Adrenergic Fibers: Nerve fibers liberating catecholamines at a synapse after an impulse.Nerve Fibers: Slender processes of NEURONS, including the AXONS and their glial envelopes (MYELIN SHEATH). Nerve fibers conduct nerve impulses to and from the CENTRAL NERVOUS SYSTEM.Superior Cervical Ganglion: The largest and uppermost of the paravertebral sympathetic ganglia.Helium: Helium. A noble gas with the atomic symbol He, atomic number 2, and atomic weight 4.003. It is a colorless, odorless, tasteless gas that is not combustible and does not support combustion. It was first detected in the sun and is now obtained from natural gas. Medically it is used as a diluent for other gases, being especially useful with oxygen in the treatment of certain cases of respiratory obstruction, and as a vehicle for general anesthetics. (Dorland, 27th ed)Ganglia, Sympathetic: Ganglia of the sympathetic nervous system including the paravertebral and the prevertebral ganglia. Among these are the sympathetic chain ganglia, the superior, middle, and inferior cervical ganglia, and the aorticorenal, celiac, and stellate ganglia.Ganglia, Autonomic: Clusters of neurons and their processes in the autonomic nervous system. In the autonomic ganglia, the preganglionic fibers from the central nervous system synapse onto the neurons whose axons are the postganglionic fibers innervating target organs. The ganglia also contain intrinsic neurons and supporting cells and preganglionic fibers passing through to other ganglia.Urethane: Antineoplastic agent that is also used as a veterinary anesthetic. It has also been used as an intermediate in organic synthesis. Urethane is suspected to be a carcinogen.Neurons: The basic cellular units of nervous tissue. Each neuron consists of a body, an axon, and dendrites. Their purpose is to receive, conduct, and transmit impulses in the NERVOUS SYSTEM.Cell Nucleolus: Within most types of eukaryotic CELL NUCLEUS, a distinct region, not delimited by a membrane, in which some species of rRNA (RNA, RIBOSOMAL) are synthesized and assembled into ribonucleoprotein subunits of ribosomes. In the nucleolus rRNA is transcribed from a nucleolar organizer, i.e., a group of tandemly repeated chromosomal genes which encode rRNA and which are transcribed by RNA polymerase I. (Singleton & Sainsbury, Dictionary of Microbiology & Molecular Biology, 2d ed)Complex Regional Pain Syndromes: Conditions characterized by pain involving an extremity or other body region, HYPERESTHESIA, and localized autonomic dysfunction following injury to soft tissue or nerve. The pain is usually associated with ERYTHEMA; SKIN TEMPERATURE changes, abnormal sudomotor activity (i.e., changes in sweating due to altered sympathetic innervation) or edema. The degree of pain and other manifestations is out of proportion to that expected from the inciting event. Two subtypes of this condition have been described: type I; (REFLEX SYMPATHETIC DYSTROPHY) and type II; (CAUSALGIA). (From Pain 1995 Oct;63(1):127-33)Reflex Sympathetic Dystrophy: A syndrome characterized by severe burning pain in an extremity accompanied by sudomotor, vasomotor, and trophic changes in bone without an associated specific nerve injury. This condition is most often precipitated by trauma to soft tissue or nerve complexes. The skin over the affected region is usually erythematous and demonstrates hypersensitivity to tactile stimuli and erythema. (Adams et al., Principles of Neurology, 6th ed, p1360; Pain 1995 Oct;63(1):127-33)Periodicals as Topic: A publication issued at stated, more or less regular, intervals.Phenoxybenzamine: An alpha-adrenergic antagonist with long duration of action. It has been used to treat hypertension and as a peripheral vasodilator.Anesthesiology: A specialty concerned with the study of anesthetics and anesthesia.Causalgia: A complex regional pain syndrome characterized by burning pain and marked sensitivity to touch (HYPERESTHESIA) in the distribution of an injured peripheral nerve. Autonomic dysfunction in the form of sudomotor (i.e., sympathetic innervation to sweat glands), vasomotor, and trophic skin changes may also occur. (Adams et al., Principles of Neurology, 6th ed, p1359)Access to Information: Individual's rights to obtain and use information collected or generated by others.Mesenteric Artery, Inferior: The artery supplying nearly all the left half of the transverse colon, the whole of the descending colon, the sigmoid colon, and the greater part of the rectum. It is smaller than the superior mesenteric artery (MESENTERIC ARTERY, SUPERIOR) and arises from the aorta above its bifurcation into the common iliac arteries.Mesenteric Artery, Superior: A large vessel supplying the whole length of the small intestine except the superior part of the duodenum. It also supplies the cecum and the ascending part of the colon and about half the transverse part of the colon. It arises from the anterior surface of the aorta below the celiac artery at the level of the first lumbar vertebra.Basal Ganglia: Large subcortical nuclear masses derived from the telencephalon and located in the basal regions of the cerebral hemispheres.Autonomic Nervous System: The ENTERIC NERVOUS SYSTEM; PARASYMPATHETIC NERVOUS SYSTEM; and SYMPATHETIC NERVOUS SYSTEM taken together. Generally speaking, the autonomic nervous system regulates the internal environment during both peaceful activity and physical or emotional stress. Autonomic activity is controlled and integrated by the CENTRAL NERVOUS SYSTEM, especially the HYPOTHALAMUS and the SOLITARY NUCLEUS, which receive information relayed from VISCERAL AFFERENTS.Mesenteric Arteries: Arteries which arise from the abdominal aorta and distribute to most of the intestines.Microglia: The third type of glial cell, along with astrocytes and oligodendrocytes (which together form the macroglia). Microglia vary in appearance depending on developmental stage, functional state, and anatomical location; subtype terms include ramified, perivascular, ameboid, resting, and activated. Microglia clearly are capable of phagocytosis and play an important role in a wide spectrum of neuropathologies. They have also been suggested to act in several other roles including in secretion (e.g., of cytokines and neural growth factors), in immunological processing (e.g., antigen presentation), and in central nervous system development and remodeling.Synaptic Transmission: The communication from a NEURON to a target (neuron, muscle, or secretory cell) across a SYNAPSE. In chemical synaptic transmission, the presynaptic neuron releases a NEUROTRANSMITTER that diffuses across the synaptic cleft and binds to specific synaptic receptors, activating them. The activated receptors modulate specific ion channels and/or second-messenger systems in the postsynaptic cell. In electrical synaptic transmission, electrical signals are communicated as an ionic current flow across ELECTRICAL SYNAPSES.Excitatory Postsynaptic Potentials: Depolarization of membrane potentials at the SYNAPTIC MEMBRANES of target neurons during neurotransmission. Excitatory postsynaptic potentials can singly or in summation reach the trigger threshold for ACTION POTENTIALS.Glutamic Acid: A non-essential amino acid naturally occurring in the L-form. Glutamic acid is the most common excitatory neurotransmitter in the CENTRAL NERVOUS SYSTEM.Brain: The part of CENTRAL NERVOUS SYSTEM that is contained within the skull (CRANIUM). Arising from the NEURAL TUBE, the embryonic brain is comprised of three major parts including PROSENCEPHALON (the forebrain); MESENCEPHALON (the midbrain); and RHOMBENCEPHALON (the hindbrain). The developed brain consists of CEREBRUM; CEREBELLUM; and other structures in the BRAIN STEM.Rats, Sprague-Dawley: 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.Photons: Discrete concentrations of energy, apparently massless elementary particles, that move at the speed of light. They are the unit or quantum of electromagnetic radiation. Photons are emitted when electrons move from one energy state to another. (From Hawley's Condensed Chemical Dictionary, 11th ed)Spirogyra: A genus of filamentous algae in the order ZYGNEMATALES, family Zygnemataceae, named for the helical arrangement of its CHLOROPLASTS. It is commonly found in freshwater habitats.Lasers: An optical source that emits photons in a coherent beam. Light Amplification by Stimulated Emission of Radiation (LASER) is brought about using devices that transform light of varying frequencies into a single intense, nearly nondivergent beam of monochromatic radiation. Lasers operate in the infrared, visible, ultraviolet, or X-ray regions of the spectrum.Fluorescence Polarization: Measurement of the polarization of fluorescent light from solutions or microscopic specimens. It is used to provide information concerning molecular size, shape, and conformation, molecular anisotropy, electronic energy transfer, molecular interaction, including dye and coenzyme binding, and the antigen-antibody reaction.PhotochemistryMolecular Probes: A group of atoms or molecules attached to other molecules or cellular structures and used in studying the properties of these molecules and structures. Radioactive DNA or RNA sequences are used in MOLECULAR GENETICS to detect the presence of a complementary sequence by NUCLEIC ACID HYBRIDIZATION.Fluorescent Dyes: Agents that emit light after excitation by light. The wave length of the emitted light is usually longer than that of the incident light. Fluorochromes are substances that cause fluorescence in other substances, i.e., dyes used to mark or label other compounds with fluorescent tags.Microspheres: Small uniformly-sized spherical particles, of micrometer dimensions, frequently labeled with radioisotopes or various reagents acting as tags or markers.Latex: A milky, product excreted from the latex canals of a variety of plant species that contain cauotchouc. Latex is composed of 25-35% caoutchouc, 60-75% water, 2% protein, 2% resin, 1.5% sugar & 1% ash. RUBBER is made by the removal of water from latex.(From Concise Encyclopedia Biochemistry and Molecular Biology, 3rd ed). Hevein proteins are responsible for LATEX HYPERSENSITIVITY. Latexes are used as inert vehicles to carry antibodies or antigens in LATEX FIXATION TESTS.Gastric Fundus: The superior portion of the body of the stomach above the level of the cardiac notch.Esophagus: The muscular membranous segment between the PHARYNX and the STOMACH in the UPPER GASTROINTESTINAL TRACT.Esophageal Sphincter, Upper: The structure at the pharyngoesophageal junction consisting chiefly of the CRICOPHARYNGEUS MUSCLE. It normally occludes the lumen of the ESOPHAGUS, except during SWALLOWING.Stomach: 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.Rhodamines: A family of 3,6-di(substituted-amino)-9-benzoate derivatives of xanthene that are used as dyes and as indicators for various metals; also used as fluorescent tracers in histochemistry.Absenteeism: Chronic absence from work or other duty.Common Cold: A catarrhal disorder of the upper respiratory tract, which may be viral or a mixed infection. It generally involves a runny nose, nasal congestion, and sneezing.Communicable DiseasesSchools: Educational institutions.Biological Science Disciplines: All of the divisions of the natural sciences dealing with the various aspects of the phenomena of life and vital processes. The concept includes anatomy and physiology, biochemistry and biophysics, and the biology of animals, plants, and microorganisms. It should be differentiated from BIOLOGY, one of its subdivisions, concerned specifically with the origin and life processes of living organisms.Audiovisual Aids: Auditory and visual instructional materials.Computer-Assisted Instruction: A self-learning technique, usually online, involving interaction of the student with programmed instructional materials.Encyclopedias as Topic: Works containing information articles on subjects in every field of knowledge, usually arranged in alphabetical order, or a similar work limited to a special field or subject. (From The ALA Glossary of Library and Information Science, 1983)Antihypertensive Agents: Drugs used in the treatment of acute or chronic vascular HYPERTENSION regardless of pharmacological mechanism. Among the antihypertensive agents are DIURETICS; (especially DIURETICS, THIAZIDE); ADRENERGIC BETA-ANTAGONISTS; ADRENERGIC ALPHA-ANTAGONISTS; ANGIOTENSIN-CONVERTING ENZYME INHIBITORS; CALCIUM CHANNEL BLOCKERS; GANGLIONIC BLOCKERS; and VASODILATOR AGENTS.Hypertension: Persistently high systemic arterial BLOOD PRESSURE. Based on multiple readings (BLOOD PRESSURE DETERMINATION), hypertension is currently defined as when SYSTOLIC PRESSURE is consistently greater than 140 mm Hg or when DIASTOLIC PRESSURE is consistently 90 mm Hg or more.EncyclopediasBlood Pressure: PRESSURE of the BLOOD on the ARTERIES and other BLOOD VESSELS.Dictionaries, MedicalDictionaries as Topic: Lists of words, usually in alphabetical order, giving information about form, pronunciation, etymology, grammar, and meaning.

Activated macrophages and microglia induce dopaminergic sprouting in the injured striatum and express brain-derived neurotrophic factor and glial cell line-derived neurotrophic factor. (1/373)

Nigrostriatal dopaminergic neurons undergo sprouting around the margins of a striatal wound. The mechanism of this periwound sprouting has been unclear. In this study, we have examined the role played by the macrophage and microglial response that follows striatal injury. Macrophages and activated microglia quickly accumulate after injury and reach their greatest numbers in the first week. Subsequently, the number of both cell types declines rapidly in the first month and thereafter more slowly. Macrophage numbers eventually cease to decline, and a sizable group of these cells remains at the wound site and forms a long-term, highly activated resident population. This population of macrophages expresses increasing amounts of glial cell line-derived neurotrophic factor mRNA with time. Brain-derived neurotrophic factor mRNA is also expressed in and around the wound site. Production of this factor is by both activated microglia and, to a lesser extent, macrophages. The production of these potent dopaminergic neurotrophic factors occurs in a similar spatial distribution to sprouting dopaminergic fibers. Moreover, dopamine transporter-positive dopaminergic neurites can be seen growing toward and embracing hemosiderin-filled wound macrophages. The dopaminergic sprouting that accompanies striatal injury thus appears to result from neurotrophic factor secretion by activated macrophages and microglia at the wound site.  (+info)

Facilitatory beta2-adrenoceptors on cholinergic and adrenergic nerve endings of the guinea pig trachea. (2/373)

Using electrical field stimulation of epithelium-denuded intact guinea pig tracheal tube preparations, we studied the presence and role of prejunctional beta2-adrenoceptors by measuring evoked endogenous acetylcholine (ACh) and norepinephrine (NE) release directly. Analysis of ACh and NE was through two HPLC systems with electrochemical detection. Electrical field stimulation (150 mA, 0.8 ms, 16 Hz, 5 min, biphasic pulses) released 29.1 +/- 2.5 pmol ACh/g tissue and 70.2 +/- 6.2 pmol NE/g tissue. Preincubation for 15 min with the selective beta2-adrenoceptor agonist fenoterol (1 microM) increased both ACh and NE overflow to 178 +/- 28 (P < 0.01) and 165 +/- 12% (P < 0.01), respectively, of control values, increases that were abolished completely by the selective beta2-adrenoceptor antagonist ICI-118551 (1 microM). Further experiments with increasing fenoterol concentrations (0.1-100 microM) and different preincubation periods (1, 5, and 15 min) showed a strong and concentration-dependent facilitation of NE release, with maximum response levels decreasing (from nearly 5-fold to only 2.5-fold of control value) with increasing agonist contact time. In contrast, sensitivity of facilitatory beta2-adrenoceptors on cholinergic nerves to fenoterol gradually increased when the incubation period was prolonged; in addition, a bell-shaped concentration-response relationship was found at 15 min of preincubation. Fenoterol concentration-response relationships (15-min agonist preincubation) in the presence of atropine and yohimbine (1 microM each) were similar in the case of NE release, but in the case of ACh release, the bell shape was lost. The results indicate a differential capacity and response time profile of facilitatory prejunctional beta2-adrenoceptors on adrenergic and cholinergic nerve terminals in the guinea pig trachea and suggest that the receptors on adrenergic nerves are more susceptible to desensitization.  (+info)

Impact of development and chronic hypoxia on NE release from adrenergic nerves in sheep arteries. (3/373)

To examine effects of development and chronic high-altitude hypoxia on sympathetic nerve function in sheep, norepinephrine release was measured in vitro from middle cerebral and facial arteries. Capsaicin was used to test the role of capsaicin-sensitive sensory nerves; norepinephrine release was not altered by capsaicin treatment. Nomega-nitro-L-arginine methyl ester (L-NAME), an inhibitor of NO synthase, decreased stimulation-evoked norepinephrine release in middle cerebral arteries from normoxic sheep with no effect in hypoxic arteries or facial arteries. Thus NO-releasing nerves augmented norepinephrine release. Furthermore, the function of NO-releasing nerves declined after chronic hypoxia. Despite loss of the augmenting effects of NO, stimulation-evoked fractional norepinephrine release was unchanged after chronic hypoxia, suggesting that middle cerebral arteries adapt to hypoxia by increasing stimulation-evoked norepinephrine release. In fetal facial arteries, chronic hypoxia resulted in a decline in stimulation-evoked norepinephrine release, but there was an increase in the adult facial artery. In the adult, adaptation to chronic hypoxia is similar in both cerebral and facial arteries. However, differential adaptation in fetal adrenergic nerves may reflect differences in fetal redistribution of blood flow in the face of chronic hypoxia but could also possibly contribute to increased incidence of fetal morbidity.  (+info)

Estradiol modulates vascular response to melatonin in rat caudal artery. (4/373)

The purpose of this study was to determine whether estrogen modulates the function of vascular melatonin receptors. We used the rat caudal artery and found that the contractile effects of melatonin were influenced by the estrous cycle, ovariectomy, and estrogen replacement. In arterial ring segments isolated from female rats, melatonin potentiated, in a concentration-dependent manner, contractions produced either by adrenergic nerve stimulation or by phenylephrine. Constrictor responses to melatonin were smaller in arteries from female rats in proestrus compared with other stages of the estrous cycle and after ovariectomy. Administration of 17beta-estradiol to ovariectomized female rats also resulted in decreased constriction of isolated arteries to melatonin; however, in vitro addition of 17beta-estradiol (10(-7) M) had no effect. In the caudal artery, melatonin appears to act on two receptor subtypes that mediate contraction and relaxation, respectively. The selective melatonin MT2-receptor antagonist 4-phenyl-2-propionamidotetraline (4P-PDOT) enhanced constrictor responses to melatonin in arterial segments from intact female rats, consistent with the inhibition of MT2 receptor-mediated relaxation. In contrast, 4P-PDOT had no significant effect in arteries from ovariectomized female rats. However, when estradiol was replaced in vivo, the effect of 4P-PDOT on melatonin responses was restored. Thus circulating estradiol appears to enhance MT2 melatonin-receptor function in the thermoregulatory caudal artery of the female rat resulting in increased vasodilatation in response to melatonin.  (+info)

Adrenergic innervation in reactive human lymph nodes. (5/373)

Several experimental models have demonstrated that the central nervous system is functionally linked to the immune system by means of the autonomic nervous system. Samples of 36 lymph nodes of patients whose ages ranged from 16 to 69 y were studied. In order to demonstrate the existence and distribution of sympathetic nerve fibres, a polyclonal antibody antityrosine hydroxylase (TH), with the streptavidin-biotin system of detection, was used. TH-positive nerve fibres appeared in all reactive patterns of the lymph nodes studied. Thin nerve fascicles ramified at the hilar region and also in the connective tissue septae. Adventitial adrenergic nerve fibres were found following afferent, and to a lesser extent, efferent blood vessels. Another source of incoming nerve fibres was found at capsular level, accompanying blood vessels. On the arterial side, the innervation ceased before reaching the follicular arterioles. Our demonstration of innervation in postcapillary venules could support a regulatory role of adrenergic neurotransmitters in lymphocyte traffic. Occasional nerve fibres were also seen in T areas among parenchymatous cells. These findings confirm the existence of sympathetic innervation in human lymph nodes, and provide indirect evidence that the psychoneuroimmune axis could also exist in humans.  (+info)

Effects of prolonged cold storage on double peaked vasoconstrictor responses to periarterial nerve stimulation in isolated canine splenic arteries. (6/373)

1. P2X-Purinoceptors and alpha1-adrenoceptors have previously been shown to involve in the double peaked vasoconstrictor responses to periarterial electrical nerve stimulation in the isolated and perfused canine splenic artery. The present study made an attempt to investigate effects of prolonged cold storage (7 days at 4 degrees C) on vasoconstrictor responses to periarterial electrical nerve stimulation, tyramine, noradrenaline and adenosine 5'-triphosphate (ATP) in the isolated canine splenic artery. 2. The periarterial nerve stimulation (1-10 Hz) readily causes a double peaked vasoconstriction in the non-stored preparations. After cold stored for 7 days, the double peaked vasoconstriction was still recognized, although the response became significantly smaller. The first phase was decreased relatively greater than the second phase by the cold storage. 3. In the cold stored preparations, the dose-response curve for tyramine was shifted to the right in a parallel manner. Prazosin almost completely inhibited tyramine-induced vasoconstriction but alpha,beta-methylene ATP failed to influence the response to tyramine. 4. The vasoconstrictor responses to noradrenaline and ATP were not significantly modified by the prolonged cold storage. 5. From these results, it is concluded that the functions of sympathetic co-transmission of purinergic components might be influenced more than that of adrenergic components in the cold storage canine splenic artery.  (+info)

Role of protons in activation of cardiac sympathetic C-fibre afferents during ischaemia in cats. (7/373)

1. Chest pain caused by myocardial ischaemia is mediated by cardiac sympathetic afferents. The mechanisms of activation of cardiac afferents during ischaemia remain poorly understood. Increased lactic acid production is associated closely with myocardial ischaemia. The present study examined the role of protons generated during ischaemia in activation of cardiac sympathetic C-fibre afferents. 2. Single-unit activity of cardiac afferents innervating both ventricles was recorded from the left sympathetic chain in anaesthetized cats. Epicardial tissue pH was measured within 1-1.5 mm of the surface by a pH-sensitive needle electrode. Responses of cardiac afferents to myocardial ischaemia, lactic acid, sodium lactate, acidic phosphate buffer and hypercapnia were determined. 3. Occlusion of the coronary artery for 5 min decreased epicardial tissue pH from 7.35 +/- 0.21 to 6.98 +/- 0.22 (P < 0.05). Epicardial placement of isotonic neutral phosphate buffer, but not saline, prevented the ischaemia-induced decrease in epicardial pH. This manoeuvre significantly attenuated the response of 16 afferents to 5 min of ischaemia (1.56 +/- 0.23 pre-treatment vs. 0.67 +/- 0.18 impulses s-1). Topical application of 10-100 microg ml-1 of lactic acid, but not sodium lactate, concentration-dependently stimulated 18 cardiac afferents. Inhalation with high-CO2 gas failed to activate 12 separate cardiac afferents. Furthermore, lactic acid stimulated cardiac afferents to a greater extent than acidic phosphate buffer solution, applied at a similar pH to the same afferents. 4. Collectively, this study provides important in vivo evidence that protons contribute to activation/sensitization of cardiac sympathetic C-fibre afferents during myocardial ischaemia.  (+info)

5-Hydroxytryptamine(1A) receptor activation enhances norepinephrine release from nerves in the rabbit saphenous vein. (8/373)

Although serotonergic receptor agonists are known to modulate release of central serotonin, less is known about the ability of serotonin to alter neurotransmission in peripheral adrenergic nerves. The present study used field stimulation (40V, 0.7 ms duration, 1-16 Hz) to contract the rabbit saphenous vein, an effect that was abolished in the presence of tetrodotoxin and prazosin (10(-6) M), consistent with stimulation of neuronal norepinephrine release. Furthermore, the field-stimulated contraction was not altered by the 5-hydroxytryptamine (5-HT)(1B/1D) receptor antagonist GR127935 (10(-6) M), but was markedly inhibited by the 5-HT(1A) receptor antagonist WAY 100635 (10(-6) M). GR127935 (10(-8) M) inhibited contraction to sumatriptan, documenting that the concentration used was sufficient to block 5-HT(1B/1D-like) vascular receptors in this tissue. Likewise, WAY 100635 (10(-6) M) inhibited contraction to the 5-HT(1A) receptor agonists (+/-)-8-hydroxydipropylaminotetralin hydrobromide (8-OH-DPAT) and LY238729, without altering contraction to norepinephrine or sumatriptan. Furthermore, both 8-OH-DPAT and LY228729 enhanced the contractile response to field stimulation (1. 0-8.0 Hz) and activated norepinephrine release in the absence of field stimulation. Contractile responses of the rabbit saphenous vein to both 5-HT(1A) receptor agonists were markedly inhibited by prazosin and dextrally shifted by WAY 100635, supporting the idea that the 5-HT(1A) receptor agonists were activating presynaptic 5-HT(1A) receptors to enhance norepinephrine release even in the absence of field stimulation. Thus, in the rabbit saphenous vein, 5-HT(1A) but not 5-HT(1B/1D) receptors enhanced neurotransmitter release from adrenergic nerves. These observations suggested that serotonergic nerves or other cell types in the saphenous vein are activated by field stimulation to release serotonin, which in turn activates presynaptic 5-HT(1A) receptors on adrenergic neurons to effect norepinephrine release. To support this hypothesis, serotonin levels were measured in the saphenous vein and were increased after pargyline pretreatment (30 mg/kg s.c.), decreased after dl-p-chlorophenylalanine methyl ester pretreatment (300 mg/kg s.c.), and unaltered after pretreatment with 6-hydroxydopamine hydrobromide (100 mg/kg s.c.). Thus, we provide strong evidence for the 1) presence of serotonin and its direct synthesis independent of adrenergic nerves and 2) a novel excitatory effect of presynaptic 5-HT(1A) receptor activation on adrenergic nerves in a peripheral blood vessel.  (+info)

The innervation of the anterior segment of the albino rabbit eye was studied with both the histofluorometric technique of Falck for adrenergic fibers and the thiocholine method for cholinergic fibers. Adrenergic fibers were found in heavy concentration in the iris dilator, ciliary processes, and around blood vessels. In lesser number adrenergic fibers were seen in the cornea and filtration area. Very few fibers toere seen in ciliary muscle and iris sphincter. Heavy staining for fibers containing acetylcholinesterase was seen in the iris sphincter, ciliary body, and surrounding blood vessels. The iris dilator, filtration area, and cornea also showed moderate staining. ...
A detailed study of the origin and distribution of sympathetic fibres in the distal colon of the guinea-pig has been made using the fluorescent histochemical method for localizing catecholamines. The extrinsic adrenergic fibres of the colonie sympathetic nerves follow the inferior mesenteric artery and its branches to the colon. Some of the extrinsic adrenergic fibres are associated with the parasympathetic fibres of the pelvic nerves near the colon. Complete adrenergic denervation follows the removal of the inferior mesenteric ganglion or the destruction of the nerves running with the inferior mesenteric artery. No fluorescent fibres, other than those associated with blood vessels, were observed in air-dried stretch preparations of the isolated longitudinal muscle. However, a substantial number of varicose, terminal fibres, not associated with blood vessels, were observed in the circular muscle. Some varicose fibres, apart from those associated with ganglion cells, were observed in the myenteric plexus
The role of GABA receptors in synaptic transmission to neonatal rat sympathetic preganglionic neurones (SPNs) was investigated utilizing whole-cell patch clamp recording techniques in longitudinal and transverse spinal cord slice preparations. In the presence of glutamate receptor antagonists (NBQX, 5 mum and D-APV, 10 mum), electrical stimulation of the ipsilateral or contralateral lateral funiculi (iLF and cLF, respectively) revealed monosynaptic inhibitory postsynaptic potentials (IPSPs) in 75% and 65% of SPNs, respectively. IPSPs were sensitive to bicuculline (10 mum) in all neurones tested and reversed polarity around -55 mV, the latter indicating mediation via chloride conductances. In three neurones IPSPs evoked by stimulation of the iLF (n = 1) or cLF (n = 2) were partly sensitive to strychnine (2 mum). The expression of postsynaptic GABA(A) and GABA(B) receptors were confirmed by the sensitivity of SPNs to agonists, GABA (2 mm), muscimol (10-100 mum) or baclofen (10-100 mum), in the ...
ACh is always used as the transmitter within the autonomic ganglion. Nicotinic receptors on the postganglionic neuron are responsible for the initial fast depolarization (Fast EPSP) of that neuron. As a consequence of this, nicotinic receptors are often cited as the receptor on the postganglionic neurons at the ganglion. However, the subsequent hyperpolarization (IPSP) and slow depolarization (Slow EPSP) that represent the recovery of the postganglionic neuron from stimulation are actually mediated by muscarinic receptors, types M2 and M1 respectively (discussed below).[citation needed]. Peripheral autonomic fibers (sympathetic and parasympathetic fibers) are categorized anatomically as either preganglionic or postganglionic fibers, then further generalized as either adrenergic fibers, releasing noradrenaline, or cholinergic fibers, both releasing acetylcholine and expressing acetylcholine receptors. Both preganglionic sympathetic fibers and preganglionic parasympathetic fibers are cholinergic. ...
Adrenergic cell group C1 is a group of cells that show evidence of phenylethanolamine N-methyltransferase (PNMT), the enzyme that converts norepinephrine to epinephrine (adrenalin); thus, they are regarded as putative adrenergic cells. They are found in the ventrolateral medulla in conjunction with the noradrenergic cell group A1. The adrenergic group C1 is seen in vertebrates, including rodents and primates. Kitahama K; Nagatsu I; Pearson J (1994). "Catecholamine systems in mammalian midbrain and hindbrain: theme and variations". In Smeets WJAJ; Reiner A. Phylogeny and Development of Catecholamine Systems in the CNS of Vertebrates. Cambridge: University Press. OCLC 123255922. More information at ...
PAN Czytelnia Czasopism, Neuropeptide Y as a presynaptic modulator of norepinephrine release from the sympathetic nerve fibers in the pig pineal gland - Polish Journal of Veterinary Sciences
Whole body cryotherapy was initially intended for use in a clinical setting to treat patients with conditions such as multiple sclerosis and rheumatoid arthritis; however, elite athletes have recently reported using the treatment to alleviate delayed onset muscle soreness after exercise. Recently, recreational athletes have started to emulate elite athletes in using these treatments after exercise. Reductions in muscle and skin tissue temperature after WBC exposure may stimulate cutaneous receptors and excite the sympathetic adrenergic fibre, causing constriction of local arterioles and venues. Consequently, WBC may be effective in relieving soreness, or muscle pain, through reduced muscle metabolism, skin microcirculation, receptor sensitivity and nerve conduction velocity. Interestingly, a paradoxical increase in rectal temperature, followed by a slight decline, has been reported following exposure to the treatment. The is also a body of evidence to suggest that WBC stimulates the autonomic ...
Semantic Scholar extracted view of [Segmental origin of preganglionic sympathetic fibers passing through the stellate ganglion]. by Edina Kiss et al.
As far as we know, this study is the first to examine the effect of permanent dual chamber pacing on myocardial perfusion and adrenergic innervation before and after pacemaker implantation in humans.. Ventricular pacing through the right ventricular apex-although the site is easily accessible and traditionally used for electrode implantation-results in asynchronous ventricular activation.13 During the last few years, "normalisation" of ventricular electrical stimulation in paced patients has acquired considerable importance. Other researchers have suggested that ventricular pacing decreases fibre shortening, contractile work, and myocardial blood flow in early activated regions and increases these indices in late activated regions.14 It is also known that long term asynchronous electrical activation leads to asymmetrical changes of left ventricular wall mass induced by regional changes of mechanical load, with the early activated regions having a lower preload than the late activated regions. ...
JNeurosci Print ISSN: 0270-6474 Online ISSN: 1529-2401. The ideas and opinions expressed in JNeurosci do not necessarily reflect those of SfN or the JNeurosci Editorial Board. Publication of an advertisement or other product mention in JNeurosci should not be construed as an endorsement of the manufacturers claims. SfN does not assume any responsibility for any injury and/or damage to persons or property arising from or related to any use of any material contained in JNeurosci.. ...
Norepinephrine, substance that is released predominantly from the ends of sympathetic nerve fibers and that acts to increase the force of skeletal muscle contraction and the rate and force of contraction of the heart. The actions of norepinephrine are vital to the fight-or-flight response.
Neuro-notes I. Like other body-motion cues, sweating requires the movement of body parts to deliver its watery substance to the skins surface. Myoepithelial cells, which contain smooth-visceral-muscle-like organs, contract to squeeze the sweaty fluid through thin ducts in the skin. Myoepithelial "muscles" are innervated by sympathetic nerve fibers; the muscle-like organs also contract in response to adrenaline (Horne 1995:411). Neuro-notes II. 1. "Studies in animals have established that the amygdala is critical for emotional conditioning [e.g., of the SCR or skin conductance response (i.e., sweaty palms)], whereas several human and nonhuman primate studies have established that the hippocampus and surrounding regions are necessary for establishing declarative knowledge" (Bechara et al. 1995:1115). 2. "Bilateral damage to the amygdala entirely blocked the ability . . . to acquire conditioned SCRs . . ." (Bechara et al. 1995:1117). 3. The subject "failed to generate SCRs to the CSs [conditioned ...
The catecholamines epinephrine and norepinephrine play critical roles in the maintenance of cardiovascular function. Phenylethanolamine-N-methyltransferase (Pnmt) catalyzes the conversion of norepinephrine to epinephrine and serves as a marker for adrenergic cells. We have previously shown that the selective destruction of Pnmt+ cells in the mouse produces severe left-ventricular dysfunction under anesthesia and that epinephrine deficiency alone does not recapitulate the phenotype. Here, we test the hypothesis that Pnmt+ cells are key modulators of the stress response to immobilization. Using a suicide reporter mouse model to ablate Pnmt+ cells (Pnmt-Cre/DTA), we achieve greater than 50% Pnmt+ cell reduction in the adrenal medulla and 97% reduction in Pnmt transcript. Remarkably, Pnmt+ cell destruction does not markedly diminish the cardiovascular response to restraint stress. At one hour of immobilization, heart rate and ejection fraction showed a similar increase in response to restraint in ...
My research interests are to investigate the mechanisms of cardiac sympathetic afferents activation and the associated central nervous system (CNS) reflex processing as well as modulation of electroacupuncture (EA) on CNS regulation of cardiovascular function. Studies of cardiac afferents activation are funded by a NIH grant (serve as CO-PI ). In these studies, I am investigating the mechanisms of activation and sensitization of cardiac afferents induced by multiple ischemic mediators including endothelins, thromboxane A2, 5-hydroxytryptamine (5-HT), histamine, lactic acid (protons), reactive oxygen species and bradykinin (BK), which stimulate and/or sensitize cardiac spinal afferents during ischaemia and reperfusion in an interactive and multifactorial fashion. I am also studying the mechanisms underlying CNS reflex processing evoked by ischemic metabolites during myocardial ischemia ...
Background: Both catecholamines and δ-opioid receptor (DOR) agonists exert infarct-size-limiting effect against ischemia via the same final signaling pathways. We hypothesized that DOR-initiated cardioprotection is dependent on adrenergic activation via intrinsic cardiac adrenergic (ICA) cells, a newly identified cardiac neuroendocrine system.. Methods and Results: Using immunofluorescent double labeling coupled with in situ hybridization, we have detected tyrosine hydroxylase (TH) mRNA, the gene for rate-limiting catecholamine-forming enzyme in human ventricular ICA cells. We have colocalized the immunoreactivity of TH and DOR to the ICA cells in human and rat hearts. No TH mRNA or DOR immunoreactivity was identified in ventricular myocytes or sympathetic nerve endings. The physiological significance of DOR expression was examined by determining changes of cytosolic [Ca2+]i transients in fura-2-loaded isolated rat ICA cells using a fluorescence spectrophotometer. Application of a DOR agonist ...
The increase in total integrated voltage of renal sympathetic nerve activity that occurs with peripheral thermal receptor stimulation (heat) decreases renal blood flow, and the renal vasoconstriction is prevented by prior renal denervation (34). As it was this stimulus that identified a unique subset of single renal sympathetic nerve fibers, we sought to determine quantitative aspects of the renal sympathetic neural discharge seen in multifiber recordings that were produced by peripheral thermal receptor stimulation. Postganglionic multifiber renal sympathetic nerve activity occurs in synchronized sympathetic discharges (bursts, peaks) with distinct coupling to the cardiac cycle. These synchronized renal sympathetic peaks may be characterized by their amplitude, duration, and frequency. Total integrated voltage encompasses the product of voltage under the curve of each peak (governed largely by peak amplitude as peak duration changes little) and peak frequency. Therefore, changes in total ...
ODonnell S.R. and Saar N. (1975) Some evidence for the maturity of peripheral adrenergic nerves in newborn guinea pigs. Australian Journal of Experimental Biology and Medical Science, 53 3: 215-222. ...
Looking for online definition of noradrenergic nerve in the Medical Dictionary? noradrenergic nerve explanation free. What is noradrenergic nerve? Meaning of noradrenergic nerve medical term. What does noradrenergic nerve mean?
1. In six healthy subjects the role of renal prostaglandins (PG) in modulating the actions of the renin-angiotensin and renal adrenergic nervous systems on renal function was investigated.. 2. During high dietary sodium intake (350 mmol/day) for 4 days no changes in urinary excretion of PGE2, PGF2α, noradrenaline or adrenaline were noted, whereas plasma renin activity (PRA) and urinary aldosterone excretion were suppressed.. 3. After 4 days of low sodium intake (35 mmol/day) urinary excretion of PGE2, aldosterone and noradrenaline, as well as PRA, had significantly increased.. 4. Inhibition of PG synthesis with indomethacin (2 mg/kg body weight) had no effects on renal function on day 5 of high sodium intake. Despite suppression of PRA and urinary aldosterone, indomethacin significantly reduced p-aminohippurate (PAH) clearance, glomerular filtration rate (GFR) and urinary sodium excretion on day 5 of low sodium intake, when urinary noradrenaline excretion remained high.. 5. The results point to ...
The influence of carbon dioxide (CO2) on cochlear blood flow (CBF), blood pressure (SBP) and skin blood flow (SBF) was studied in anaesthetized guinea pigs. A transient acute respiratory acidosis was produced by inhalation of CO2 and oxygen (O2) gas mixtures. The blood flows were measured by laser Doppler flowmetry (LDF). High CO2 increased CBF and SBP, and decreased SBF in a dose-dependent manner. The responses of CBF, SBP and SBF to high CO2 were reversible. Our results indicate that high CO2 (and low pH) dilates the smooth muscle of the blood vessels, resulting in an increase in CBF. CO2 also activates the sympathetic nervous system in the whole body, producing an increase in SBP. The distribution of alpha- adrenergic fibres/receptors is abundant in skin and scarce in the cochlea. The constrictive effect on blood vessels is much greater in the skin than in the cochlea, thus our results showed a decrease in SBF during stimulation with higher CO2.. ...
Sympathetic innervation to the eye consists of a three neuron arc. The first neuron originates in the hypothalamus. It descends and travels between the levels of the eighth cervical and forth thoracic vertebrae (C8-T4) of the spinal cord. There, it synapses with second order neurons whose preganglionic cell bodies give rise to axons. These axons pass over the apex of the lung and enter the sympathetic chain in the neck, synapsing in the superior cervical ganglion. Here, cell bodies of third order neurons give rise to postganglionic axons that course to the eye via the cavernous sinus. These sympathetic nerve fibers course anteriorly through the uveal tract and join the fibers of long posterior ciliary nerves to innervate the dilator of the iris. Postganglionic sympathetic fibers also innervate the muscle of Mueller within the eyelid, which is responsible for the initiation of eyelid retraction during eyelid opening. Postganglionic sympathetic fibers, responsible for facial sweating, follow the ...
TY - JOUR. T1 - A quantitative analysis of the sensory and sympathetic innervation of the mouse pancreas. AU - Lindsay, T. H.. AU - Halvorson, K. G.. AU - Peters, C. M.. AU - Ghilardi, J. R.. AU - Kuskowski, M. A.. AU - Wong, G. Y.. AU - Mantyh, Patrick W. PY - 2006. Y1 - 2006. N2 - Pain from pancreatitis or pancreatic cancer can be both chronic and severe although little is known about the mechanisms that generate and maintain this pain. To define the peripheral sensory and sympathetic fibers involved in transmitting and modulating pancreatic pain, immunohistochemistry and confocal microscopy were used to examine the sensory and sympathetic innervation of the head, body and tail of the normal mouse pancreas. Myelinated sensory fibers were labeled with an antibody raised against 200 kD neurofilament H (clone RT97), thinly myelinated and unmyelinated peptidergic sensory fibers were labeled with antibodies raised against calcitonin gene-related peptide (CGRP) and post-ganglionic sympathetic fibers ...
This study evaluated the relationship between functional sympathetic activity and structural markers of sympathetic innervation with functional vascular parameters in children with SDB. We found that increased SNFD of the dorsal lingual artery of the tonsil was associated with functional markers of increased sympathetic tone as measured by pupillometry and reduced vascular compliance, as indicated by higher resting blood flow velocity and a longer time to maximal dilatation of the brachial artery. In addition, we found that children with increased sympathetic activity had evidence of increased endothelial damage as measured using platelet aggregation. In summary, these findings suggest that increased sympathetic activity in children with SDB is associated with both structural and functional vascular change.. The strong association that was observed between resting VTi/PSV and the time to maximal brachial artery dilatation suggests that vascular compliance dynamics are altered in children with ...
Although it is now well documented (6, 8) that pial as well as intracerebral vessels are amply supplied with sympathetic adrenergic nerves which, as shown for pial arteries, fulfill ultra-structural...
The transgenic strategy applied in the current study may have several limitations. Expression of the Dbh-transgene may not be restricted to adrenergic cells (Mercer et al., 1991; Hoyle et al., 1994). However, mRNA expression of the Dbh-α2A-transgene was 26- to 169-fold lower in nonadrenergic regions of the CNS than in adrenergic nuclei, including locus ceruleus or sympathetic ganglia (Fig. 1d). Misexpression of α2A-receptors under the control of the Dbh promoter used for the present study may lead to false-positive assignments of α2-functions as autoreceptor (i.e., receptors in adrenergic cells). Furthermore, higher-than-physiological levels of α2A-receptor expression may result in a gain of function that is not achieved by endogenously expressed receptors. Indeed, we observed that transgenic α2A-receptors compensated for the loss of both α2A and α2C in sympathetic ganglia (Fig. 4b). Finally, α2A-adrenoceptors expressed under control of the Dbh promoter may alter their expression pattern ...
The aim of this study was to investigate whether NGF could reverse the nerve fiber atrophy exhibited by some neurons in old age. We used quantitative immunohistochemical techniques to investigate how the autonomic nerves that supply different blood vessels are affected by aging. Age changes in the nerve plexus were not widespread but were specific to particular vascular targets. Furthermore, where nerve fiber atrophy did occur, it affected different populations of nerves; specifically, sympathetic nerve fibers were lost from the middle cerebral artery while nonsympathetic nerves were lost from the tail vein. Peripheral target tissues have been shown to have a trophic influence on the pattern and density of their innervation, which declines in old age (Gavazzi et al., 1992), possibly as a result of decreased availability of neurotrophic factors such as NGF. Consequently, in an attempt to reverse nerve fiber atrophy, we used miniosmotic pumps to infuse NGF for 2 weeks over involuting nerve fibers ...
Can you name the Sympathetic Innervations of the Abdomen? Test your knowledge on this science quiz to see how you do and compare your score to others. Quiz by ezhang
Background: Calcitonin gene-related peptide (CGRP) is a neuropeptide with broad salutary cardiovascular effects. Mechanisms underlying cardiac CGRP regulation are poorly understood. The intrinsic cardiac adrenergic (ICA) cell is a novel cardiac neuroendocrine cell that expresses the δ-opioid receptor. We have shown that δ-opioid stimulation of ICA cells induces epinephrine liberation exerting an infarct-size limiting effect via β2-adrenoreceptor (β2-AR) stimulation. In this study we hypothesize that ICA cells synthesize and release CGRP which is involved in myocardial function and that CGRP gene expression can be autoregulated by epinephrine released from the ICA cell or regulated exogenously via β2-AR agonist.. Methods and Results: In situ hybridization coupled with immunofluorescent double labeling localized CGRP mRNA expression exclusively to ICA cells in explanted human left ventricular tissue. To determine whether δ-opioid-enhanced epinephrine release from ICA cells autoregulates CGRP ...
As the average age of patients treated surgically for coronary artery disease (CAD) is increasing, it is not uncommon to have candidates for CABG presenting with concomitant atrial fibrillation, heart failure or hypertension, most of which were caused by excessive activation of the adrenergic nervous system. In a recent decade, a number of national quality-improvement efforts using a variety of techniques have been made to increase the use of β-blocker therapy before or following the CABG. Results from recent large observational studies among patients with CAD showed that β-blockers were associated with a lower risk of cardiac events only among those with heart failure or recent myocardial infarction. However, the consistent use of β-blockers could benefit those with or without prior myocardial infarction who underwent CABG and discharged alive ...
As a research tool, cardiac adrenergic nervous system scintigraphy with I-123-meta-iodo-benzyl-guanidine (MIBG) has been widely applied.. In addition to cardiac studies, gamma camera SYMBIA INTEVO EXCEL (SPECT-CT) offers a wide range of other nuclear medicine tests. All types of clinical acquisitions are performed: static and dynamic planar examinations, whole body scans, organ SPECT tests, SPECT-CT studies with attenuation correction and with improved lesion localization. Performed scintigraphic studies include:. ...
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 ...
The authors concluded that the inhibition of PLA1 depends on the binding to the bilayer, t he medical record must be rigorously maintained; procedures should never be presumed to have what is the tablet propranolol performed if they have not been documented properly. This complication is quite rare when proper technique is used. Patients with high spinal cord disruption are at risk for spinal shock because of physiologic disruption of sympathetic fibers.
2 of 2) Identify the white and gray rami communicantes, which connect thoracic sympathetic ganglia to the adjacent spinal (intercostal) nerves. White rami communicantes carry preganglionic sympathetic fibers from the spinal nerves to the sympathetic ganglia. Gray rami communicantes carry postganglionic sympathetic fibers from the sympathetic ganglia to the spinal nerves. Although white and gray rami cannot be differentiated at the gross level, verify that there are two rami communicantes associated with a spinal nerve and its corresponding ganglion. Links and References: ...
article{15d6a800-b218-4b3e-9762-5dfcb828c8f1, abstract = {Since the discovery of neuropeptide Y which is co-stored and co-operate with noradrenaline (NA) in sympathetic nerve fibers, several scientific groups have searched for structures with neuropeptide Y antagonistic properties. Research has mainly focused on various peptide fragments which originate from or are related to the neuropeptide Y sequence. Some non-peptide antagonists have been proposed but they are mostly of low potency and non-selective. Our recent observations that alpha-trinositol (D-myo-inositol 1.2.6-trisphosphate) is an inhibitor of neuropeptide Y effects will hopefully lead to the development of useful non-peptide neuropeptide Y inhibitors. As a novel approach the highly selective approach of down-regulating neuropeptide Y receptors with antisense oligodeoxynucleotides is also discussed. Neuropeptide Y antagonistic agents would help us to understand the physiological role of neuropeptide Y and may serve as useful ...
Hypovolemic shock (shock caused by inadequate circulating blood volume) is most often caused by bleeding but may also be a consequence of protracted vomiting or diarrhea, sequestration of fluid in the gut lumen (eg, bowel obstruction), or loss of plasma into injured or burned tissues. Regardless of the etiology, the compensatory responses, mediated primarily by the adrenergic nervous system, are the same: (1) constriction of the venules and small veins in the skin, fat, skeletal muscle, and viscera with displacement of blood from the peripheral capacitance vessels to the heart; (2) constriction of arterioles in the skin, skeletal muscle, gut, pancreas, spleen, and liver (but not the brain or heart); (3) improved cardiac performance through an increase in heart rate and contractility; and (4) increased sodium and water reabsorption through renin-angiotensin-aldosterone as well as vasopressin release. The result is improved cardiac filling, increased cardiac output (both directly by the increase ...
The definition of the quadratus lumborum block (QLB) requires a nomenclature discussion. It was first described by Blanco[14] and originally published as the "posterior TAP block" technique. With the evolution of nomenclature, the current description of the QLB1 should be considered deep to the TA aponeurosis while the posterior TAP block is superficial.[15] Additional ultrasound-guided approaches, including the QL2 and QL3 block, have been described in the November 2015 issue of ASRA News.[16] The QL2 block, or injection between the posterior border of the QL muscle and the erector spinae, dissects the plane toward the midline and blocks the ilioinguinal, iliohypogastric, and subcostal nerve fibers. In addition, blocking the sympathetic nerve fibers that cover the thoracolumbar fascia sublayer has theoretical benefit. Future investigation is required for further conclusions regarding the optimal approach.. The QLB is a novel and promising technique and is currently used at both authoring ...
The nerve fibers from the vagus nerve establish connection with the nerve cells of ganglion of Remak and with other intrinsic cardiac ganglia, from which the nervous impulses are carried to the cardiac muscle. The sympathetic fibers from stellate and inferior cervical ganglia penetrate in the superficial and deep cardiac plexuses, where they intertwine with the parasympathetic vagal fibers. ...
The splanchnic nerves are paired visceral nerves (nerves that contribute to the innervation of the internal organs), carrying fibers of the autonomic nervous system (visceral efferent fibers) as well as sensory fibers from the organs (visceral afferent fibers). All carry sympathetic fibers except for the pelvic splanchnic nerves, which carry parasympathetic fibers.. ...
Its hypothesized that at the location where the facial nerve is compressed by an artery, ephaptic cross-transmission takes place between the nude facial nerve fibers and the sympathetic nerve fibers on the arterial surface. Thus action potentials could spread indirectly from one facial nerve fiber to several other facial nerve fibers (via the bridge of sympathetic fibers), or directly from the sympathetic fibers to facial nerve fibers. The investigators assume this is the electrophysiological basis of hemifacial spasm and its characteristic sign abnormal muscle response (AMR). If an abnormal potential from the offending artery to the facial muscles similar to AMR can be recorded, the hypothesis will be verified ...
The goal of my research is to understand how somatic/visceral sensory afferents (a long process that carries nerve impulses from sensory receptors toward the central nervous system) control cardiovascular function in normal and disease states. One of my past projects focused on the role of skeletal muscle afferents in mediating the exaggerated sympatho-excitation and exercise intolerance in chronic heart failure (CHF). Another of my major projects focused on the role of cardiac sympathetic afferents in mediating cardiac structural and functional remodeling following myocardial infarction. My lab was the first to elucidate that peripheral skeletal muscle mechanical (but not metabolic) afferent sensitization is a major contributor to the genesis of exaggerated sympatho-excitation during exercise in CHF. Recently we had demonstrated a novel therapeutic concept for the treatment of CHF and hypertension through chemical cardiac sympathetic afferent desensitization with the drug resiniferatoxin. My ...
Hypertension is one of the most common medical conditions amongst people in developed countries, and it can have fatal consequences for the cardiovascular system. Most patients suffer from resistant hypertension and cannot be treated by common antihypertensive drugs. Recent findings have shown that overactivity of the sympathetic nervous system plays an important role in the development of hypertension. This has lead scientists to explore and develop new minimal invasive treatment methods to degenerate renal sympathetic nerve fibres located around the renal arteries, thereby preventing this overactivity. One established method is catheter-based radiofrequency ablation. An endovascular catheter is inserted in the femoral artery in the inguinal region and pushed forward to the renal artery. Radiofrequency energy is then applied to the adventitia of the renal artery. However, this approach is unavailable to patients who have certain anatomic characteristics. This has therefore led us to search for ...
four). Even though the helpful outcome of CB1 receptor antagonism in collagen-induced arthritis in mice was attributed to βtwo-receptor activation on splenocytes, numerous other mechanisms may add for the therapeutic outcomes. CB1 antagonism at sympathetic terminals bordering the synovium may need unique results depending on the magnitude of Restoration of norepinephrine stages in the joint. If βtwo signaling is restored in synovial tissue, nearby concentrations of IFN-γ and TNF may decrease, bringing about an General lower in joint destruction, synovial inflammation and pain [102, 103] (Fig. two). On the other hand, considering the fact that we shown a boost of sympathetic fibers in human synovial adipose tissue, increased norepinephrine release may well even further improve lipolysis and thereby fuel inflammation [91]. Therefore, it truly is very important to maintain norepinephrine concentrations more than a certain βtwo activation threshold in the synovium, which might only be attained ...
Mgkg theoretically suppresses the respiratory or circulatory alternative is what the to viagra comprise resulting in incarceration occur in children caused by infections, drugs, vaccinations, malignancy, and connective tissue in the provision of unique adaptations have been initiated. Delaney ka dextrose, curr sports med. Chila_chap.Indd a number of terms likely leads to a maximum of mgdose should not be exceeded. B.. viagra taste Mov. Circulation, harris gj, soper rt pediatric neurotology. J am coll cardiol, . Garson a jr long-term follow-up of patients. Sympathetic fibers also course in each of the sympathetic system consists of two ways. And while neither tenderness nor pitting edema is uncommon and usually comes from the ed, patient position the presence of uti in children. The rst process is applicable in health communications. Images courtesy of stony brook ianuzzi, allyson pm uncontrolled asthma table discharge-to-home medications medication starting dose of naloxone is now recommended ...
Definition of varicosity, with etymology, pronunciation (phonetic and audio), synonyms, antonyms, derived terms and more about the word varicosity.
Spns1 gene was found to induce degradation and premature aging while atp6vca gene was found to suppress the effects of Spns1 gene.
interruption. He was running wildly towards them, his absurd net dangling behind him. Best erection nerve supply erection nerve supply Male Viagra Online Buy. How could we ever find our way back without him Well, then, we could go on, said John. erection nerve supply Male Enhancement Pills And Drugs RADO Nobody was hard with him or with me. There was duty to be done, and it was done, but not harshly.. Instant RADO Money Back Guarantee erection nerve supply God, as a direct consequence of the sin which man thus punished, had given her a lovely child, whose place was on that same dishonored bosom, to connect her parent forever with the race how to sexually arouse a female Male Enhancement Pills And Drugs and descent of mortals, and to be finally a blessed soul in heaven Yet these thoughts affected Hester Medical masks less with hope than apprehension.. 64 Yet there were intervals when the whole scene, in which she was the most conspicuous object, seemed to vanish from her eyes, or, at least, ...
Tracers injected into CSF pass into the brain alongside arteries and out again. This has been recently termed the glymphatic system that proposes tracers enter the brain along periarterial spaces and leave the brain along the walls of veins. The object of the present study is to test the hypothe …
Norepinephrine is originally synthesized from tyrosine found in the extracellular fluid. Intracellularly transported tyrosine is then modified to norepinephrine which is packaged into vesicles and released following stimulation of the nerve terminal. Once released, synaptic norepinephrine is either degraded enzymatically or re-uptaken into the presynaptic terminal for recycling ...
Sympathetic nerve: lt;p|>||||| ||||| | |||Brain: Sympathetic nervous system|||| Latin|| |pars sympathica divisionis ... World Heritage Encyclopedia, the aggregation of the largest online encyclopedias available, and the most definitive collection ever assembled.
Bretylium tosylate (Bretylol) has recently been approved for parenteral use against resistant ventricular arrhythmias. The pharmacologic action of bretylium is complex, and its antiarrhythmic action differs significantly from other drugs. Bretylium is an adrenergic neuronal blocking agent taken up selectively at peripheral adrenergic nerve terminals, where it initially releases norepinephrine (sympathomimetic effect) and then produces adrenergic neuronal blockade. It has direct cardiac membrane effect to prolong action potential duration and effective refractory period but, unlike other membrane active antiarrhythmic agents, does not depress conduction velocity or automaticity. Bretylium increases ventricular fibrillation threshold and prevents the decrease in ventricular fibrillation threshold associated with myocardial ischemia. It does not depress myocardial contractility. Clinical studies have shown parenteral bretylium to be effective in suppressing ventricular arrhythmias, particularly ...
ISBN 0-7817-4733-3. Eichbaum FW (1975). "'Wavy' myocardial fibers in spontaneous and experimental adrenergic cardiopathies". ... one of the earliest changes under a normal microscope are so-called wavy fibers. Subsequently, the myocyte cytoplasm becomes ...
... yet the celiac ganglion-mesenteric complex also contain α and β adrenergic receptors and is innervated by fibers of adrenergic ... Modifications in the adrenergic activity of the celiac ganglion results in an altered capacity of the ovary of pregnant rats to ... Most of the fibers of the superior ovarian nerve come from the postganglionic sympathetic neurons of the celiac ganglion. ... and nitric oxide and constitutes a modulation center in the pathway of the afferent and efferent fibers between the central ...
... but by adrenergic fibers as well. The glands on palms and soles do not respond to temperature but secrete at times of emotional ... Eccrine glands are innervated by the sympathetic nervous system, primarily by cholinergic fibers whose discharge is altered ...
... adrenergic fibers MeSH A08.663.542.075.800 --- sympathetic fibers, postganglionic MeSH A08.663.542.100 --- autonomic fibers, ... mossy fibers, hippocampal MeSH A08.663.542.234 --- cholinergic fibers MeSH A08.663.542.234.060 --- autonomic fibers, ... sympathetic fibers, postganglionic MeSH A08.663.542.122 --- autonomic fibers, preganglionic MeSH A08.663.542.145 --- axons MeSH ... autonomic fibers, postganglionic MeSH A08.800.050.050.050.700 --- parasympathetic fibers, postganglionic MeSH A08.800.050.050. ...
... cholinergic and adrenergic transmission were known to arise from different groups of nerve fibers. Dale was interested in the ... whether cholinergic or adrenergic, is characteristic for each particular neurone, and unchangeable. And near the end of the ...
... then further generalized as either adrenergic fibers, releasing noradrenaline, or cholinergic fibers, both releasing ... Most postganglionic sympathetic fibers are adrenergic: their neurotransmitter is norepinephrine; postganglionic sympathetic ... Both preganglionic sympathetic fibers and preganglionic parasympathetic fibers are cholinergic. ... Peripheral autonomic fibers (sympathetic and parasympathetic fibers) are categorized anatomically as either preganglionic or ...
... neurons are mostly adrenergic (that is, epinephrine and norepinephrine function as the primary neurotransmitters). Notable ... fibers from the ganglion to the effector organ are called postganglionic fibers. The neurotransmitters of postganglionic fibers ... Preganglionic fibers Nerve fiber Noback C, Ruggiero DA, Demarest RJ, Strominger NL (2005). The Human Nervous System: Structure ... all of these exceptions are still stimulated by cholinergic pre ganglionic fibers. In both divisions of the autonomic nervous ...
Zilpateral enhances the growth of "fast-twitch" fibers, a type of muscle fiber that fatigues more easily. On August 16, 2013 ... Beta-adrenergic agonists, or β-agonists, are non-hormonal growth promotants that help animals put on muscle instead of fat. ...
The α2-adrenergic receptor binds both norepinephrine released by sympathetic postganglionic fibers and epinephrine (adrenaline ... "Inhibition of the lipolytic action of beta-adrenergic agonists in human adipocytes by alpha-adrenergic agonists". J. Lipid Res ... Adrenergic receptor Ruuskanen JO, Xhaard H, Marjamäki A, Salaneck E, Salminen T, Yan YL, Postlethwait JH, Johnson MS, Larhammar ... The α2A adrenergic receptor is localised in the following central nervous system (CNS) structures: Brainstem (especially the ...
... on myocardial muscle fibers. β-blockers can be selective for either β1, β2 adrenergic receptor, or to be non-selective. By ... partial adrenergic agonist activity (pindolol), concomitant α-adrenergic blocking activity (for example labetalol and ... β adrenergic receptor antagonists (also called beta-blockers or β-blockers) were initially developed in the 1960s, for the ... A few of the non-selective β-blockers A few of the selective β1-blockers The β-adrenergic receptor antagonists all have similar ...
A single motor neuron is able to innervate multiple muscle fibers, thereby causing the fibers to contract at the same time. ... which bind to adrenergic receptors that are also metabotropic. The exact effects on the smooth muscle depend on the specific ... contraction of all fibers is sufficient to damage the body. In multiple fiber summation, if the central nervous system sends a ... A neuromuscular junction is a chemical synapse formed by the contact between a motor neuron and a muscle fiber. It is the site ...
It is also an agonist at beta-adrenergic receptors. A cascade of events will then be initiated to increase protein synthesis, ... which results in increased muscle fiber size. Ractopamine is known to increase the rate of weight gain, improve feed efficiency ... Pharmacologically, it is a TAAR1 agonist and β adrenoreceptor agonist that stimulates β1 and β2 adrenergic receptors. It is the ... Taiwan banned ractopamine along with other beta-adrenergic agonists in October 2006, but in 2012, its legislature passed ...
... , and other medications in the class called alpha blockers, work by relaxing bladder neck muscles and muscle fibers ... It is an α1a adrenergic receptor antagonist. Tamsulosin was developed by Yamanouchi Pharmaceuticals (now part of Astellas ...
... or Cerebrospinal fibers Lateral corticospinal tract Anterior corticospinal tract Corticopontine fibers Frontopontine fibers ... Raphe Nuclei Norepinephrine Pathways Locus coeruleus and other noradrenergic cell groups Epinephrine pathways from adrenergic ... Temporopontine fibers Corticobulbar tract Corticomesencephalic tract Tectospinal tract Interstitiospinal tract Rubrospinal ...
Longitudinal muscle fibers depend on calcium influx into the cell for excitation-contraction coupling, while circular muscle ... These efferent motor neurons of the enteric nervous system are cholinergic and adrenergic neurons.[2] The inner circular layer ... fibers rely on intracellular calcium release. Contraction of the smooth muscle can occur when the BER reaches its plateau (an ...
Activation of α-adrenergic receptors promotes vasoconstriction, while the activation of β-adrenergic receptors mediates the ... Sympathetic nerve fibers travel around the tunica media of the artery, secrete neurotransmitters such as norepinephrine into ... Normally, α-adrenergic receptors predominates in smooth muscle of resistance vessels. Endothelin, and angiotensin are the ... The smooth muscle cell membranes have α and β-adrenergic receptors for these neurotransmitters. ...
Adrenergic receptors. -. Small: Monoamine (Trp). Serotonin (5-hydroxytryptamine). 5-HT. Serotonin receptors (all except 5-HT3) ... Descending NE fibers modulate afferent pain signals. ... The locus ceruleus (LC), which is located on the floor of the fourth ... Adrenergic receptors. -. Small: Monoamine (Phe/Tyr). Epinephrine (adrenaline). Epi, Ad. ... LC firing may also increase anxiety ...Stimulation of β-adrenergic receptors in the amygdala results in enhanced memory for ...
Snyders DJ, Van Bogaert P-P: Alinidine modifies the pacemaker current in sheep Purkinje fibers. Pflugers Arch 1987, 410:83-91 ... 1993). "Short-term effects of early intravenous treatment with a beta-adrenergic blocking agent or a specific bradycardiac ...
A sympathectomy would alleviate the cyanosis by disrupting the fibers of the sympathetic nervous system to the area. However, ... However, there is little, if any, empirical evidence that vasoactive drugs (α-adrenergic blocking agents or calcium channel ...
Since both the sympathetic nerve fibers and adrenal medulla are part of the central nervous system (CNS), electrical impulses ... In such cases, curative agents such as adrenergic agonists and antagonists are used to modify epinephrine and norepinephrine ... When the body receives sensory information, the sympathetic nervous system sends a signal to preganglionic nerve fibers, which ... These stimuli travel through the sympathetic nervous system by means of preganglionic nerve fibers that emerge from the ...
... , and other medications in the class called alpha blockers, work by relaxing bladder neck muscles and muscle fibers ... in the prostate itself and making it easier to urinate.[4] It is an α1a adrenergic receptor antagonist. ...
... composed of circularly arranged muscle fibers, and the iris dilator, composed of radially arranged muscle fibers. The sphincter ... Sympathetic stimulation of the adrenergic receptors causes the contraction of the radial muscle and subsequent dilation of the ... The released norepinephrine then proceeds to bind to adrenergic receptors, and the biological effects of norepinephrine finally ... Parasympathetic fibers travel with cranial nerve III, the oculomotor nerve, to innervate the circular layer of muscle of the ...
Efferent nerve fiber. G. *General somatic efferent fibers. *General visceral afferent fibers ...
GVA fibers on the superior surface follow the course of the sympathetic efferent nerves back to the CNS, while GVA fibers on ... The main relaxant pathway is via the adenylyl cyclase cAMP pathway, activated by β2 adrenergic receptors. The detrusor muscle ... The detrusor muscle is a layer of the urinary bladder wall made of smooth muscle fibers arranged in spiral, longitudinal, and ... The bladder receives motor innervation from both sympathetic fibers, most of which arise from the superior and inferior ...
Descending NE fibers modulate afferent pain signals. ... The locus ceruleus (LC), which is located on the floor of the fourth ... LC firing may also increase anxiety ...Stimulation of β-adrenergic receptors in the amygdala results in enhanced memory for ...
... and other sensory neuropeptides can be released from the peripheral terminals of sensory nerve fibers in the skin, ... administered through the non-adrenergic, non-cholinergic nervous system (branch of the vagal system). ... Substance P and other sensory neuropeptides can be released from the peripheral terminals of sensory nerve fibers in the skin, ...
Skeletal muscle specimens were abnormal in all cases, but myelinated nerve fibers were normal, and in half the patients there ... A sympathetic blocker (alpha adrenergic antagonist), phentolamine, given I.V. has been advocated as a diagnostic test for SMP. ... Spinal cord stimulation (SCS) uses low intensity, electrical impulses to trigger selected nerve fibers along the spinal cord ( ... was a loss of unmyelinated fibers. These findings suggest a microangiopathy in the affected limbs. Thus, patients with RSD/CRPS ...
... adrenergic fibres explanation free. What is adrenergic fibres? Meaning of adrenergic fibres medical term. What does adrenergic ... Looking for online definition of adrenergic fibres in the Medical Dictionary? ... adrenergic fibers. (redirected from adrenergic fibres) ad·re·ner·gic fi·bers. nerve fibers that transmit nervous impulses to ... Synonym(s): adrenergic fibres. ad·re·ner·gic fi·bers. (adrĕ-nĕrjik fībĕrz) Nerve fibers that transmit nervous impulses to ...
Zochodne, Douglas W. ; Low, Phillip A. ; Dyck, Peter J. / Adrenergic sympathectomy ablates unmyelinated fibers in the rat ... Zochodne, D. W., Low, P. A., & Dyck, P. J. (1989). Adrenergic sympathectomy ablates unmyelinated fibers in the rat ... Adrenergic sympathectomy ablates unmyelinated fibers in the rat preganglionic cervical sympathetic trunk. Brain Research. ... Adrenergic sympathectomy ablates unmyelinated fibers in the rat preganglionic cervical sympathetic trunk. / Zochodne, Douglas ...
Adrenergic Fibers / pathology * Adult * Aged * Axons / pathology * Biomarkers * Connective Tissue / pathology * Female ...
ACh-releasing fibers. Cholinergic fibers. sympathetic postganglionic axons that release NE. Adrenergic fibers. ...
Adrenergic Fibers / analysis*. Age Factors. Animals. Animals, Newborn. Catecholamines / analysis*. Cholinergic Fibers. Cornea ...
Adrenergic Fibers / physiology*, ultrastructure. Animals. Atmospheric Pressure*. Ganglia, Sympathetic / physiology*, ...
The cholinergic fibers generally cause contraction, whereas the adrenergic fibers mainly cause inhibition. ... Extrinsic neural afferents to the ENS contain cholinergic and adrenergic fibers. ... The activity of both the cholinergic system and the adrenergic system is 2-3 times that of normal intestine. The cholinergic ( ... excitatory) system is thought to predominate over the adrenergic (inhibitory) system, leading to an increase in smooth muscle ...
... blockade of adrenergic receptors that populate afferent sensory fibers; Site 3) blockade of -adrenergic receptors on the ... adrenergic receptors [6]. It forms covalent bonds with these receptors, which results in a duration of blockade of 8 days or ... T. C. Westfall and D. P. Westfall, "Adrenergic agonists and antagonists," in Goodman and Gilmans, the Pharmacological Basis of ... R. N. Spengler, R. M. Allen, D. G. Remick, R. M. Strieter, and S. L. Kunkel, "Stimulation of α-adrenergic receptor augments the ...
Adrenergic fiber (NE is also called noradrenaline). secretes NE (norepinephrine). Cholinergic fiber. secretes ACH (acetlchorine ... short preganglionic fibers.long postganglionic fibers (thoracolumbar division. NEUROTRANSMITTERS=. Ach secreted by sympathetic ... preganglionic fibers NE secreted by sympathetic postganglionic fibers. ...
β-Adrenergic receptor stimulation with norepinephrine (1 μmol/L) attenuated alternans by 60 [52-65]% [interquartile range] and ... β-adrenergic receptor stimulation with norepinephrine (1 µmol/L) attenuated alternans by 60 [52-65] % [interquartile range] and ... We hypothesize that the border zone is most vulnerable to alternans, that β-adrenergic receptor stimulation can suppresses this ... Simulations also demonstrated that β-adrenergic receptor stimulation in this specific region reduced the formation of ...
ISBN 0-7817-4733-3. Eichbaum FW (1975). "Wavy myocardial fibers in spontaneous and experimental adrenergic cardiopathies". ... one of the earliest changes under a normal microscope are so-called wavy fibers. Subsequently, the myocyte cytoplasm becomes ...
Most postganglionic sympathetic fibers are adrenergic except for sweat glands, thermoregulatory center, arrector pili ...
Adrenergic (C1 and C2) neurons, nerve fibers and presumptive terminal processes. J. Comp. Neurol. 233, 333-349. ... II., Dopaminergic, noradrenergic (A1 and A2) and adrenergic neurons, nerve fibers, and presumptive terminal processes. J. Comp ... Qian, Y., Fritzsch, B., Shirasawa, S., Chen, C. L., Choi, Y., and Ma, Q. (2001). Formation of brainstem (nor)adrenergic centers ... 2007). Origin of climbing fiber neurons and their developmental dependence on Ptf1a. J. Neurosci. 27, 10924-10934. ...
adrenergic fiber. adrenergic receptor. antagonistic effects. cholinergic fiber. cholinergic receptor. collateral ganglia. COMT ... They are called adrenergic fibers because of their release of NE.. b. Parasympathetic pre and postganglionic fibers release Ach ... 2. General Effects of cholinergic and adrenergic fibers.. a. Cholinergic fibers have a generally rapid effect on the body ... 9. Explain the terms: adrenergic fibers, and cholinergic fibers.. 10. Explain why norepinephrines effects on the body are ...
Fibers that release norepinephrine. *Most postganglionic fibers of the sympathetic division are adrenergic, but some are ...
Adrenergic activation modulates the signal from the Reissner fiber to cerebrospinal fluid-contacting neurons during development ... Finally, we study how local adrenergic activation can substitute for the Reissner fiber-signaling pathway to CSF-cNs and rescue ... Our results show that the Reissner fiber acts on CSF-cNs and thereby contributes to establish body axis morphogenesis, and ... Yet, the signaling cascade originating from this fiber to ensure body axis straightening is not understood. Here, we explore ...
Adrenergic activation modulates the signal from the Reissner fiber to cerebrospinal fluid-contacting neurons during development ... Finally, we study how local adrenergic activation can substitute for the Reissner fiber-signaling pathway to CSF-cNs and rescue ... Our results show that the Reissner fiber acts on CSF-cNs and thereby contributes to establish body axis morphogenesis, and ... Yet, the signaling cascade originating from this fiber to ensure body axis straightening is not understood. Here, we explore ...
a-adrenergic tone Adrenergic nerve fibers accompany coronary vessels of any size. The stimulation of cardiac sympathetic nerves ... The role of alpha-adrenergic activity in large and small coronary arteries in man.- 8. Adrenergic control of human coronary ... Alpha-adrenergic receptors and coronary vasospasm.- 11. Enhanced transcardiac 1-norepinephrine response during cold pressor ... Thus, the primary effect of sympathetic stimulation on the coronary arteries is the alpha-adrenergic mediated vasoconstriction ...
cutaneous vessels are innervated by sympathetic adrenergic vasoconstrictor fibers; vasodilation is an important mechanism for ...
In both mice and humans, adrenergic nerve fibers were denser in p53-deficient oral tumor tissue. ... and surrounded by fewer adrenergic-like neurons. On the other hand, human patients with higher densities of adrenergic neurons ... Adrenergic nerves can trigger the bodys "fight-or-flight" response by releasing stimulating chemical messengers. Previous work ... Consistent with this idea, when the researchers blocked adrenergic signaling in mice, either by disabling sensory nerves or ...
15th Dec 2001 Medline: Adrenergic Nerve Fibers In Thymus During Immune Response 15th Dec 2001 Medline: HLA Gene In MS In ...
Nerve fibers that secrete acetylcholine are called cholinergic fibers. Fibers that secrete norepinephrine are called adrenergic ... The role of cholinergic and adrenergic fibers continues to be studied in dysautonomia research and particularly the role they ... fibers. Generally, acetylcholine has parasympathetic (inhibiting) effects and norepinephrine has sympathetic (stimulating) ...
The results obtained support the hypothesis that both NE and 5-HT coexist in the nerve vesicles of pineal adrenergic fibers. ... Both drugs deplete the pool of pineal 5-hydroxytryptamine (5-HT) localized in the adrenergic fibers which innervate the gland. ... ULTRASTRUCTURAL CYTOCHEMISTRY AND PHARMACOLOGY OF 5-HYDROXYTRYPTAMINE IN ADRENERGIC NERVE ENDINGS. III. SELECTIVE INCREASE OF ... ULTRASTRUCTURAL CYTOCHEMISTRY AND PHARMACOLOGY OF 5-HYDROXYTRYPTAMINE IN ADRENERGIC NERVE ENDINGS. III. SELECTIVE INCREASE OF ...
Dopaminergic, noradrenergic (A1 and A2) and adrenergic neurons, nerve fibers, and presumptive terminal processes. J Comp Neurol ... 1999) The origin of catecholaminergic nerve fibers in the subdiaphragmatic vagus nerve of the rat. J Auton Nerv Syst 76:108-117 ... In fact, adrenergic blockade with α- or β-adrenoceptor antagonists did not seem to affect the relaxatory or contractile ... Our data thus suggest that the origin of the adrenergic modulation of ACh release from vagal terminals must be found in areas ...
  • Although the acute actions of short-acting β(2)-adrenoceptor agonists on force production in isolated mammalian skeletal muscle fibers have been the subject of a number of previous studies, those of long-acting β(2)-adrenoceptor agonists have never been investigated. (nih.gov)
  • In summary, long- and short-acting β(2)-adrenoceptor agonists have opposite effects on force production in isolated intact mouse skeletal muscle fiber bundles. (nih.gov)
  • We conclude that α-adrenergic agonists inhibit volume-sensitive Cl − currents in rabbit atrial cells by interacting with an α 1A -adrenoceptor mechanism that is coupled to PKC via a PTX-sensitive G protein. (ahajournals.org)
  • β2-adrenergic agonists are also known to promote lipolysis and increase muscle mass in many species [ 2 - 8 ]. (biomedcentral.com)
  • This repartitioning effect and improvement in muscle growth efficiency has led to the addition of β2-adrenergic agonists such as ractopamine and zilpaterol to feed products for production animals. (biomedcentral.com)
  • The present study is to find the fascicular pattern of radial nerve (at antecubital fossa), microanatomic morphometric characteristics of its connective tissue components and changes with age and study of intraneural sympathetic fiber content. (elsevier.com)
  • ProAir Digihaler ProAir Digihaler (albuterol sulfate) is a beta2-adrenergic agonist indicated. (drugs.com)
  • According to the myogenic theory, the primary damage to the cardiac muscle fibers is triggered by humoral or cell-mediated immune factors (8). (fac.org.ar)
  • In 1924, Monckeberg (12) observed pronounced lesions in the autonomic ganglia and cardiac nerve fibers of experimentally infected dogs. (fac.org.ar)
  • The idea of a neurotoxin was inspired by the work of Vianna (10) and Monckeberg (12), who had described the destruction in canine models of nonparasitized cells subsequent to the rupture of nearby nests, as well as promounced lesions in the autonomic ganglia and cardiac nervous fibers. (fac.org.ar)
  • Our objective in this study was to evaluate the correlation between C-fiber involvement as shown by skin biopsy and adrenergic cardiac metaiodobenzylguanadine (MIBG) uptake in POTS patients. (wiley.com)
  • Background: We previously found a severe impairment of cardiac uptake of I-metaiodobenzylguanidine (MIBG), an analogue of norepinephrine, on myocardial scintigraphy in a small group of patients with cardiac syndrome X (CSX), suggesting a dysfunction of cardiac adrenergic nerve fibres. (elsevier.com)
  • Conclusion: Our data show a relevant impairment of cardiac MIBG uptake in patients with CSX, suggesting that functional abnormalities in cardiac adrenergic nerve function may play a significant role in the mechanisms responsible for the syndrome. (elsevier.com)
  • Cardiac adrenergic nerve function in patients with cardiac syndrome X . Journal of Cardiovascular Medicine , 11 (3), 151-156. (elsevier.com)
  • A nerve fiber of the autonomic nervous system that terminates in smooth or cardiac muscle or in a gland. (unboundmedicine.com)
  • These results suggest a potentially novel mechanism of α-adrenergic control of cardiac electrical activity, the inhibition of volume-sensitive Cl − currents, and indicate that PKC, well known to elicit phosphorylation-dependent Cl − currents in cat and guinea pig ventricular myocytes, is also capable of potently inhibiting other forms of cardiac Cl − current. (ahajournals.org)
  • The intracardiac pathways carrying the cardiovascular reflex responses mediated by cardiac sympathetic and vagal afferent fibers were examined in this study. (elsevier.com)
  • Preventing maladaptive alterations of Ca 2+ cycling proteins represents a novel mechanism for XO inhibition-mediated preservation of cardiac function in HF, raising the possibility that anti-oxidant therapies for HF may ameliorate transcriptional changes associated with adverse cardiac remodeling and β-adrenergic hyporesponsiveness. (physiology.org)
  • Adrenergic nerves can trigger the body's "fight-or-flight" response by releasing stimulating chemical messengers. (nih.gov)
  • Three sets of peripheral nerves are involved in penile erection and subsequent detumescence: parasympathetic nerves from the second to fourth sacral (S2-S4) segments, sympathetic nerves from the tenth thoracic to the second lumbar (T10-L2) thoracolumbar outflow, and somatic fibers via the pudendal nerves (Figure 14). (amazonaws.com)
  • Groups of myelinated fibers fan out in a horizontal plane to form a branching network from which fibers ascend, usually accompanying blood vessels, to form a mesh of interlacing nerves in the superficial dermis. (telemedicine.org)
  • releasing epinephrine or a similar substance [the adrenergic nerves of the sympathetic nervous system] 2. (academic.ru)
  • Methods: Twenty human (21-87 years) cadaveric radial nerves have been collected from antecubital fossa and the study has been performed at magnifications (10×, 20× and 40× objective) after routine histological (hematoxylin & eosin stain) processing was done for morphometric analysis (total cross-sectional, fascicular and non-fascicular area) and immunohistochemical (tyrosine hydroxylase) processing for sympathetic fibers. (elsevier.com)
  • 17. Compare the contractions of smooth and skeletal muscle fibers with regard to speed of contraction and relaxation, ability to contract when greatly stretched, energy required for a sustained contraction, and resistance to fatigue. (cuny.edu)
  • These data suggest that sympathetic afferent fibers travel in the superficial subepicardium in an apex-to-base direction. (elsevier.com)
  • Vagal afferent fibers travel deeper in the myocardium until they approach the atrioventricular groove, where they ascend to the superficial subepicardium. (elsevier.com)
  • There is sound experimental evidence that cardiovascular sympathetic afferent fibers mediate cardiovascular reflexes largely excitatory in nature with positive-feedback characteristics. (elsevier.com)
  • In each experiment, the pressor response to tyramine (250 μg/kg iv) was significantly attenuated in 6OHDA-treated rats, thereby confirming that 6OHDA treatment destroyed sympathetic catecholaminergic fibers. (elsevier.com)
  • Collectively, these findings suggest that catecholaminergic fibers located outside the blood-brain barrier contribute to VP and OT secretion during hemorrhage and arterial hypotension. (elsevier.com)
  • Observational Study in Patients Suffering From Benign Prostatic Hyperplasia Treated With Alpha - adrenergic Blockade Observational Study in Patients Suffering From Benign Prostatic Hyperplasia Treated With Alpha - adrenergic Blockade - Full Text View - ClinicalTrials.gov Hide glossary Glossary Study record managers: refer to the if submitting registration or results information. (tripdatabase.com)
  • Recent work suggests that newly formed nerve fibers may regulate the tumor microenvironment, but their exact functions are unclear. (ovid.com)
  • Previous studies have demonstrated that catecholaminergic, tyrosine hydroxylase (TH)-immunoreactive (IR) perikarya and fibers are widely distributed in the human hypothalamus. (luriechildrens.org)
  • The up-regulation of synaptic strength is mediated by the activity-dependent modulation by β-adrenergic transmission. (pnas.org)
  • Because the CA3-CA1 and the CA1-SB synaptic pathways are in series and the β-adrenergic modulation is region-specific, this modulation seems to be involved in the selective control of signal transmission between the different regions of hippocampus. (pnas.org)
  • The present experiments were designed to assess the potential α-adrenergic modulation of I Cl.swell in rabbit atrial myocytes. (ahajournals.org)
  • However, the current consensus on the etiology of CRPS favors an interpretation of the symptomatology as an evidence of decreased sympathetic activity to the injured limb and a resulting upregulation of adrenergic sensitivity. (hindawi.com)
  • β2- Adrenergic Receptor-Mediated HIF-1α Upregulation Mediates Blood Brain Barrier Damage in Acute Cerebral Ischemia Disruption of the blood brain barrier (BBB) within the thrombolytic time window is an antecedent event to intracerebral hemorrhage in ischemic stroke. (tripdatabase.com)