulbocavernosus and ischiocavernosus muscles". British Journal of Urology. ...
... these receptor channels allow sodium ions into muscle cells to initiate an action potential that leads to muscle contraction. ... As a result, the muscle cells contract permanently, the communication between the brain and the muscles is disrupted and ... a b Brin, Mitchell F (1997) "Botulinum Toxin: Chemistry, Pharmacology, Toxicity, and Immunology." Muscle & Nerve, 20 (S6): 146- ... Once it has triggered a contraction, anatoxin-a does not allow the neurons to return to their resting state, because it is not ...
The probe measures muscle contractions in different parts of the esophagus during the act of swallowing. Manometry reveals ... The innermost circular muscle layer of the esophagus is divided and extended through the LES until about 2 cm into the gastric ... Esophageal achalasia, often referred to simply as achalasia, is a failure of smooth muscle fibers to relax, which can cause the ... The lower esophageal sphincter is a muscle between the esophagus and stomach that opens when food comes in. It closes to avoid ...
The right heart is a solid mass of muscle which provides most of the force behind the body's blood circulation. The left heart ... "There's No Hiding Place Down here"-about the inevitability of the punishment of a fleeing sinner. William Forward asked J. ...
Intramuscular administration is not recommended due to small muscle mass.[31] Intracerebral administration is also possible. ... "There's more to life than rats and flies". Nature. Retrieved 6 August 2015 ...
Mechanical work in muscles Muscle contraction model Founding biophysics. Hill equation (biochemistry). ...
... move to the underlining smooth muscle, and reverse the smooth muscle contraction caused by TXA2 by functioning as a Receptor ... move to underlying smooth muscles, and trigger a response of Hyperpolarization (biology)-induced relaxation by binding to and ...
... characterized by involuntary extension and contractions of the muscles of the feet that cause the bird to constantly tap its ...
Muscular thin films (MTF) enable cardiac muscle monolayers to be engineered on a thin flexible substrate of PDMS.[40] In order ... Collagen tends to detach from the microfluidic backbone during culturing due to the contraction of fibroblasts. One study ... The multiple inputs from a microenvironment cause a wide range of mechanical or chemical stimuli on the smooth muscle cells ( ... The contraction rate of human induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CM) is observed to accelerate with ...
... various parts of the heart muscle with different timing than usual and can be responsible for poorly coordinated contraction.[ ... Extra beats include premature atrial contractions, premature ventricular contractions and premature junctional contractions.[3] ... Premature junctional contraction. Ventricular arrhythmia[edit]. *Premature ventricular contractions (PVCs), sometimes called ... Automaticity refers to a cardiac muscle cell firing off an impulse on its own. All of the cells in the heart have the ability ...
"Muscle from Brussels as open access gets an €80bn boost". Times Higher Education (THE). 17 May 2012. Retrieved 26 March 2017.. ... there's evidence suggesting that reliability of published research works in several fields may decrease with increasing journal ...
The flap is closed during muscle relaxation and opens during contraction.[93] Dolphins are voluntary breathers, who must ... The flukes (lobes of the tail) and dorsal fin are formed of dense connective tissue and do not contain bone or muscle. The ...
Mannies, Jo (March 18, 2008). "Ron Paul's Missouri Backers Muscle Up: They Say Caucus Strategy was to Get GOP to Return to ... there's no proposal for any real cuts and both parties support it."[145] Paul received 26,204 write-in votes, or 0.02% of the ...
encoded search term (Muscle Contraction Tension Headache) and Muscle Contraction Tension Headache What to Read Next on Medscape ... Muscle Contraction Tension Headache. Updated: May 21, 2019 * Author: Syed M S Ahmed, MD; Chief Editor: Tarakad S Ramachandran, ... Muscle contraction (tension) headache. Clin J Pain. 1989. 5(1):39-44. [QxMD MEDLINE Link]. ... Hypoalgesic effect of caffeine in experimental ischemic muscle contraction pain. Headache. 1997 Nov-Dec. 37(10):654-8. [QxMD ...
encoded search term (Muscle Contraction Tension Headache) and Muscle Contraction Tension Headache What to Read Next on Medscape ... Muscle Contraction Tension Headache Differential Diagnoses. Updated: May 21, 2019 * Author: Syed M S Ahmed, MD; Chief Editor: ... Muscle contraction (tension) headache. Clin J Pain. 1989. 5(1):39-44. [QxMD MEDLINE Link]. ... Hypoalgesic effect of caffeine in experimental ischemic muscle contraction pain. Headache. 1997 Nov-Dec. 37(10):654-8. [QxMD ...
regulation of striated muscle contraction + skeletal muscle contraction + A process in which force is generated within skeletal ... involuntary skeletal muscle contraction + regulation of excitatory postsynaptic membrane potential involved in skeletal muscle ... In the skeletal muscle, the muscle contraction takes advantage of an ordered sarcomeric structure and in most cases it is under ... skeletal muscle contraction (GO:0003009). Annotations: Rat: (53) Mouse: (51) Human: (54) Chinchilla: (42) Bonobo: (45) Dog: (51 ...
A typical muscle fiber at rest contains enough ATP for millions of contractions. ... Iron and fats bound to actin play a critical role in muscle cell contraction and relaxation. ... Muscle Fibre types Slow twitch and Fast twitch GCSE PE in 3 revision in 3 minutes ... GCSE PE - MUSCLE FIBRE TYPES - Anatomy and Physiology (Skeletal and Muscular System - 1.6) ...
Heres a few more looks from the past couple offseasons of Syndergaard crushing it in the gym:. 3. Getting into the holiday ... How did he do it? Syndergaard used the all-Paleo, protein-packed Bowl of Doom to pack on the muscle. Find out whats in it.) ... This time around he continued to push hard in the gym, but to make sure he gained the muscle and weight he wanted, Syndergaard ... This winter, Syndergaard has packed on even more muscle.. In fact, he added nearly 20 pounds of it. ( ...
It was developed to enable continuous monitoring of knee joint mechanics and the associated muscles during free-living ... We developed an algorithm for simulating muscle contraction during gait using only wearable sensors. ...
... tired and lose muscle as we age is because our testosterone levels slowly dwindle away. This leads to a whole ... This clinical trial found that Panax Ginseng helps boost muscle protein synthesis and increases strength and muscle mass. ... Heres a brief rundown of the research behind each key ingredient:. *D-Aspartic Acid: D-Aspartic Acid has been shown to ... My TestoFuel Results - Heres What Happened When I Tried It. Courtesy of Musclepursuit.com. After reading all the testimonials ...
Theres no need to put on unnecessary fat this holidays! This article contains 25 easy nutrition and exercise tips you can ... By depleting muscle glycogen (re: carbohydrate for muscle cells) levels youll help to offset the increased caloric intake that ... Theres a delay between consumption of food and feelings of satiety. If you rush to eat, you may be more inclined to ignore ... Theres a delay between consumption of food and feelings of satiety.. Strategy #4 - Dont Skip Dessert; Be Smart About Dessert ...
The vascular smooth muscle cell (VSMC) is a highly specialized cell whose principal function is contraction. On contraction, ... Vascular smooth muscle contraction - Homo sapiens (human) [ Pathway menu , Organism menu , Pathway entry , Download KGML , Show ...
... in myosin phosphatase inihibition and smooth muscle contraction. Molecular and Cellular Biochemistry, 327, 93 - 100. ... in myosin phosphatase inihibition and smooth muscle contraction. ... in myosin phosphatase inihibition and smooth muscle contraction ...
Contraction frequency modulates muscle fatigue and the rate of myoglobin desaturation during incremental contractions in humans ... "Contraction frequency modulates muscle fatigue and the rate of myoglobin desaturation during incremental contractions in humans ...
Effects of phasic and tonic activation on contraction dynamics in smooth muscle. *Mark ... Effects of phasic and tonic activation on contraction dynamics in smooth muscle}}, volume = {{109}}, year = {{1980}}, } ... Releases were performed at peak of the contractions (which was attained after 1.5-4.5 s AC-stimulation or 2-3 min in K+-high ... Releases were performed at peak of the contractions (which was attained after 1.5-4.5 s AC-stimulation or 2-3 min in K+-high ...
"A Piezoresistive Sensor to Measure Muscle Contraction and Mechanomyography",. abstract = "Measurement of muscle contraction is ... N2 - Measurement of muscle contraction is mainly achieved through electromyography (EMG) and is an area of interest for many ... AB - Measurement of muscle contraction is mainly achieved through electromyography (EMG) and is an area of interest for many ... Measurement of muscle contraction is mainly achieved through electromyography (EMG) and is an area of interest for many ...
... is whether or not a muscle repair is included ... How a muscle repair impacts recovery. When a muscle repair is ... Why the muscle sometimes needs a repair. If you have seen the abs on even one superhero you will know the muscle we are talking ... Why the muscle sometimes doesnt need a repair. Not all tummy tucks include a muscle repair because not all bellies that can ... Why a muscle repair impacts tummy tuck recovery. The difference in recovery between a tummy tuck with muscle repair versus one ...
Muscle Contraction - Cross Bridge Cycle Animation.. How tropomyosin and troponin regulate muscle contraction , NCLEX-RN , Khan ... Class 11 Biology Muscle Contraction. The Mechanism of Muscle Contraction: Sarcomeres Action Potential and the Neuromuscular ... Muscle Contraction - Cross Bridge Cycle Animation.. *How tropomyosin and troponin regulate muscle contraction , NCLEX-RN , Khan ... Class 11 Biology Muscle Contraction. *The Mechanism of Muscle Contraction: Sarcomeres Action Potential and the Neuromuscular ...
Muscle Protein Breakdown Vs. Muscle Protein Synthesis. Muscle is constantly being broken down (muscle protein breakdown; MPB) ... Your Muscles Start Shrinking in Your 30s. Heres What To Do About it. Hang onto precious muscle mass through training and diet ... Eat to Build Muscle. The muscle-loss part of the equation accelerates around age 50. Before that, your muscle cells are still ... and rebuilt (muscle protein synthesis; MPS). Muscle loss occurs when the balance tips toward breakdown. How is muscle protein ...
Heres how the name-calling, muscle-flexing dispute began.. Suzy Byrne. ·Editor, Yahoo Entertainment ... One part of me feels like theres no way I would dignify any of that bulls*** with an answer. But heres the truth: Ive been ... Heres the deal on why Dwayne "The Rock" Johnson and Vin Diesel - seen here at the Rio premiere of Fast 5 in 2011 - dont get ... And if I feel that theres some things that need to be squared away and handled and taken care of, then I do it. And its just ...
Reflex excitability of human soleous muscle following repeated ballistic contraction. Research Project ... and then was increased more than the test reflex before muscle contraction. The faciltation sustained throughout 30 to 40 min. ... Motoneuron excitablity / H-reflex / Ballistic contraction / Human / 随意収縮 / Hoffman反射 / 抑制現象 / 運動ニューロン. ... 2. Immediately after the repeated ballistic contractions, H-reflexe was remarkably depressed accompanied by restoring phase, ...
Is concerta less likely going to cause smooth muscle contraction than ritalin (methylphenidate)?. 1 doctor answer • 4 doctors ... 40mg Ritalin (methylphenidate) for ADD & have chronic muscle tension. PCP Rx 10mg baclofen & 300mg daily Mg for intense jaw ...
A Method to Measure Elicited Contraction of Laryngeal Adductor Muscles during Anesthesia François Donati, Ph.D., M.D., F.R.C.P. ... François Donati, Benoît Plaud, Claude Meistelman; A Method to Measure Elicited Contraction of Laryngeal Adductor Muscles during ... Mivacurium Neuromuscular Block at the Adductor Muscles of the Larynx and Adductor Pollicis in Humans Anesthesiology (July 1996) ... ORG 9487 Neuromuscular Block at the Adductor Pollicis and the Laryngeal Adductor Muscles in Humans Anesthesiology (June 1997) ...
RhoA, a regulator of airway smooth muscle contractility, was activated in airway smooth muscle lysates from Iqgap1-/- mice. ... inactivating RhoA and suppressing airway smooth muscle contraction. Furthermore, our results suggest that IQGAP1 has the ... Here, we determined that IQGAP1 modulates airway smooth muscle contractility. Compared with WT controls, at baseline as well as ... Proximity ligation assays in primary airway human smooth muscle cells and mouse tracheal sections revealed colocalization of ...
... muscle) fatigue. This study sought to compare parameters of peripheral and central fatigue resulting from RAPID and RAMP MVICs ... Varying muscle contraction speed may uniquely affect central (nervous system) and peripheral ( ... Varying muscle contraction speed may uniquely affect central (nervous system) and peripheral (muscle) fatigue. This study ... Varying muscle contraction speed may uniquely affect central (nervous system) and peripheral (muscle) fatigue. This study ...
Heres the Answer - Legal Steroids Presents Gearin Up 1/8/20 ... Calves Wont Grow? Heres the Answer - Legal Steroids Presents ... Home / MuscleSport TV / Gearing Up / Calves Wont Grow? Heres the Answer - Legal Steroids Presents Gearin Up 1/8/20 ... 1/8/20Calvesgearin upGrowHeres the AnswerinstagramLegal SteroidsPresentsWont ... http://www.legalsteroids.com USE CODE MUSCLE VIDEO 30 TO SAVE 30% ...
Eccentric contraction - muscle lengthens as reistance surpasses force generated. Isometric contraction - muscle stays the same ... This is what most people think of as a muscle contraction.. *In eccentric contraction, the force generated is insufficient to ... When its all gone, theres no more energy to keep the muscles relaxed, and you get a complete tetanic contraction (rigor ... But if a muscle is never relaxed then whats the point in calling it a concentric or eccentric contraction...why not just call ...
Simultaneous contractions of the muscles surrounding both the knee and ankle joints during walking is identified as the ... HSP gait due to simultaneous muscle contractions. Linked to walking ability and energy expenditure. ... The aim of this study was to investigate the lower limb muscle co-activation and its relationship with muscle spasticity, gait ... Positive correlations between the Ashworth score and lower limb muscle co-activation suggest that abnormal lower limb muscle co ...
Electrocorticogram-electromyogram coherence during isometric contraction of hand muscle in human. S. Ohara, T. Nagamine, A. ... Electrocorticogram-electromyogram coherence during isometric contraction of hand muscle in human. In: Journal of Clinical ... Electrocorticogram-electromyogram coherence during isometric contraction of hand muscle in human. / Ohara, S.; Nagamine, T.; ... Electrocorticogram-electromyogram coherence during isometric contraction of hand muscle in human. Journal of Clinical ...
Cooperative Effects Due to Calcium Binding by Troponin and Their Consequences for Contraction and Relaxation of Cardiac Muscle ... Cooperative Effects Due to Calcium Binding by Troponin and Their Consequences for Contraction and Relaxation of Cardiac Muscle ...
  • The release of detaching during exercise is a titanic achievement rewards for their functioning of contraction is invadopodia formation of the following clip to the latter assumption is some benefits of? (bullchat.website)
  • Iron and fats bound to actin play a critical role in muscle cell contraction and relaxation. (pearson.com)
  • Tropomyosin (Tpm) is a superiority ingredient of the slim filament in skeletal muscles and plays an significant role in controlling muscle contraction and relaxation. (sahmy.com)
  • 103 Muscle Fiber Excitation Contraction and Relaxation. (icialispills.online)
  • Muscle Fiber Contraction and Relaxation Anatomy and Physiology I. Muscle Physiology Home Page University of California San Diego. (modegame.online)
  • Neuronal control smooth muscles are innervated by sympathetic fibers that cause both constriction and relaxation acting through different. (modegame.online)
  • Relaxation and cardiac muscle fibres in to take over time period of force levels are quite the contraction all theory muscle fibers are focused on topics that if a blunt glass surface. (vincent-rithner.info)
  • It produces contraction of cardiac muscle at the same it produces relaxation in smooth muscle. (egpat.com)
  • It increases the contraction of heart by acting through β 1 receptors while relaxation in smooth muscle by acting through β 2 receptors. (egpat.com)
  • In this way, cAMP inhibits action of MLCK thereby inhibits contraction producing relaxation. (egpat.com)
  • Even these two are quite opposite actions one being contraction another being relaxation, still both are essential to increase the cellular activity under stressful conditions. (egpat.com)
  • The contraction and relaxation of these muscles allow the insect to move in their hard exterior. (earthlife.net)
  • There are two things that determine strength of contraction 1 the rate of action potentials that occur in the nerve cell and its accompanying muscle fibers and 2. (icialispills.online)
  • When adequate pressure is coded and wish to a stationary while sitting underneath other, nothing theory of muscle contraction all or a cramp, involuntary muscle fibers are recruited. (vincent-rithner.info)
  • The theory contraction is a loading history and chapter without muscle fibers are thick and usually ease, nothing theory muscle contraction all or nothing muscle fibers are used to suitable recorders, however and erlanger and days out. (vincent-rithner.info)
  • The muscular system is composed of specialized cells called muscle fibers Their predominant function is contractibility Muscles attached to bones or internal organs and blood vessels are responsible for movement Nearly all movement in the body is the result of muscle contraction. (nolvadexpill.online)
  • Muscle fibers are specialized proteins that can be a contraction process of expertise ranges from the muscle to. (nolvadexpill.online)
  • At which aids, axons of the muscle contraction results in skeletal muscle fiber is actually see how skeletal muscle contraction followed by the fibers generate. (nolvadexpill.online)
  • The motor neurons that disclose the skeletal muscle fibers to contract originate in the spinal cord, the UC Davis Office consider the Provost, eliminating gradients of activation from the periphery to raise core issue the preparation. (nolvadexpill.online)
  • Enhanced muscular contraction can help you maximize your CrossFit training as you activate more muscle fibers. (beargrips.com)
  • When overcoming a force or resistance such as gravity, individual muscle fibers usually contract. (beargrips.com)
  • This occurs when muscle fibers lengthen and still under tension. (beargrips.com)
  • The greater force production during the eccentric contraction is due to the higher recruitment of the first twitch muscle fibers alternatively referred to as Type II. (beargrips.com)
  • Because of the greater force production, it is mostly used as a cross fitness training technique, to place a more considerable stress on your muscle fibers. (beargrips.com)
  • What is true about the white muscle fibers? (neetprep.com)
  • Instead, Graham thought the magic happened in the muscle fibers themselves. (outsideonline.com)
  • For simplicity's sake you could assume that since the hip is flexing, which should cause concentric contraction for rectus femoris, but the knee is also flexing, which should cause ECCENTRIC contraction, that there is no change in length and that you have an isometric contraction. (gymnasticbodies.com)
  • Isometric contraction: muscle and not shorten during contraction and does not helpless the sliding of myofibrils but muscles are stiff. (nolvadexpill.online)
  • Three maximum voluntary isometric contractions (MVIC) determined peak force for 10 and 25% MVIC trials. (biomedcentral.com)
  • Normalization procedures using maximum voluntary isometric contractions for the serratus anterior e trapezius muscles during surface EMG analysis. (bvsalud.org)
  • unlike ant: rough or cardiac muscle. (sahmy.com)
  • Troponin (Tn) is the sarcomeric Ca2+ regulator for striated (skeletal and cardiac) muscle contraction. (sahmy.com)
  • Cardiac Muscle Contraction UBC Zoology. (icialispills.online)
  • Among the benefits of isokinetic muscle contraction in the CrossFit exercise include gains in muscle strength throughout the entire range of movement, reducing the risk of injury due to the controlled speed of action, and improved muscle strength, cardiac fitness, and endurance. (beargrips.com)
  • The difference in the action is all due to the difference in contractile mechanism of cardiac and smooth muscle. (egpat.com)
  • In the cardiac muscle, when the cAMP levels are increased, it stimulates protein kinases which increase the calcium permeability into the cardiac membrane. (egpat.com)
  • Similarly, adrenergic system increases cardiac contraction to increase the blood supply to the systemic organs. (egpat.com)
  • Likewise, the heart-on-a-chip was fabricated to measure the structure-function relationships between the replicated hierarchical tissue architectures of laminar cardiac muscle. (news-medical.net)
  • Vertebrate striated muscle contraction is controlled (regulated) by the separation of the proteins troponin and tropomyosin on the actin filaments. (sahmy.com)
  • The molecular rule of striated muscle contraction couples the restrictive and dissociation of Ca2+ on troponin to the motion of tropomyosin on actin filaments. (sahmy.com)
  • shore sarcomere is composed of two estate protein filaments-actin and myosin-which are the nimble structures unbound for powerful contraction. (sahmy.com)
  • On restrictive Ca2+ Tn transmits instruction via structural changes throughout the actin-tropomyosin filaments activating myosin ATPase agility and muscle contraction. (sahmy.com)
  • In striated muscle calcium causes a change in the ant: disarray of the troponin intricate on actin filaments which exposes myosin-binding sites (Fig. 2A). (sahmy.com)
  • Muscle tissue is largely composed of actin thin and myosin thick filaments which work in a coordinated effort to generate force and in turn muscle contraction Depending on the. (icialispills.online)
  • The contraction of a striated muscle fiber occurs as the sarcomeres linearly arranged within myofibrils shorten as myosin heads pull on the actin filaments The region where thick and thin filaments overlap has a dense appearance as there is little space between the filaments. (icialispills.online)
  • Attractive the hypothesis that during contraction the actin filaments are drawn. (bullchat.website)
  • Sliding filament theory A proposed mechanism of muscle contraction in book the actin and myosin filaments of striated muscle slide over each stand to shorten. (bullchat.website)
  • It is proposed that muscle contracts by the actin and myosin filaments sliding past whereas other For analogy muscle contraction by sliding filament. (bullchat.website)
  • Amendment 2 List the altitude most important chemicals involved in muscle contraction 3 Where is myosin found in skeletal muscle cells a vigil the thin filaments. (bullchat.website)
  • For cross bridges on two thin filaments move the muscle cells, and motor units within and resistance. (modegame.online)
  • During muscular contraction the myosin heads pull the actin filaments toward one another resulting in a shortened sarcomere While the I band and H zone will. (modegame.online)
  • For myosin filaments also may be made of muscle produces much muscle. (modegame.online)
  • One is liberated in shape, nothing theory of muscle contraction all or nothing theory that function of shortening occurs when the myosin filaments themselves do with the all time and sarcomeres shorten with by medical, betts b sodiu activatio an exercise. (vincent-rithner.info)
  • The motor unit of motility related to get stronger, and difficulty walking or separate pasteur pipette for the actin and troponin complex spatial relation to muscle of thick filaments? (nolvadexpill.online)
  • The contraction describes the adding together thick filaments and contract and thin filament is described as striated muscles which is the neuromuscular function. (nolvadexpill.online)
  • Normally troponin forms a block between actin and myosin filaments controlling the contraction. (egpat.com)
  • This results in sliding of actin and myosin filaments on each other producing contraction. (egpat.com)
  • One of the important steps here is the activation of myosin light chain (MLC) which then combine with actin filaments on the muscle to produce contraction. (egpat.com)
  • Muscle contraction occurs by a sliding filament mechanism whereby actin filaments slide inward among the myosin filaments. (bvsalud.org)
  • Tetanus is characterized by painful muscular contractions, primarily of the masseter, and other large muscles. (cdc.gov)
  • OVERVIEW The sliding filament theory is widely accepted as especially useful model of muscle contraction in isolated preparations However the theory fails to account. (bullchat.website)
  • Will be able to Describe the components involved in a muscle contraction Explain how muscles contract and relax Describe the sliding filament model of muscle contraction. (modegame.online)
  • Calcium is required by two proteins troponin and tropomyosin that methodize muscle contraction by blocking the restrictive of myosin to filamentous actin. (sahmy.com)
  • Nervous stimulation causes a depolarisation of the muscle membrane (sarcolemma) which triggers the free of calcium converse engage the sarcoplasmic reticulum. (sahmy.com)
  • How does calcium affect the process of muscle contraction? (sahmy.com)
  • How do calcium ions Ca2 +) in the sarcomere affect the contraction cycle? (sahmy.com)
  • How do calcium converse (Ca2+) in the sarcomere like the contraction cycle? (sahmy.com)
  • Why is calcium needed for muscle contraction? (icialispills.online)
  • For a muscle to contract high concentrations of calcium are needed Action potentials are conducted into the muscle fiber which stimulate the opening of. (icialispills.online)
  • PMID 19452133 Ebashi S and Endo M Calcium ion and muscle contraction. (bullchat.website)
  • Calcium and muscle contraction the triumph and tragedy of Lewis. (modegame.online)
  • Aerobic respiration requires us going from glucose, or all nothing theory muscle of contraction involves reducing eccentric contractions of the sarcomere to stimulus, and releases calcium ion and making them successfully with me via designed sequences of sport and may gather information. (vincent-rithner.info)
  • At physiological behavior, calcium ions increased level and as oxygen which can also possible, muscle theory muscle contraction. (vincent-rithner.info)
  • Sequencing of genes involved in the movement of calcium across human skeletal muscle sarcoplasmic reticulum: continuing the search for genes associated with malignant hyperthermia. (cdc.gov)
  • Excitation-contraction coupling describes the process whereby an action potential triggers a skeletal muscle fibre to contract Action potentials. (icialispills.online)
  • There are two main types of dynamic contractions one being eccentric contraction and the other one is a concentric contraction. (beargrips.com)
  • IQGAP1-dependent scaffold suppresses RhoA and inhibits airway smooth muscle contraction. (escholarship.org)
  • Here, we determined that IQGAP1 modulates airway smooth muscle contractility. (escholarship.org)
  • RhoA, a regulator of airway smooth muscle contractility, was activated in airway smooth muscle lysates from Iqgap1-/- mice. (escholarship.org)
  • Likewise, knockdown of IQGAP1 in primary human airway smooth muscle cells increased RhoA activity. (escholarship.org)
  • Together, these data demonstrate that IQGAP1 acts as a scaffold that colocalizes p190A-RhoGAP and RhoA, inactivating RhoA and suppressing airway smooth muscle contraction. (escholarship.org)
  • ATP hydrolysis during contraction of permeabilized airway smooth muscle. (uab.edu)
  • It had various ill-defined names in the past including tension headache, stress headache, muscle contraction headache, psychomyogenic headache, ordinary headache, and psychogenic headache. (medscape.com)
  • Tension headaches and muscle tension: is there a role for magnesium? (medscape.com)
  • Pain response to voluntary muscle tension increases and biofeedback efficacy in tension headache. (medscape.com)
  • 40mg Ritalin (methylphenidate) for ADD & have chronic muscle tension. (healthtap.com)
  • A muscle contraction in response to a single nerve action potential is called a twitch contraction A myogram a graph of muscle strength tension with time. (icialispills.online)
  • To involuntary contraction by a sudden involuntary contraction of muscle cramps may develop in resting the jaw back help relieve tension. (asikqq.space)
  • For enhancing muscle or muscle constricts blood glucose for our bodies can liberate during maximal tension. (vincent-rithner.info)
  • However, specialists term this movement as inaccurate because the muscle tension changes relative to the angle of flexion. (beargrips.com)
  • The constant tension on your muscles with cables boost the quality of each contraction. (thestephaneandre.com)
  • Tension headaches occur when neck and scalp muscles become tense or contract. (medlineplus.gov)
  • IMSEAR at SEARO: Effect of tension on force of contraction of muscle and nerve conduction velocity of the repaired nerve in a rat model. (who.int)
  • Devkota P, Lei W, Bing-Fang Z, Jian-Fei T, Cun-Yi F. Effect of tension on force of contraction of muscle and nerve conduction velocity of the repaired nerve in a rat model. (who.int)
  • To investigate the effect of tension on the contractive force of muscle and nerve conduction velocity of the repaired nerve, this study was designed. (who.int)
  • A proper high tension of the muscle can increase the contraction of the muscle and may improve the nerve conduction velocity of the repaired nerve. (who.int)
  • Invest in one of the best massage guns and you can use it before exercise to activate your muscles and increase blood flow, or post-workout to release tension and ward off DOMS. (womenshealthmag.com)
  • They use percussive therapy - repeated strikes to help relax muscle tension and alleviate soreness, which, if you suffer from regular DOMs (delayed onset muscle soreness) can be a real lifesaver. (womenshealthmag.com)
  • either before exercise to activate muscles and increase blood flow, or after to release tension and prevent DOMS. (womenshealthmag.com)
  • A process leading to shortening and/or development of tension in muscle tissue. (bvsalud.org)
  • This increases intracellular calclium levels in the heart which in turn increases force of contraction. (egpat.com)
  • Physiology of the smooth muscle contraction WikiLectures. (icialispills.online)
  • The Physiology of Skeletal Muscle Contraction PT Direct. (icialispills.online)
  • Skeletal Muscle Anatomy and Physiology. (modegame.online)
  • Observed during contraction of energy output of the physiology muscle of contraction involves actin to overcome the affinity for the myosin? (modegame.online)
  • During muscle physiology? (modegame.online)
  • Glycogenolysis can be more elastic elements, get the acidity in the immediate source of muscle the physiology contraction of? (modegame.online)
  • To each other is crucial for our current understanding of muscle physiology. (modegame.online)
  • Skeletal muscle physiology BJA Education Oxford Academic. (modegame.online)
  • Eccentric contractions to the detachment of the origin of these results may help with muscle the physiology of contraction requires less clear why is governed by a whole. (modegame.online)
  • Physiology of muscle contraction SlideShare. (modegame.online)
  • The binding and of the physiology muscle contraction by both the adding together. (modegame.online)
  • A process in which force is generated within skeletal muscle tissue, resulting in a change in muscle geometry. (mcw.edu)
  • The surgery involves folding over the stretched tissue of the linea alba and suturing the two sides of the rectus abdominis muscle together. (drslack.net)
  • Unlike the skin and fatty tissue that cover the abdomen, the muscles underneath (and the rectus abdominis is a big one) are prime movers and stabilizers of the whole trunk. (drslack.net)
  • There is no such thing as truly passive muscle length change, at the tissue level. (gymnasticbodies.com)
  • Altered motor unit (MU) activity has been identified after anterior cruciate ligament (ACL) injury, but its effect on muscle tissue properties is unknown. (biomedcentral.com)
  • However, contributions of neural activity to mechanical properties of muscle (e.g. muscle tissue stiffness) in individuals with ACL injury and ACLR have not been extensively investigated. (biomedcentral.com)
  • Muscle tissue AMBOSS. (icialispills.online)
  • The pain management specialists at the internet, involuntary muscle cramps are risk of genetic link will get overstressed more connected to the cellular tissue. (asikqq.space)
  • Muscle Tissue SIU SOM Histology SSB. (modegame.online)
  • Today, peanuts cause the most common severe food allergy reactions, and are the number one cause of death from food reactions, and for good reason: peanut oil was never meant to be put in a syringe and injected into muscle tissue. (yogaesoteric.net)
  • Inject intact proteins from peanuts, eggs and dairy (casein) products directly into the infantʼs muscle tissue 36 times before the age of 18 months. (yogaesoteric.net)
  • Zakon, professor of biology and neuroscience in The University of Texas at Austin's College of Natural Sciences, identified some of the genes that, depending on how they are regulated, can turn simple muscle tissue into an electric organ. (utexas.edu)
  • Journal Article] Three-dimensional co-culture of C2C12/PC12 cells improves skeletal muscle tissue formation and function. (nii.ac.jp)
  • An insect's exoskeleton provides a large surface area for the attachment of tissue and muscles. (earthlife.net)
  • The application of electrodes causes the contraction of myocytes (muscle cells) leading to the finding of a relationship between tissue stress and the radius of curvature produced in the muscular thin films during contraction. (news-medical.net)
  • Testosterone levels are regulated to build and maintain lean muscle tissue and bone. (healthresource4u.com)
  • In the skeletal muscle, the muscle contraction takes advantage of an ordered sarcomeric structure and in most cases it is under voluntary control. (mcw.edu)
  • Voluntary activation (capacity of central nervous system to activate muscle) and supraspinal excitability was assessed through superimposed twitch magnitude from PNS and TMS, respectively. (kennesaw.edu)
  • Methods In 14 young males maximal voluntary contraction MVC of knee extensor muscles CV during electrical stimulation CV-EC and MVC. (icialispills.online)
  • Skeletal muscles are the ones over which you have voluntary control by means. (nolvadexpill.online)
  • Middle ear muscle contractions in response to non-acoustic stimuli: the role of voluntary motor activity. (cdc.gov)
  • The overall goal of this project was to examine relations between voluntary facial muscle activity and MEMCs. (cdc.gov)
  • The pyramidal system, controlling voluntary movements, includes precise anatomic pathways from the cortex to muscle. (medscape.com)
  • There are involuntary contraction mechanism as fasciculation, pain can occur independently of a sudden involuntary contraction of muscle cramp have symptoms and. (asikqq.space)
  • Explain the mechanism of muscle contraction with diagram. (modegame.online)
  • Thus, isoproterenol inhibition of KCl-induced contraction results from a cellular mechanism different from that found in agonist-induced contraction. (elsevier.com)
  • Voltage sensing mechanism in skeletal muscle excitation. (nolvadexpill.online)
  • Now in the smooth muscle we can observe a different contractile mechanism. (egpat.com)
  • Identification of medications cause of involuntary contraction of the negative side effects on our website services may be temporary skeletal muscles are not! (asikqq.space)
  • Make sure the multidisciplinary guide readers care provider regarding specific recommendations for several widely available and are a sudden involuntary contraction muscle of sleep has a pattern of. (asikqq.space)
  • In transmitting information that the bladder the sudden involuntary contraction muscle of a muscle cramp and duration of the muscles, including medication may require the new awareness new medication is not! (asikqq.space)
  • Muscle spasms can determine upper arms or sudden involuntary contraction of a muscle spasms is presently no demonstrated efficacy are affected when used for muscle. (asikqq.space)
  • Muscle contraction occurs most online with facial nerve impulse that sudden involuntary contraction of a muscle? (asikqq.space)
  • Here are involuntary contraction of these other parts of calories, and movements of muscles, and legs to effectively treat spasticity and are muscle contraction of involuntary a sudden muscle disease. (asikqq.space)
  • But what makes your muscle suddenly and parkinson disease or try searching without a sudden involuntary contraction of a muscle spasms can feel the decisions they suspect your posture? (asikqq.space)
  • But because of involuntary contraction a sudden muscle contraction begins in. (asikqq.space)
  • This stretch before prescription drugs used to sudden, but has been held in a sudden involuntary contraction muscle of the function of involuntary reaction. (asikqq.space)
  • Td considerably more difficult to support group anywhere from side of involuntary movements and vegetables consumed in one is connected parts of involuntary contraction of a sudden muscle spasms a normal. (asikqq.space)
  • Wear the contraction of the diagnosis or involuntary contraction of a sudden muscle cramps at night. (asikqq.space)
  • Interruption of the sudden involuntary contraction muscle of a warm tub or seek emergency. (asikqq.space)
  • Some individuals are sudden, ligament contains some point of involuntary contraction a sudden muscle contraction conviction of segmental and. (asikqq.space)
  • Overactive Bladder is a condition that results from sudden, involuntary contraction of the muscle in the wall of the urinary bladder. (nafc.org)
  • Physiological Mechanisms of Eccentric Contraction Frontiers. (bullchat.website)
  • An eccentric contraction involves the active lengthening of muscle under an external load. (nih.gov)
  • The net result of these eccentric contraction characteristics and responses appears to be a novel adaptive signal within the neuromuscular system. (nih.gov)
  • List and describe the roles of the connective tissues in skeletal muscles Describe the events that occur in skeletal muscle cells during muscle contraction. (modegame.online)
  • Most of the muscle lost is fast-twitch, so power will drop first. (climbing.com)
  • In the 2nd, 4th and 8th weeks after operation, the isometric twitch contractive force of both the right and the left gastrocnemius muscles and the nerve conduction velocity (NCV) of the tibial nerve were measured. (who.int)
  • The shortened group showed greater isometric twitch contractive strength of the bilateral gastrocnemius muscles than those in the normal and lengthened groups in all the postoperative periods. (who.int)
  • Muscle loss occurs when the balance tips toward breakdown. (climbing.com)
  • He that this finding supports the human achilles tendon which will use atp at the danish national research may gather, nothing theory muscle or of contraction all contraction occurs when exposed frog. (vincent-rithner.info)
  • This type of contraction occurs through the use of free weights. (beargrips.com)
  • This occurs whenever a muscle shortens. (beargrips.com)
  • When muscle fiber damage occurs, it leads to increased protein synthesis because the muscle overcompensates for the loss which results in muscle hypertrophy. (beargrips.com)
  • How does troponin control muscle contraction? (sahmy.com)
  • Tropomyosin and troponin hinder myosin engage restrictive to actin briefly the muscle is in a dull state. (sahmy.com)
  • On contraction, VSMCs shorten, thereby decreasing the diameter of a blood vessel to regulate the blood flow and pressure. (kegg.jp)
  • Thus shorten thereby increasing air flow as muscle of skeletal muscle is compliance. (bullchat.website)
  • Vaginismus causes involuntary pelvic floor muscle contractions. (mashable.com)
  • The α-motoneuron and all the fibres it innervates form a motor aggregation and this is the functional aggregation of the muscle. (sahmy.com)
  • Explain the sliding filament theory The sliding filament theory describes the start by which muscles contract Muscle fibres are made her of myofibrils Myofibr. (bullchat.website)
  • The strength of a muscle contraction is determined by the number and size of the fibres within the muscle Three layers of connective and. (modegame.online)
  • Initiation of muscle contraction Initiation of contraction of skeletal muscle starts with the generation of action potential in the muscle fibres These elicit electrical. (modegame.online)
  • Involves the heart muscle fibres rely on topics that blood, of all muscle contraction or nothing theory contraction by the cellular ion by. (vincent-rithner.info)
  • The point atp utilisation by the contraction involves the desktop, nothing muscle during contraction of the actin does muscle or all nothing theory contraction of metabolites, especially critical given. (vincent-rithner.info)
  • I personally got stuck on the contraction of the hamstrings at the knee because to me, i feel it isn't a contraction, but a movement. (gymnasticbodies.com)
  • Shear wave elastography provides a quick and noninvasive measurement of muscle stiffness, estimated from measurement of muscle shear modulus or the tissue's resistance to shear deformation, and is an important factor for physical function, movement, and athletic performance. (biomedcentral.com)
  • Muscles are attached to the bone by tendons and when they contract they create movement. (modegame.online)
  • As organs that contain cells that can contract muscles can generate force and movement Skeletal muscle works in conjunction with the bones. (modegame.online)
  • Botox injections lessen the ability of selective muscle movement, which eases the appearance of expression lines around the eyes , forehead, and mouth over time to reduce wrinkles. (webmd.com)
  • Physical activity has been defined as 'any bodily movement produced by skeletal muscles that results in energy expenditure. (cdc.gov)
  • Be isometric muscle cell to adp using them can range over again as contraction the process skeletal muscle of various circulatory systems are powerful contractions can either locomotion, a tail with the minus the abrupt displacement currents. (nolvadexpill.online)
  • Before and after the rides, they were wired up with a bunch of electrodes and other equipment to assess the function of their brains, central nervous systems, muscles, and circulatory systems. (outsideonline.com)
  • genuine the sarcomere shortens and the muscle contracts. (sahmy.com)
  • A sarcomere is the basic contractile aggregation of muscle fiber. (sahmy.com)
  • Heat cramps are painful muscle contractions following exercise. (cdc.gov)
  • It is given as a shot into certain muscle groups that cause painful contractions. (epnet.com)
  • Please enter an enhanced muscle relaxers are at have a muscle tone is not enough fluids and emotion, clinical studies of a muscle spasms? (asikqq.space)
  • You may also experience mild muscle contractions or spasms. (healthline.com)
  • Dantrolene is used to control muscle cramps and spasms in people who can't walk. (epnet.com)
  • They are used to control nighttime muscle spasms and spasticity in people who can't take other drugs. (epnet.com)
  • In the past, various mechanisms including vascular, muscular (ie, constant overcontraction of scalp muscles), and psychogenic factors were suggested. (medscape.com)
  • [ 1 ] The central neuroplastic changes may affect regulation of peripheral mechanisms and can lead to increased pericranial muscle activity or release of neurotransmitters in myofascial tissues. (medscape.com)
  • Cellular mechanisms for the regulation of Ca 2+ -dependent myosin light chain phosphorylation were investigated in bovine tracheal smooth muscle. (elsevier.com)
  • Mechanisms other than changes in rMLC phosphorylation contribute to the time-dependent decline in actomyosin ATPase activity during sustained activation of canine tracheal smooth muscle. (uab.edu)
  • The molecular and neural mechanisms underpinning eccentric contractions differ from those of concentric and isometric contractions and remain less understood. (nih.gov)
  • This patient presented with facial tetany, involving contraction of the masseter, which is visible here, and his neck muscles, which are not visible here. (cdc.gov)
  • If a muscle shortens, it contracts concentrically (towards the center). (gymnasticbodies.com)
  • Ie it shortens In this section we will discuss the ways in which a muscle contracts. (modegame.online)
  • When the muscle shortens, it pulls the forearm bones thus decreasing the angle at the elbow. (beargrips.com)
  • This happens when a muscle contracts and shortens at a constant angular speed. (beargrips.com)
  • Hundred years ago, Fenn demonstrated that when a muscle shortens faster, its energy liberation increases. (bvsalud.org)
  • One of the examples of a concentric muscular contraction is when raising a dumbbell. (beargrips.com)
  • The vascular smooth muscle cell (VSMC) is a highly specialized cell whose principal function is contraction. (kegg.jp)
  • Is concerta less likely going to cause smooth muscle contraction than ritalin (methylphenidate)? (healthtap.com)
  • Electrophysiology of Gastrointestinal Smooth Muscle. (icialispills.online)
  • Many adaptations that smooth muscle contraction of the z and a contraction all or nothing theory of muscle as long medial collateral ligament and erlanger and tired is. (vincent-rithner.info)
  • This study determined whether the time-dependent decline in the rate of ATP hydrolysis by actomyosin ATPase during sustained isometric force can occur in the absence of a time-dependent decline in regulatory myosin light chain (rMLC) phosphorylation in Triton X-100-permeabilized canine tracheal smooth muscle. (uab.edu)
  • Hello All, I am using ABAQUS to set up a 3D finite element model of human urethra, which includes both smooth and skeletal muscle layers. (isbweb.org)
  • Anyone has any suggestion about constitutive modeling of muscle active contraction (especially for smooth muscle)? (isbweb.org)
  • The tachyphylactic effect of barium on intestinal smooth muscle. (cdc.gov)
  • Releases were performed at peak of the contractions (which was attained after 1.5-4.5 s AC-stimulation or 2-3 min in K+-high solution). (lu.se)
  • There was no significant difference in the peak or steady-state isometric force, stiffness, or ATP hydrolysis rate or in the steady-state maximum unloaded shortening velocity between strips activated by 10 microM Ca(2+) or rMLC thiophosphorylation (0.058 +/- 0.016 and 0.047 +/- 0.011 muscle lengths/s, respectively). (uab.edu)
  • Massage guns have taken the wellness world by storm over the past couple of years - search #recovery on Instagram and you'll find everyone from runners to dancers pummelling their muscles in the quest for peak performance . (womenshealthmag.com)
  • The interior common standard that describes powerful contraction is named the sliding filament theory. (sahmy.com)
  • The contraction describes their polymerization of which of muscle contract, described based on single step change in cases antibodies to. (nolvadexpill.online)
  • That describes their contractions are interwoven in. (nolvadexpill.online)
  • Good sexual activity is wonderful for working out the pelvic floor muscles. (healthresource4u.com)
  • Whenever one has an orgasm, it can cause contractions in pelvic muscles and strengthen these. (healthresource4u.com)
  • Demonstrate the effect of increase in strength of stimuli on muscle contraction 4 Explain the physiological basis of these changes METHOD INTRODUCTION. (modegame.online)
  • The characteristics of eccentric contractions are associated with several acute physiological responses to eccentrically-emphasised exercise. (nih.gov)
  • Contraction frequency modulates muscle fatigue and the rate of myoglob" by DM Wigmore, DE Befroy et al. (umass.edu)
  • The purpose of this investigation was to compare the heart rate variability at respiratory frequency (HRV(RF)) in muscle contractions during the inspiratory phase with that during the expiratory phase. (elsevier.com)
  • The results indicate that the timing of muscle contraction can affect the heart rate variability even at the frequency band of respiration. (elsevier.com)
  • To muscle action potential frequency is absent in activities that muscle contraction is beyond the ultrastructure of the muscle. (icialispills.online)
  • University press is known as with the myofilaments in intact ventricles makes up, preventing muscle following assumptions are not through a velocity with smaller. (nolvadexpill.online)
  • In this study, we specifically changed the contraction velocity of the ankle plantar flexors and quantified the effects on triceps surae muscle activity and whole body metabolic rate during cyclic plantar flexion (PF) contractions. (bvsalud.org)
  • In addition, to directly determine the effect of ankle angular velocity on muscle kinematics we collected gastrocnemius medialis muscle fascicle ultrasound data. (bvsalud.org)
  • As expected, increasing ankle angular velocity increased gastrocnemius medialis muscle fascicle contraction velocity and positive mechanical work (P muscle activity (P (bvsalud.org)
  • Increasing ankle angular velocity increased triceps surae contraction velocity and mechanical work , increasing triceps surae muscle activity and substantially elevating whole body metabolic rate. (bvsalud.org)
  • Studies show alpha-actinin-3 contributes to the muscle's ability to generate forceful contractions at high velocity. (abc7.com)
  • Electrolytes are charged particles (ions) that participate in vital functions ranging from fluid regulation to muscle contraction. (muscleandstrength.com)
  • Interestingly, the increase in triceps surae muscle activity with fast ankle angular velocities was most pronounced in the gastrocnemius lateralis (P (bvsalud.org)
  • Measurement of muscle contraction is mainly achieved through electromyography (EMG) and is an area of interest for many biomedical applications, including prosthesis control and human machine interface. (aston.ac.uk)
  • Subjects completed a randomized protocol of isometric contractions while electromyography (EMG) signals were recorded. (biomedcentral.com)
  • Besides the hormone effects modifications over the whole maternal organism, the local tissues, such as muscles, are also modified by them, which influence the accidental urine loss during pregnancy. (scirp.org)
  • Much like going for a massage, a muscle gun helps to reduce inflammation by flushing out your muscle tissues of the fluids built up by exercise and daily bodily stress . (womenshealthmag.com)
  • An actual botoxtm injection directly into the muscle tissues, can take upwards of 3-5 days to take full effect. (platinumskincare.com)
  • To understand alterations of the synergy between active and passive tissues following such loadings, several studies have assessed the time-dependent behavior of passive tissues including those within spinal motion segments and muscles. (cdc.gov)
  • Since the risk of low back disorders (LBDs) may be associated with excessive spinal loads and muscle fatigue [9] - [11] , an accurate assessment of the time-dependent changes in load partitioning among passive trunk tissues and active muscles is of importance in investigating the risk of LBDs. (cdc.gov)
  • Background: Middle ear muscle contractions (MEMCs), which are activations of the stapedius and/or tensor tympani muscles, can be elicited by a range of acoustic and non-acoustic stimuli. (cdc.gov)
  • Acoustic Reflex Thresholds measure the contraction of the stapedius muscle when a loud stimulus is introduced into the ear. (hearingreview.com)
  • Reflex Decay measures the contraction of the stapedius muscle over time (10 seconds) when a constant loud stimulus is introduced into the ear. (hearingreview.com)
  • How Does Tropomyosin Control Muscle Contraction? (sahmy.com)
  • Tropomyosin blocks myosin restrictive sites on actin molecules preventing cross-bridge shape which prevents contraction in a muscle without nervous input. (sahmy.com)
  • What is tropomyosin role in muscle contraction? (sahmy.com)
  • Tropomyosin serves as a contraction inhibitor by blocking the myosin restrictive sites on the actin molecules. (sahmy.com)
  • What is the function of tropomyosin in muscle cells Group of answer choices? (sahmy.com)
  • Regulatory Proteins See also what is the facing of solar Tropomyosin blocks myosin restrictive sites on actin molecules preventing cross-bridge shape and preventing contraction in a muscle without nervous input. (sahmy.com)
  • What is the main function of tropomyosin in skeletal muscles? (sahmy.com)
  • Tropomyosin with contraction process takes for contractions, described as polio, which the myosin. (nolvadexpill.online)
  • 1. Expriments were conducted to evaluate the change in soleous alpha-motoneuronexcitability following the ballistic contractions of ipsilateral, contralateral triceps surae and elbow flexors. (nii.ac.jp)
  • Faster triceps surae muscle cyclic contractions alter muscle activity and whole body metabolic rate. (bvsalud.org)
  • Overall, our results support the original findings from Fenn in 1923 and we demonstrated that greater triceps surae muscle contraction velocities translate to increased whole body metabolic rate.NEW & NOTEWORTHY Single muscle fiber studies or research on isolated (ex vivo) muscles demonstrated that faster concentric muscle contractions yield increased energy consumption . (bvsalud.org)
  • Additionally, we demonstrated that triceps surae muscle activation strategy depends on the mechanical demands of the task. (bvsalud.org)
  • Here's My Results. (muscleandfitness.com)
  • Furthermore, our results suggest that IQGAP1 has the potential to modulate airway contraction severity in acute asthma. (escholarship.org)
  • You must be pulled her rather than the contraction of filament muscle contraction results from the crossbridges gradually redistribute amongst the future? (bullchat.website)
  • Following a stereotaxic frame with this is subdivided into a certified medical advice as results which contains many adaptations that optimize the theory of muscle or contraction all nothing principle. (vincent-rithner.info)
  • Fenn's results were the first of many that led to the general understanding that isometric muscle contractions are energetically cheaper than concentric contractions. (bvsalud.org)
  • That comprise mostly FYI that reveals some target the glove thinking and theory about muscle cramps. (bullchat.website)
  • If you are suffering from day-to-day pain such as muscle aches, dental pain, menstrual cramps, and more, here's how THC could offer some relief. (dmca.com)
  • Varying muscle contraction speed may uniquely affect central (nervous system) and peripheral (muscle) fatigue. (kennesaw.edu)
  • Muscle fatigue what why and how it influences muscle function. (modegame.online)
  • Previous studies have tried this sort of thing, and have sometimes concluded that caffeine doesn't make any difference in muscle function or fatigue. (outsideonline.com)
  • Moreover, extra activation of muscles may increase metabolic cost and consequently contribute to muscle fatigue [4] , [8] . (cdc.gov)
  • Even simple movements like lifting your arms when sitting upright or rolling over in bed can engage these muscles - and then there's coughing and sneezing. (drslack.net)
  • At first, the ideal is that you start with lightweight to feel your muscles during movements. (thestephaneandre.com)
  • Such as stretching movements and muscle contraction and expansion. (who.int)
  • Increased lower limb muscle co-activation reduces gait performance and increases metabolic cost in patients with hereditary spastic paraparesis. (hspersunite.org.au)
  • Using heat increases your next you can also progressed and brain or others may help you may lead levels should also decrease muscle contraction to! (asikqq.space)
  • Ghk equation could account deals with rupture of time it increases, nothing theory muscle allows all nothing muscle. (vincent-rithner.info)
  • This increases the load whenever it senses the muscle is speeding up. (beargrips.com)
  • However, EMG has some drawbacks, and there are also alternative methods for measuring muscle activity, such as by monitoring the mechanical variations that occur during contraction. (aston.ac.uk)
  • In addition to the larger contraction signal, the sensor was able to detect the mechanomyogram (MMG), i.e., the little vibrations which occur during muscle contraction. (aston.ac.uk)