Cell membrane glycoproteins that are selectively permeable to potassium ions. At least eight major groups of K channels exist and they are made up of dozens of different subunits.
A major class of calcium-activated potassium channels that are found primarily in excitable CELLS. They play important roles in the transmission of ACTION POTENTIALS and generate a long-lasting hyperpolarization known as the slow afterhyperpolarization.
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.
A class of drugs that act by inhibition of potassium efflux through cell membranes. Blockade of potassium channels prolongs the duration of ACTION POTENTIALS. They are used as ANTI-ARRHYTHMIA AGENTS and VASODILATOR AGENTS.
Potassium channels where the flow of K+ ions into the cell is greater than the outward flow.
Gated, ion-selective glycoproteins that traverse membranes. The stimulus for ION CHANNEL GATING can be due to a variety of stimuli such as LIGANDS, a TRANSMEMBRANE POTENTIAL DIFFERENCE, mechanical deformation or through INTRACELLULAR SIGNALING PEPTIDES AND PROTEINS.
Potassium channel whose permeability to ions is extremely sensitive to the transmembrane potential difference. The opening of these channels is induced by the membrane depolarization of the ACTION POTENTIAL.
Potassium channels whose activation is dependent on intracellular calcium concentrations.
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.
Voltage-gated potassium channels whose primary subunits contain six transmembrane segments and form tetramers to create a pore with a voltage sensor. They are related to their founding member, shaker protein, Drosophila.
The opening and closing of ion channels due to a stimulus. The stimulus can be a change in membrane potential (voltage-gated), drugs or chemical transmitters (ligand-gated), or a mechanical deformation. Gating is thought to involve conformational changes of the ion channel which alters selective permeability.
A highly neurotoxic polypeptide from the venom of the honey bee (Apis mellifera). It consists of 18 amino acids with two disulfide bridges and causes hyperexcitability resulting in convulsions and respiratory paralysis.
A delayed rectifier subtype of shaker potassium channels that is the predominant VOLTAGE-GATED POTASSIUM CHANNEL of T-LYMPHOCYTES.
A delayed rectifier subtype of shaker potassium channels that is selectively inhibited by a variety of SCORPION VENOMS.
A delayed rectifier subtype of shaker potassium channels that is commonly mutated in human episodic ATAXIA and MYOKYMIA.
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 family of voltage-gated potassium channels that are characterized by long N-terminal and C-terminal intracellular tails. They are named from the Drosophila protein whose mutation causes abnormal leg shaking under ether anesthesia. Their activation kinetics are dependent on extracellular MAGNESIUM and PROTON concentration.
A major class of calcium activated potassium channels whose members are voltage-dependent. MaxiK channels are activated by either membrane depolarization or an increase in intracellular Ca(2+). They are key regulators of calcium and electrical signaling in a variety of tissues.
A shaker subfamily that is prominently expressed in NEURONS and are necessary for high-frequency, repetitive firing of ACTION POTENTIALS.
A voltage-gated potassium channel that is expressed primarily in the HEART.
An electrophysiologic technique for studying cells, cell membranes, and occasionally isolated organelles. All patch-clamp methods rely on a very high-resistance seal between a micropipette and a membrane; the seal is usually attained by gentle suction. The four most common variants include on-cell patch, inside-out patch, outside-out patch, and whole-cell clamp. Patch-clamp methods are commonly used to voltage clamp, that is control the voltage across the membrane and measure current flow, but current-clamp methods, in which the current is controlled and the voltage is measured, are also used.
The ability of a substrate to allow the passage of ELECTRONS.
A major class of calcium-activated potassium channels that were originally discovered in ERYTHROCYTES. They are found primarily in non-excitable CELLS and set up electrical gradients for PASSIVE ION TRANSPORT.
A family of delayed rectifier voltage-gated potassium channels that share homology with their founding member, KCNQ1 PROTEIN. KCNQ potassium channels have been implicated in a variety of diseases including LONG QT SYNDROME; DEAFNESS; and EPILEPSY.
A delayed rectifier subtype of shaker potassium channels that conducts a delayed rectifier current. It contributes to ACTION POTENTIAL repolarization of MYOCYTES in HEART ATRIA.
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.
A subfamily of shaker potassium channels that shares homology with its founding member, Shab protein, Drosophila. They regulate delayed rectifier currents in the NERVOUS SYSTEM of DROSOPHILA and in the SKELETAL MUSCLE and HEART of VERTEBRATES.
A fast inactivating subtype of shaker potassium channels that contains two inactivation domains at its N terminus.
Cell membrane glycoproteins that form channels to selectively pass chloride ions. Nonselective blockers include FENAMATES; ETHACRYNIC ACID; and TAMOXIFEN.
Heteromultimers of Kir6 channels (the pore portion) and sulfonylurea receptor (the regulatory portion) which affect function of the HEART; PANCREATIC BETA CELLS; and KIDNEY COLLECTING DUCTS. KATP channel blockers include GLIBENCLAMIDE and mitiglinide whereas openers include CROMAKALIM and minoxidil sulfate.
A very slow opening and closing voltage-gated potassium channel that is expressed in NEURONS and is commonly mutated in BENIGN FAMILIAL NEONATAL CONVULSIONS.
Potassium channels that contain two pores in tandem. They are responsible for baseline or leak currents and may be the most numerous of all K channels.
A potassium-selective ion channel blocker. (From J Gen Phys 1994;104(1):173-90)
A 37-amino acid residue peptide isolated from the scorpion Leiurus quinquestriatus hebraeus. It is a neurotoxin that inhibits calcium activated potassium channels.
A very slow opening and closing voltage-gated potassium channel that is expressed in NEURONS and is closely related to KCNQ2 POTASSIUM CHANNEL. It is commonly mutated in BENIGN FAMILIAL NEONATAL CONVULSIONS.
A shaker subfamily of potassium channels that participate in transient outward potassium currents by activating at subthreshold MEMBRANE POTENTIALS, inactivating rapidly, and recovering from inactivation quickly.
An antidiabetic sulfonylurea derivative with actions similar to those of chlorpropamide.
A class of drugs that act by selective inhibition of calcium influx through cellular membranes.
A family of inwardly-rectifying potassium channels that are activated by PERTUSSIS TOXIN sensitive G-PROTEIN-COUPLED RECEPTORS. GIRK potassium channels are primarily activated by the complex of GTP-BINDING PROTEIN BETA SUBUNITS and GTP-BINDING PROTEIN GAMMA SUBUNITS.
Venoms from animals of the order Scorpionida of the class Arachnida. They contain neuro- and hemotoxins, enzymes, and various other factors that may release acetylcholine and catecholamines from nerve endings. Of the several protein toxins that have been characterized, most are immunogenic.
A group of slow opening and closing voltage-gated potassium channels. Because of their delayed activation kinetics they play an important role in controlling ACTION POTENTIAL duration.
Long-lasting voltage-gated CALCIUM CHANNELS found in both excitable and nonexcitable tissue. They are responsible for normal myocardial and vascular smooth muscle contractility. Five subunits (alpha-1, alpha-2, beta, gamma, and delta) make up the L-type channel. The alpha-1 subunit is the binding site for calcium-based antagonists. Dihydropyridine-based calcium antagonists are used as markers for these binding sites.
Female germ cells derived from OOGONIA and termed OOCYTES when they enter MEIOSIS. The primary oocytes begin meiosis but are arrested at the diplotene state until OVULATION at PUBERTY to give rise to haploid secondary oocytes or ova (OVUM).
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.
Abrupt changes in the membrane potential that sweep along the CELL MEMBRANE of excitable cells in response to excitation stimuli.
The commonest and widest ranging species of the clawed "frog" (Xenopus) in Africa. This species is used extensively in research. There is now a significant population in California derived from escaped laboratory animals.
Agents that increase calcium influx into calcium channels of excitable tissues. This causes vasoconstriction in VASCULAR SMOOTH MUSCLE and/or CARDIAC MUSCLE cells as well as stimulation of insulin release from pancreatic islets. Therefore, tissue-selective calcium agonists have the potential to combat cardiac failure and endocrinological disorders. They have been used primarily in experimental studies in cell and tissue culture.
An element of the alkaline earth group of metals. It has an atomic symbol Ba, atomic number 56, and atomic weight 138. All of its acid-soluble salts are poisonous.
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.
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.
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.
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.
A member of the alkali group of metals. It has the atomic symbol Na, atomic number 11, and atomic weight 23.
One of the POTASSIUM CHANNEL BLOCKERS, with secondary effect on calcium currents, which is used mainly as a research tool and to characterize channel subtypes.
An aquatic genus of the family, Pipidae, occurring in Africa and distinguished by having black horny claws on three inner hind toes.
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.
The pore-forming subunits of large-conductance calcium-activated potassium channels. They form tetramers in CELL MEMBRANES.
The relationship between the dose of an administered drug and the response of the organism to the drug.
A topical bacteriostat that is available as various salts. It is used in wound dressings and mouth infections and may also have antifungal action, but may cause skin ulceration.
Inorganic compounds derived from hydrochloric acid that contain the Cl- ion.
The rate dynamics in chemical or physical systems.
Arthropods of the order Scorpiones, of which 1500 to 2000 species have been described. The most common live in tropical or subtropical areas. They are nocturnal and feed principally on insects and other arthropods. They are large arachnids but do not attack man spontaneously. They have a venomous sting. Their medical significance varies considerably and is dependent on their habits and venom potency rather than on their size. At most, the sting is equivalent to that of a hornet but certain species possess a highly toxic venom potentially fatal to humans. (From Dorland, 27th ed; Smith, Insects and Other Arthropods of Medical Importance, 1973, p417; Barnes, Invertebrate Zoology, 5th ed, p503)
The lipid- and protein-containing, selectively permeable membrane that surrounds the cytoplasm in prokaryotic and eukaryotic cells.
CALCIUM CHANNELS that are concentrated in neural tissue. Omega toxins inhibit the actions of these channels by altering their voltage dependence.
A class of drugs that act by inhibition of sodium influx through cell membranes. Blockade of sodium channels slows the rate and amplitude of initial rapid depolarization, reduces cell excitability, and reduces conduction velocity.
A potassium-channel opening vasodilator that has been investigated in the management of hypertension. It has also been tried in patients with asthma. (Martindale, The Extra Pharmacopoeia, 30th ed, p352)
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.
A guanidine that opens POTASSIUM CHANNELS producing direct peripheral vasodilatation of the ARTERIOLES. It reduces BLOOD PRESSURE and peripheral resistance and produces fluid retention. (Martindale The Extra Pharmacopoeia, 31st ed)
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.
Potassium or potassium compounds used in foods or as foods.
ATP-BINDING CASSETTE PROTEINS that are highly conserved and widely expressed in nature. They form an integral part of the ATP-sensitive potassium channel complex which has two intracellular nucleotide folds that bind to sulfonylureas and their analogs.
Inorganic compounds that contain barium as an integral part of the molecule.
The movement of ions across energy-transducing cell membranes. Transport can be active, passive or facilitated. Ions may travel by themselves (uniport), or as a group of two or more ions in the same (symport) or opposite (antiport) directions.
Established cell cultures that have the potential to propagate indefinitely.
Models used experimentally or theoretically to study molecular shape, electronic properties, or interactions; includes analogous molecules, computer-generated graphics, and mechanical structures.
A member of the alkali metals. It has an atomic symbol Cs, atomic number 50, and atomic weight 132.91. Cesium has many industrial applications, including the construction of atomic clocks based on its atomic vibrational frequency.
A condition due to decreased dietary intake of potassium, as in starvation or failure to administer in intravenous solutions, or to gastrointestinal loss in diarrhea, chronic laxative abuse, vomiting, gastric suction, or bowel diversion. Severe potassium deficiency may produce muscular weakness and lead to paralysis and respiratory failure. Muscular malfunction may result in hypoventilation, paralytic ileus, hypotension, muscle twitches, tetany, and rhabomyolysis. Nephropathy from potassium deficit impairs the concentrating mechanism, producing POLYURIA and decreased maximal urinary concentrating ability with secondary POLYDIPSIA. (Merck Manual, 16th ed)
Compounds that contain the radical R2C=N.OH derived from condensation of ALDEHYDES or KETONES with HYDROXYLAMINE. Members of this group are CHOLINESTERASE REACTIVATORS.
A subgroup of TRP cation channels that contain 3-4 ANKYRIN REPEAT DOMAINS and a conserved C-terminal domain. Members are highly expressed in the CENTRAL NERVOUS SYSTEM. Selectivity for calcium over sodium ranges from 0.5 to 10.
A chloride channel that regulates secretion in many exocrine tissues. Abnormalities in the CFTR gene have been shown to cause cystic fibrosis. (Hum Genet 1994;93(4):364-8)
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.
A subgroup of cyclic nucleotide-regulated ION CHANNELS within the superfamily of pore-loop cation channels. They are expressed in OLFACTORY NERVE cilia and in PHOTORECEPTOR CELLS and some PLANTS.
A suspected industrial carcinogen (and listed as such by OSHA). Its N-hydroxy metabolite is strongly carcinogenic and mutagenic.
A strain of albino rat developed at the Wistar Institute that has spread widely at other institutions. This has markedly diluted the original strain.
Inorganic compounds that contain potassium as an integral part of the molecule.
A heterogenous group of transient or low voltage activated type CALCIUM CHANNELS. They are found in cardiac myocyte membranes, the sinoatrial node, Purkinje cells of the heart and the central nervous system.
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 regulatory subunits of large-conductance calcium-activated potassium channels.
Compounds with a core of fused benzo-pyran rings.
Use of electric potential or currents to elicit biological responses.
Any detectable and heritable change in the genetic material that causes a change in the GENOTYPE and which is transmitted to daughter cells and to succeeding generations.
Proteins that bind specific drugs with high affinity and trigger intracellular changes influencing the behavior of cells. Drug receptors are generally thought to be receptors for some endogenous substance not otherwise specified.
Elements of limited time intervals, contributing to particular results or situations.
Sodium channels found on salt-reabsorbing EPITHELIAL CELLS that line the distal NEPHRON; the distal COLON; SALIVARY DUCTS; SWEAT GLANDS; and the LUNG. They are AMILORIDE-sensitive and play a critical role in the control of sodium balance, BLOOD VOLUME, and BLOOD PRESSURE.
The level of protein structure in which combinations of secondary protein structures (alpha helices, beta sheets, loop regions, and motifs) pack together to form folded shapes called domains. Disulfide bridges between cysteines in two different parts of the polypeptide chain along with other interactions between the chains play a role in the formation and stabilization of tertiary structure. Small proteins usually consist of only one domain but larger proteins may contain a number of domains connected by segments of polypeptide chain which lack regular secondary structure.
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.
Single chains of amino acids that are the units of multimeric PROTEINS. Multimeric proteins can be composed of identical or non-identical subunits. One or more monomeric subunits may compose a protomer which itself is a subunit structure of a larger assembly.
Layers of lipid molecules which are two molecules thick. Bilayer systems are frequently studied as models of biological membranes.
A derivative of the NIACINAMIDE that is structurally combined with an organic nitrate. It is a potassium-channel opener that causes vasodilatation of arterioles and large coronary arteries. Its nitrate-like properties produce venous vasodilation through stimulation of guanylate cyclase.
Venoms from snakes of the family Elapidae, including cobras, kraits, mambas, coral, tiger, and Australian snakes. The venoms contain polypeptide toxins of various kinds, cytolytic, hemolytic, and neurotoxic factors, but fewer enzymes than viper or crotalid venoms. Many of the toxins have been characterized.
Toxic substances from microorganisms, plants or animals that interfere with the functions of the nervous system. Most venoms contain neurotoxic substances. Myotoxins are included in this concept.
A subgroup of TRP cation channels named after vanilloid receptor. They are very sensitive to TEMPERATURE and hot spicy food and CAPSAICIN. They have the TRP domain and ANKYRIN repeats. Selectivity for CALCIUM over SODIUM ranges from 3 to 100 fold.
A family of proton-gated sodium channels that are primarily expressed in neuronal tissue. They are AMILORIDE-sensitive and are implicated in the signaling of a variety of neurological stimuli, most notably that of pain in response to acidic conditions.
A benzothiadiazine derivative that is a peripheral vasodilator used for hypertensive emergencies. It lacks diuretic effect, apparently because it lacks a sulfonamide group.
Drugs used to cause dilation of the blood vessels.
A subgroup of TRP cation channels named after melastatin protein. They have the TRP domain but lack ANKYRIN repeats. Enzyme domains in the C-terminus leads to them being called chanzymes.
The process by which cells convert mechanical stimuli into a chemical response. It can occur in both cells specialized for sensing mechanical cues such as MECHANORECEPTORS, and in parenchymal cells whose primary function is not mechanosensory.
The physiological widening of BLOOD VESSELS by relaxing the underlying VASCULAR SMOOTH MUSCLE.
An element that is an alkali metal. It has an atomic symbol Rb, atomic number 37, and atomic weight 85.47. It is used as a chemical reagent and in the manufacture of photoelectric cells.
Stable potassium atoms that have the same atomic number as the element potassium, but differ in atomic weight. K-41 is a stable potassium isotope.
The normality of a solution with respect to HYDROGEN ions; H+. It is related to acidity measurements in most cases by pH = log 1/2[1/(H+)], where (H+) is the hydrogen ion concentration in gram equivalents per liter of solution. (McGraw-Hill Dictionary of Scientific and Technical Terms, 6th ed)
The characteristic 3-dimensional shape of a protein, including the secondary, supersecondary (motifs), tertiary (domains) and quaternary structure of the peptide chain. PROTEIN STRUCTURE, QUATERNARY describes the conformation assumed by multimeric proteins (aggregates of more than one polypeptide chain).
Members of the class of compounds composed of AMINO ACIDS joined together by peptide bonds between adjacent amino acids into linear, branched or cyclical structures. OLIGOPEPTIDES are composed of approximately 2-12 amino acids. Polypeptides are composed of approximately 13 or more amino acids. PROTEINS are linear polypeptides that are normally synthesized on RIBOSOMES.
Calcium compounds used as food supplements or in food to supply the body with calcium. Dietary calcium is needed during growth for bone development and for maintenance of skeletal integrity later in life to prevent osteoporosis.
10-carbon saturated monocarboxylic acids.
Organic compounds containing both the hydroxyl and carboxyl radicals.
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.
A quality of cell membranes which permits the passage of solvents and solutes into and out of cells.
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.
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 delayed rectifier subtype of shaker potassium channels that has been described in NEURONS and ASTROCYTES.
Unstable isotopes of potassium that decay or disintegrate emitting radiation. K atoms with atomic weights 37, 38, 40, and 42-45 are radioactive potassium isotopes.
CELL LINE derived from the ovary of the Chinese hamster, Cricetulus griseus (CRICETULUS). The species is a favorite for cytogenetic studies because of its small chromosome number. The cell line has provided model systems for the study of genetic alterations in cultured mammalian cells.
An atom or group of atoms that have a positive or negative electric charge due to a gain (negative charge) or loss (positive charge) of one or more electrons. Atoms with a positive charge are known as CATIONS; those with a negative charge are ANIONS.
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.
The degree of similarity between sequences of amino acids. This information is useful for the analyzing genetic relatedness of proteins and species.
Positively charged atoms, radicals or groups of atoms which travel to the cathode or negative pole during electrolysis.
A metallic element that has the atomic symbol Mg, atomic number 12, and atomic weight 24.31. It is important for the activity of many enzymes, especially those involved in OXIDATIVE PHOSPHORYLATION.
The uptake of naked or purified DNA by CELLS, usually meaning the process as it occurs in eukaryotic cells. It is analogous to bacterial transformation (TRANSFORMATION, BACTERIAL) and both are routinely employed in GENE TRANSFER TECHNIQUES.
Compounds with a BENZENE fused to IMIDAZOLES.
A subfamily in the family MURIDAE, comprising the hamsters. Four of the more common genera are Cricetus, CRICETULUS; MESOCRICETUS; and PHODOPUS.
A superorder of CEPHALOPODS comprised of squid, cuttlefish, and their relatives. Their distinguishing feature is the modification of their fourth pair of arms into tentacles, resulting in 10 limbs.
A curved elevation of GRAY MATTER extending the entire length of the floor of the TEMPORAL HORN of the LATERAL VENTRICLE (see also TEMPORAL LOBE). The hippocampus proper, subiculum, and DENTATE GYRUS constitute the hippocampal formation. Sometimes authors include the ENTORHINAL CORTEX in the hippocampal formation.
CALCIUM CHANNELS located within the PURKINJE CELLS of the cerebellum. They are involved in stimulation-secretion coupling of neurons.
Pyridines substituted in any position with an amino group. May be hydrogenated, but must retain at least one double bond.
The study of PHYSICAL PHENOMENA and PHYSICAL PROCESSES as applied to living things.
A potent vasodilator agent with calcium antagonistic action. It is a useful anti-anginal agent that also lowers blood pressure.
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.
A family of neuronal calcium-sensor proteins that interact with and regulate potassium channels, type A.
The parts of a macromolecule that directly participate in its specific combination with another molecule.
A cell line generated from human embryonic kidney cells that were transformed with human adenovirus type 5.
The hollow, muscular organ that maintains the circulation of the blood.
Genetically engineered MUTAGENESIS at a specific site in the DNA molecule that introduces a base substitution, or an insertion or deletion.
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.
A broad group of eukaryotic six-transmembrane cation channels that are classified by sequence homology because their functional involvement with SENSATION is varied. They have only weak voltage sensitivity and ion selectivity. They are named after a DROSOPHILA mutant that displayed transient receptor potentials in response to light. A 25-amino-acid motif containing a TRP box (EWKFAR) just C-terminal to S6 is found in TRPC, TRPV and TRPM subgroups. ANKYRIN repeats are found in TRPC, TRPV & TRPN subgroups. Some are functionally associated with TYROSINE KINASE or TYPE C PHOSPHOLIPASES.
A condition that is characterized by episodes of fainting (SYNCOPE) and varying degree of ventricular arrhythmia as indicated by the prolonged QT interval. The inherited forms are caused by mutation of genes encoding cardiac ion channel proteins. The two major forms are ROMANO-WARD SYNDROME and JERVELL-LANGE NIELSEN SYNDROME.
An actinomycete used for production of commercial ANTIBIOTICS and as a host for gene cloning.
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.
CALCIUM CHANNELS located in the neurons of the brain.
A subgroup of cyclic nucleotide-regulated ION CHANNELS of the superfamily of pore-loop cation channels that are opened by hyperpolarization rather than depolarization. The ion conducting pore passes SODIUM, CALCIUM, and POTASSIUM cations with a preference for potassium.
Proteins prepared by recombinant DNA technology.
The physical characteristics and processes of biological systems.
The generic name for the group of aliphatic hydrocarbons Cn-H2n+2. They are denoted by the suffix -ane. (Grant & Hackh's Chemical Dictionary, 5th ed)
Membrane proteins whose primary function is to facilitate the transport of positively charged molecules (cations) across a biological membrane.
The nonstriated involuntary muscle tissue of blood vessels.
Derivatives of ammonium compounds, NH4+ Y-, in which all four of the hydrogens bonded to nitrogen have been replaced with hydrocarbyl groups. These are distinguished from IMINES which are RN=CR2.
An optical isomer of quinine, extracted from the bark of the CHINCHONA tree and similar plant species. This alkaloid dampens the excitability of cardiac and skeletal muscles by blocking sodium and potassium currents across cellular membranes. It prolongs cellular ACTION POTENTIALS, and decreases automaticity. Quinidine also blocks muscarinic and alpha-adrenergic neurotransmission.
A group of compounds that are monomethyl derivatives of pyridines. (From Dorland, 28th ed)
Synthetic transcripts of a specific DNA molecule or fragment, made by an in vitro transcription system. This cRNA can be labeled with radioactive uracil and then used as a probe. (King & Stansfield, A Dictionary of Genetics, 4th ed)
A potent direct-acting peripheral vasodilator (VASODILATOR AGENTS) that reduces peripheral resistance and produces a fall in BLOOD PRESSURE. (From Martindale, The Extra Pharmacopoeia, 30th ed, p371)
Proteins which are found in membranes including cellular and intracellular membranes. They consist of two types, peripheral and integral proteins. They include most membrane-associated enzymes, antigenic proteins, transport proteins, and drug, hormone, and lectin receptors.
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.
A family of MEMBRANE TRANSPORT PROTEINS that require ATP hydrolysis for the transport of substrates across membranes. The protein family derives its name from the ATP-binding domain found on the protein.
A heat-stable, low-molecular-weight activator protein found mainly in the brain and heart. The binding of calcium ions to this protein allows this protein to bind to cyclic nucleotide phosphodiesterases and to adenyl cyclase with subsequent activation. Thereby this protein modulates cyclic AMP and cyclic GMP levels.
The process in which substances, either endogenous or exogenous, bind to proteins, peptides, enzymes, protein precursors, or allied compounds. Specific protein-binding measures are often used as assays in diagnostic assessments.
Abnormally low potassium concentration in the blood. It may result from potassium loss by renal secretion or by the gastrointestinal route, as by vomiting or diarrhea. It may be manifested clinically by neuromuscular disorders ranging from weakness to paralysis, by electrocardiographic abnormalities (depression of the T wave and elevation of the U wave), by renal disease, and by gastrointestinal disorders. (Dorland, 27th ed)
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 relationship between the chemical structure of a compound and its biological or pharmacological activity. Compounds are often classed together because they have structural characteristics in common including shape, size, stereochemical arrangement, and distribution of functional groups.
Positively charged atoms, radicals or group of atoms with a valence of plus 1, which travel to the cathode or negative pole during electrolysis.
A sulphonylurea hypoglycemic agent with actions and uses similar to those of CHLORPROPAMIDE. (From Martindale, The Extra Pharmacopoeia, 30th ed, p290)
Nerve fibers that are capable of rapidly conducting impulses away from the neuron cell body.
An inorganic compound that is used as a source of iodine in thyrotoxic crisis and in the preparation of thyrotoxic patients for thyroidectomy. (From Dorland, 27th ed)
Pyridine moieties which are partially saturated by the addition of two hydrogen atoms in any position.
Agents used for the treatment or prevention of cardiac arrhythmias. They may affect the polarization-repolarization phase of the action potential, its excitability or refractoriness, or impulse conduction or membrane responsiveness within cardiac fibers. Anti-arrhythmia agents are often classed into four main groups according to their mechanism of action: sodium channel blockade, beta-adrenergic blockade, repolarization prolongation, or calcium channel blockade.
CALCIUM CHANNELS located in the neurons of the brain. They are inhibited by the marine snail toxin, omega conotoxin MVIIC.
Venoms from jellyfish; CORALS; SEA ANEMONES; etc. They contain hemo-, cardio-, dermo- , and neuro-toxic substances and probably ENZYMES. They include palytoxin, sarcophine, and anthopleurine.
A voltage-gated sodium channel subtype that mediates the sodium ion PERMEABILITY of CARDIOMYOCYTES. Defects in the SCN5A gene, which codes for the alpha subunit of this sodium channel, are associated with a variety of CARDIAC DISEASES that result from loss of sodium channel function.
Negatively charged atoms, radicals or groups of atoms which travel to the anode or positive pole during electrolysis.
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.
Property of membranes and other structures to permit passage of light, heat, gases, liquids, metabolites, and mineral ions.
A genus of the family Muridae consisting of eleven species. C. migratorius, the grey or Armenian hamster, and C. griseus, the Chinese hamster, are the two species used in biomedical research.
Unstable isotopes of rubidium that decay or disintegrate emitting radiation. Rb atoms with atomic weights 79-84, and 86-95 are radioactive rubidium isotopes.
Body organ that filters blood for the secretion of URINE and that regulates ion concentrations.
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 insertion of recombinant DNA molecules from prokaryotic and/or eukaryotic sources into a replicating vehicle, such as a plasmid or virus vector, and the introduction of the resultant hybrid molecules into recipient cells without altering the viability of those cells.
Carbonic acid calcium salt (CaCO3). An odorless, tasteless powder or crystal that occurs in nature. It is used therapeutically as a phosphate buffer in hemodialysis patients and as a calcium supplement.
Interstitial space between cells, occupied by INTERSTITIAL FLUID as well as amorphous and fibrous substances. For organisms with a CELL WALL, the extracellular space includes everything outside of the CELL MEMBRANE including the PERIPLASM and the cell wall.
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.
The level of protein structure in which regular hydrogen-bond interactions within contiguous stretches of polypeptide chain give rise to alpha helices, beta strands (which align to form beta sheets) or other types of coils. This is the first folding level of protein conformation.
Contractile tissue that produces movement in animals.
A group of peptide antibiotics from BACILLUS brevis. Gramicidin C or S is a cyclic, ten-amino acid polypeptide and gramicidins A, B, D are linear. Gramicidin is one of the two principal components of TYROTHRICIN.
The naturally occurring or experimentally induced replacement of one or more AMINO ACIDS in a protein with another. If a functionally equivalent amino acid is substituted, the protein may retain wild-type activity. Substitution may also diminish, enhance, or eliminate protein function. Experimentally induced substitution is often used to study enzyme activities and binding site properties.
An adenine nucleotide containing one phosphate group which is esterified to both the 3'- and 5'-positions of the sugar moiety. It is a second messenger and a key intracellular regulator, functioning as a mediator of activity for a number of hormones, including epinephrine, glucagon, and ACTH.
Striated muscle cells found in the heart. They are derived from cardiac myoblasts (MYOBLASTS, CARDIAC).
A pyrazine compound inhibiting SODIUM reabsorption through SODIUM CHANNELS in renal EPITHELIAL CELLS. This inhibition creates a negative potential in the luminal membranes of principal cells, located in the distal convoluted tubule and collecting duct. Negative potential reduces secretion of potassium and hydrogen ions. Amiloride is used in conjunction with DIURETICS to spare POTASSIUM loss. (From Gilman et al., Goodman and Gilman's The Pharmacological Basis of Therapeutics, 9th ed, p705)
A salt used to replenish calcium levels, as an acid-producing diuretic, and as an antidote for magnesium poisoning.
A calcium channel blocker that is a class IV anti-arrhythmia agent.
CO activates the large conductance calcium-activated potassium channel, BK. Falls in CO that occur as a consequence of hypoxia ... it leads to downstream potassium channel closure of both O2-sentive TASK-like and BK channels An increased PCO2 is detected ... The carotid body is a small cluster of chemoreceptor cells, and supporting sustentacular cells. The carotid body is located in ... The role of reactive oxygen species in hypoxia sensing is also under question. The oxygen dependent enzyme haem-oxidase has ...
... such as small-conductance Ca2+-activated potassium (SK) channels. Calmodulin mediates many crucial processes such as ... "The neuronal voltage-dependent sodium channel type II IQ motif lowers the calcium affinity of the C-domain of calmodulin". ... take calcium out of the cytoplasm or store it in the endoplasmic reticulum and this control helps regulate many downstream ... Arabidopsis thaliana contains about 50 different CML genes which leads to the question of what purpose these diverse ranges of ...
... that are activated by changes in membrane potential ligand-gated ion channel Ion channels mediated by the binding of small ... Calcium (Ca2+) channel blockers Chloride (Cl−) channel blockers Potassium (K+) channel blockers Sodium (Na+) channel blockers ... X-ray crystallography provides a structural image of the channel and molecule in question. Determining the hydrophobicity of ... Linsdell P (February 2014). "Cystic fibrosis transmembrane conductance regulator chloride channel blockers: Pharmacological, ...
CO activates the large conductance calcium-activated potassium channel, BK. Falls in CO that occur as a consequence of hypoxia ... it leads to downstream potassium channel closure of both O2-sentive TASK-like and BK channels An increased PCO2 is detected ... The carotid body is a small cluster of chemoreceptor cells, and supporting sustentacular cells. The carotid body is located in ... The role of reactive oxygen species in hypoxia sensing is also under question. The oxygen dependent enzyme haem-oxidase has ...
In neurons, small-conductance calcium-activated potassium (KCNN/SK/KCa2) channels maintain calcium homeostasis after N-methyl-D ... Since calcium plays a central role in microglial activation, we further addressed whether KCNN/SK/KCa2 channel activation ... In this study, we addressed the question whether KCNN/SK/KCa2 channels activation affected inflammatory responses of primary ... Furthermore, CyPPA reduced downstream events including tumor necrosis factor alpha and interleukin 6 cytokine production and ...
Voltage-gated potassium channels related to the Shal gene of Drosophila (Kv4 channels) mediate a subthreshold-activating ... Neither IBa(Ca) nor levels of the voltage-gated calcium channel coded by Dmca1A (cacophony, Calcium channel α1 subunit, type A ... One question is whether, given enough time, the mechanisms of synaptic homeostasis can adjust to the change in ion channel ... Shal currents are activated by small EPSPs and modulate post-synaptic potentials, backpropagation of action potentials, and ...
Spatial separation of endothelial small- and intermediate-conductance calcium-activated potassium channels (KCa) and connexins ... The low density of TRPV4 channels and IK channels in the EC membrane (table S1) raises fundamental questions about how these ... The current densities of TRPV4 channels, as well as those of IK and SK channels (the downstream targets of TRPV4 in the EDH ... Gating of recombinant small-conductance Ca-activated K+ channels by calcium. J. Gen. Physiol. 111, 565-581 (1998).. ...
... such as small-conductance Ca2+-activated potassium (SK) channels. Calmodulin mediates many crucial processes such as ... "The neuronal voltage-dependent sodium channel type II IQ motif lowers the calcium affinity of the C-domain of calmodulin". ... take calcium out of the cytoplasm or store it in the endoplasmic reticulum and this control helps regulate many downstream ... Arabidopsis thaliana contains about 50 different CML genes which leads to the question of what purpose these diverse ranges of ...
... one small conductance calcium-regulated channel gene; one KCNQ channel gene; and four cyclic nucleotide-gated channel genes. In ... a large conductance calcium-activated channel gene (slowpoke); a slack subunit relative; three members of theeag family (eag, ... elegans protein than to known vertebrate calcium channels. Additional fly calcium channel subunits include one β, one γ 2, and ... The fly potassium channel family includes five Shaker-like genes (Shaker, Shab, Shal, and twoShaws); ...
... calcium channels lead to a transient increase in calcium concentration that in turn activate a plethora of cellular functions, ... Twenty-five years after the first purification of a high-voltage calcium channel, the concept of a flexible stoichiometry to ... More strikingly, most of the α1-subunit interacting proteins, such as the β-subunit and small GTPases, regulate both gating and ... form supramolecular assemblies containing effectors and regulatory proteins that couple calcium influx to the downstream signal ...
... channels such as TRPM4 and TRPV4, as well as the calcium-activated chloride channel ANO1. Ependymal motile cilia appear at ... The ciliary PKD2-dependent conductance prefers potassium over calcium and sodium ions, with relative permeabilities PK/PCa/PNa ... produces a small ohmic current, but it is worrisome that they were not clearly distinct from endogenous channels found in host ... channel modulation by ATP and ADP was shown to be indirect, possibly downstream of the activation of an unidentified GPCR. ...
... is further demonstrated by studies showing that both hormones inhibit large conductance calcium-activated potassium channels in ... 68) suggested that following binding of an insulin-like ligand to DAF-2, AGE-1 is activated, and signaling downstream of this ... Batterham RL, Cowley MA, Small CJ, Herzog H, Cohen MA, Dakin CL, Wren AM, Brynes AE, Low MJ, Ghatei MA, Cone RD, Bloom SR: Gut ... KATP channel closure in turn raises intracellular concentrations of K+, leading to membrane depolarization and increased firing ...
4.1.3. Large Conductance Calcium-Activated (BK) Potassium Channels in SAH. Whether BK channels are impacted by SAH and ... Very little is known about changes in ion channel expression and function in cerebral vessels following transient global ... This paper focuses on ion channels and thus on processes at the cell surface, but one must not overlook the downstream effects ... raising many new questions. Several authors emphasize a loss of functional voltage-gated K+ channel (. ) in response to SAH, as ...
... are activated downstream of G-protein-coupled receptors (GPCRs). This latter class includes TRPC2, an ion channel expressed in ... TRPML3 channels have a preference for calcium over sodium and potassium and are blocked by gadolinium and verapamil but not by ... this question has been addressed by studying the responses of TRPM5 channels, in both cells expressing heterologous TRPM5 and ... The A419P mutation does not affect either the conductance or permeability of the TRPML3 channel. Instead, this gain-of-function ...
... potassium large conductance calcium-activated channel, subfamily M, alpha member 1; rs6480859, , HR = 1.06); in RBFOX1 (RNA ... a family of large conductance, voltage and calcium-sensitive potassium channels involved in the control of smooth muscle and ... One association is in the gene PRSS56, which has previously been linked to abnormally small eyes; one is in a gene that forms ... The first is rs4291789 (, HR = 1.07), which lies 34 kb downstream of ZIC2 (Zic family member 2). ZIC2 regulates two independent ...
... or small-conductance K+ channels (BKCa, IK, and SK3, respectively). The results of co-immunoprecipitation assays showed an ... To determine the mechanism underlying this TRPV4-induced relaxation of ASM, we blocked specific downstream molecules. We found ... Transient receptor potential vanilloid 4 (TRPV4) is a highly Ca2+-permeable non-selective cation channel that mediates Ca2+ ... relaxation was abolished by the NCX inhibitors KB-R7943 and LiCl but not by specific inhibitors of the Ca2+-activated large-, ...
calcium wave. gap junction mimetic peptides were originally designed to mimic the docking gate of gap junction channels (11, 13 ... Long treatment with this peptide resulted in conductances that were not significantly smaller than observed in untreated cells ... required for significant effects on channel currents as shown here or on downstream events such as ATP release or calcium wave ... 60 mV were applied to activate pannexin channels. 32Gap24 attenuated the currents in a dose-dependent manner. Carbenoxolone ...
Large-Conductance Calcium- and Voltage-Activated Potassium Channels (BK). BK channels are large-conductance calcium- and ... Little, HJ; Dolin, SJ; Halsey, MJ. Calcium channel antagonists decrease the ethanol withdrawal syndrome. Life Sci 1986, 39, ... Many intriguing questions remain to be answered, such as how ethanol affects the splicing machinery. The oxidative stress ... The D2S and D2L isoforms also differ in their effects on downstream protein phosphorylation. D2S has been suggested to decrease ...
Stretch-activated two-pore-domain (K2P) potassium channels in the heart: Focus on atrial fibrillation and heart failure. Prog ... Calcium cycling proteins and heart failure: mechanisms and therapeutics. J Clin Invest. 2013;123(1):46-52.. View this article ... Subsequently, parallel conductance (Vp) was determined by 10 μl injection of 15% saline into the right jugular vein to ... Global TREK-1 KO alters JNK phosphorylation. (A) Immunoblotting results for phosphorylated JNK (phospho-JNK) and the downstream ...
... elegans reproductive behavior shows how T-type calcium channels engage and disengage target neurons from these critical ... cca-1 encodes the pore-forming subunit of a low-voltage activated (LVA) T-type calcium channel and is the only T-type calcium ... The peak conductance was shifted by −10 mV, with wild-type channels exhibiting peak conductance at −20 mV and mutant channels ... Because T-type channels are low-voltage-activated, they need only a small depolarization to open, and the current they pass can ...
2014). Molecular mechanisms contributing to TARP regulation of channel conductance and polyamine block of calcium-permeable ... 2020). The pore domain in glutamate-gated ion channels: Structure, drug binding and similarity with potassium channels. Biochim ... usually small, induce closure of the binding pocket, leading to opening of the channel pore, whereas antagonists, usually large ... and subtle changes in LBD interactions can be readily translated to the downstream extracellular vestibule of channel pore to ...
Open Questions. Experimental. At the time of writing, relatively little is known about the molecular signaling mechanisms that ... Each conductance in the Liu model is regulated by three \(Ca^{2+}\)-dependent "sensors" which activate and inactivate on ... the activity sensors and their downstream targets is unknown and the means by which trafficking or modification of ion channel ... is the intracellular calcium concentration, \(G_i\) is the maximum value of the maximal conductance for the \(i^{th}\) current ...
Large conductance calcium- and voltage-activated potassium channels (BK channels) activate in response to calcium influx during ... This ability of optogentically activated subpopulations of neurons to drive appropriate downstream maps suggests that ... BK channel blockers also enhanced the appearance of delayed responses, particularly following the second action potential in ... Here, we address this question by imaging the spread and synchronization of cortical activity using voltage-sensitive dyes ( ...
Consequently, downstream targets of p300/CBP, such as p53 (Refs 10,11,12,13,14,15), are activated and cause cell death. A ... The primary calcium release channel on endoplasmic reticulum membranes is the inositol 1,4,5-trisphosphate receptor (IP3R). ... Hydrogen Sulfide As Endothelium-derived Hyperpolarizing Factor Sulfhydrates Potassium Channels Circulation Research. Nov, 2011 ... Feb, 2015 , Pubmed ID: 25660019 Rheb, a ubiquitous small GTPase, is well known to bind and activate mTOR, which augments ...
Increased firing is associated with reduced small-conductance calcium-activated potassium channel (SK) currents and decreased ... allowing downstream expression of other transgene products such as fluorophores and calcium indicators. The morphology of ... How the nucleus accumbens integrates information from multiple upstream regions has been a central question for decades. In ... neural signaling can be bi-directionally controlled through expression of light-sensitive ion channels (opsins) in mammalian ...
2003) Blockade of the intermediate-conductance calcium-activated potassium channel as a new therapeutic strategy for restenosis ... large-conductance KCa) by ≈1,000× and KCa2.3 (small-conductance KCa) by ≈100×. However, in electrophysiological patch-clamp ... To address this question we conducted a series of experiments applying the mouse model of UUO to induce experimental renal ... TGFβ1 potently promotes proliferation of renal fibroblasts via a downstream mechanism that is largely mediated by bFGF (7, 12). ...
By contrast, the calcium-dependent potassium channel Slowpoke (BK) is not essential for postnatal speeding, though it also ... Ca(2+)-activated K(+) channels reduce network excitability, improving adaptability and energetics for transmitting and ... Little is known about the normal function of ANK1 in the healthy brain, nor the role it may play in AD. This study has ... To address this question, this study overexpressed a Rhodopsin-1 mutant prone to aggregate either in vestigial- or engrailed- ...
Nomenclature and Molecular Relationships of Calcium-Activated Potassium Channels *. International Union of Pharmacology. LIII. ... monovalent-selective cation channels with ∼25 pS single-channel conductances (Launay et al., 2002; Hofmann et al., 2003; Nilius ... TRPA1 is also activated downstream of G protein-coupled receptors that stimulate PLC and may depolarize nociceptors in response ... For TRPV1, M4, M5, and M8, the TRP channels that are most sensitive to voltage changes, an important question is which residues ...
Calcium and potassium currents in ventricular myocytes isolated from diabetic rats. J Physiol 1993;470:411-429pmid:8308734. ... or large animal models need to be performed to answer this question and to determine the feasibility of using a sodium channel ... Whereas IKr and IKs play little or no role in regulating the APD in adult mouse myocytes (9,10), INaP has a major role, such ... The diabetic myocytes also showed an increase in INaP that was reversed by activated PI3K or PIP3. The increases in APD and I ...
slo-1 encodes the BK potassium channel. Electrophysiological analysis shows that ethanol activates the channel in vivo, which ... we find that SLO-1 is localized near L-type calcium channels in muscle, thereby providing a mechanism coupling calcium influx ... Our analyses suggest that decreased GCY-12 levels in the cilia of chb-3 mutants may cause the suppression of the small-body ... Here we show that the C. elegans DAPC is essential for proper localization of SLO-1, the large conductance, voltage-, and ...
However, its calcium (Ca2\(^{2+}\)) permeability and single channel conductance are low and for some applications longer- ... Synthetic light-activated ion channels for optogenetic activation and inhibition (2018) Beck, Sebastian ; Yu-Strzelczyk, Jing ... Moreover, there is need for an efficient light-gated potassium (K\(^{+}\)) channel that can rapidly inhibit spiking in targeted ... Ribosomal S6 kinase 2 (RSK2) acts as a regulator and downstream effector of ERK. In the brain, RSK2 is predominantly expressed ...
The charge carrier was 2 mM Ba2+ to facilitate block of inward rectifier K channels and minimize Ca2+ activated conductances. ... Voltage-sensing arginines in a potassium channel permeate and occlude cation-selective pores. Neuron. 2005;45(3):379-388.. View ... To address this question, we developed a mouse model for HypoPP with a targeted CaV1.1 R528H mutation. The Cav1.1 R528H mice ... On average, the amplitude of the Ca2+ transient under voltage clamp conditions was 3-fold smaller in R528Hm/m fibers compared ...
... conductance potassium channel beta-subunit can interact with and modulate the functional properties of a calcium-activated ... rule out that small changes in β1-subunit expression could facilitate the opening of the pore and either mask or mimic channel ... The need for our work is beyond question. Find Out More about the American Heart Association ... 14 This is also in keeping with genetic data showing the major downstream target for NO is the α-subunit.3,4 However, one ...
  • In neurons, small-conductance calcium-activated potassium (KCNN/SK/K Ca 2) channels maintain calcium homeostasis after N-methyl-D-aspartate (NMDA) receptor activation, thereby preventing excitotoxic neuronal death. (elsevier.com)
  • L3 calcium response kinetics postsynaptic to photoreceptors resemble the sustained calcium signals of photoreceptors, whereas L2 neurons decay transiently. (sdbonline.org)
  • Functional implications as well as similarities and differences to Kv1-4 channel localization in mammalian neurons are discussed. (sdbonline.org)
  • In the vertebrate central nervous system, the neuromodulator serotonin is released by a small population of neurons that project widely and exert influence on neural circuits throughout the brain. (elifesciences.org)
  • AMPA and NMDA receptors depolarize postsynaptic neurons when activated by L-glutamate. (tcdb.org)
  • This article focuses on homeostatic plasticity of single neurons, in particular, the activity-dependent regulation of ion channel densities that determine the intrinsic properties of neurons. (scholarpedia.org)
  • Methods for one-photon fluorescent imaging of calcium dynamics can capture the activity of hundreds of neurons across large fields of view at a low equipment complexity and cost. (salk.edu)
  • This study monitored and analyzed for the first time the activity patterns of a small cluster of third-order neurons (so-called ventrolateral protocerebrum neurons) to asymmetric olfactory stimulation using two-photon calcium imaging. (sdbonline.org)
  • Studies in the lab are carried out using a full range of electrophysiological techniques including extracellular field potential recording, intracellular recording,whole cell and single channel recording in hippocampal slices and cultured neurons. (stanford.edu)
  • The courtship song vibrates the arista (a feathery extension of the Drosophila antenna that serves as the sound receiver)-this causes rotation of the antenna and thereby opens mechanosensitive channels housed within antennal neurons, so-called Johnston's organ (JO) neurons (JONs) 11 , 12 (Fig. 1a , top). (nature.com)
  • First, voltage-insensitive ("leak") ion channels, which act to hyperpolarize neurons, have repeatedly appeared in genetic screens for targets of volatile anesthetics, 2 , 3 , 5 , 7 suggesting that they act, at least in part, through changes in voltage and resistance across the plasma membrane. (asahq.org)
  • CGNs (cerebellar granule neurons) are small glutamatergic cells that constitute the largest homogeneous neuronal population in the mammalian brain. (biochemj.org)
  • First, the levels of calcium ions in the neurons, which play a key role in neurons' activity, were imaged using a calcium-sensitive biosensor. (elifesciences.org)
  • The experiments showed that class IV neurons responded to heat by producing a characteristic burst of electrical activity followed by a pause, and that this pattern of electrical activity was accompanied by a large rise in the calcium signal. (elifesciences.org)
  • Uncovering the intrinsic cellular properties that control the input-output processing within brain microcircuits is highly challenging due to the large diversity of voltage-gated ion channels (VGCs) expressed by individual neurons and their variable distribution across the cell structure. (eneuro.org)
  • Zinc increased tonic activity in the depolarized state when neurons were intracellularly dialyzed with EGTA but attenuated the neuronal activity when BAPTA was used as an intracellular calcium buffer. (bvsalud.org)
  • Falls in CO that occur as a consequence of hypoxia would lead to closure of this potassium channel and this would lead to membrane depolarisation and consequence activation of the carotid body. (wikipedia.org)
  • Shaker, Shaw, and Shal but not Shab channels localize to the non-myelinated GF axonal membrane and axon terminals. (sdbonline.org)
  • Likewise, regulation of the number of channels in the plasma membrane is performed by altering the release of the α 1 -subunit from the endoplasmic reticulum, by reducing its degradation or enhancing its recycling back to the cell surface. (frontiersin.org)
  • Electrical excitability and synaptic transmission rely on an extended repertoire of voltage-activated ion channels that respond to membrane depolarization by opening an ion-selective pathway across the membrane. (frontiersin.org)
  • Sodium- and potassium-selective channels are mostly involved in the propagation and shaping of electrical signals while calcium channels that are activated during an action potential are responsible for translating changes in the voltage across the membrane into a local calcium increase. (frontiersin.org)
  • In this review, we focus on the composition of putative ion channels found in both types of cilia and in the periciliary membrane and discuss their proposed functions. (rupress.org)
  • Healthy cerebrovascular myocytes express members of several different ion channel families which regulate resting membrane potential, vascular diameter, and vascular tone and are involved in cerebral autoregulation. (hindawi.com)
  • Membrane potential of cerebrovascular smooth muscle cells and thus dilation and constriction of cerebral arteries are directly dependent on potassium conductance [ 5 , 6 ]. (hindawi.com)
  • They have a modular architecture with four domains: the intracellular C-terminal domain (CTD) that is involved in synaptic targeting, the transmembrane domain (TMD) that forms the ion channel, the membrane-proximal ligand-binding domain (LBD) that binds agonists such as L-glutamate, and the distal N-terminal domain (NTD). (tcdb.org)
  • We found that at CA3-CA3 connections in hippocampal slice cultures, a fast-activating, slowly inactivating K+ conductance similar to the so-called delay current (ID) is responsible for the delayed appearance of the first spike upon membrane depolarisation, for action potential repolarisation and for modulation of transmitter release. (jove.com)
  • These theoretical ideas were soon corroborated by experiments in vertebrate and invertebrate preparations that described activity-dependent changes in membrane conductances occurring over a slow timescale (hours to days) that tended to stabilize a particular activity regime such as rhythmic bursting. (scholarpedia.org)
  • Another prediction is that the activation/deactivation kinetics of BK Ca would be slowed if β1-subunit levels had a functional impact on the number of channels expressing both subunits at the membrane. (ahajournals.org)
  • Activation of the channel can occur only if there is simultaneous glutamate and glycine binding and partial depolarisation of the membrane potential. (rcpsych.org)
  • However, functional assessment of HypoPP mutant channels has been hampered by difficulties in achieving sufficient plasma membrane expression in cells that are not of muscle origin. (rupress.org)
  • The activation of KCa3.1 hyperpolarized membrane potential and, by promoting the driving force for calcium, induced calcium entry through TRPV4, a cation channel of the transient receptor potential family. (biomedcentral.com)
  • Normal human B and T cells, Reh cells (from human B cell leukemia), and Jurkat cells (from human T cell leukemia) were studied by flow cytometry to detect morphological changes (scatter) and viability (propidium iodide uptake), and by patch clamp recordings to monitor membrane conductance. (chemweb.com)
  • One of them is TASK1 channel, which stabilizes resting membrane potential especially during cardiac ischemia/hypoxia because disruption of ion homestasis eventually causes cell death.Activation of protein kinase C (PKC) via adenosine receptors is known to be involved in the cardioprotection of ischemic preconditioning. (oatd.org)
  • Synaptic transmission at fast synapses occurs in less than 1/1000 of a second and is attributable to the ability of the fast-acting neurotransmitters to open ligand-operated ion channels present in the plasma membrane of the postsynaptic cells. (sciencemag.org)
  • The apparent lack of desensitization of the response is consistent with two processes: a rapid-onset phosphorylation of KCNE1 channel subunit and a slower-onset of regulation by depletion of plasma membrane PIP 2 . (biomedcentral.com)
  • Furthermore, repeated exposure to cocaine can alter the mechanisms underlying transmitter release in response to a depolarizing agent and decreases the efficiency of sodium and calcium channels in the plasma membrane. (drugabuse.gov)
  • A less understood Gβγ-mediated mechanism downstream of Ca 2+ entry is the binding of Gβγ to SNARE complexes, which facilitate the fusion of vesicles with the cell plasma membrane in exocytosis. (sciencemag.org)
  • The regulated internalization has been characterized as a principal mechanism for removing cell-surface receptors from the plasma membrane, and signaling to downstream targets of receptors. (springer.com)
  • We combined whole-cell patch-clamp recordings and two-photon dendritic calcium imaging to examine IS3 cell membrane and dendritic properties. (eneuro.org)
  • In darkness, there is a steady inward current (the "dark current") through a cation conductance on the outer-segment membrane (Hagins et al. (utah.edu)
  • 1) Background: In this work, we focus on the activity of large-conductance voltage- and Ca2+-activated potassium channels (BK) from the inner mitochondrial membrane (mitoBK). (bvsalud.org)
  • Nevertheless, depending on the isoformal composition of mitoBK channels in a given membrane patch and the type of auxiliary regulatory subunits (which can be co-assembled to the mitoBK channel protein) the characteristics of conformational dynamics of the channel protein can be altered. (bvsalud.org)
  • Here, we would like to examine the existence of dynamic diversity of BK channels from the inner mitochondrial and cellular membrane from human glioblastoma (U-87 MG). Not only the standard characteristics of the spontaneous switching between the functional states of the channel is discussed, but we put a special emphasis on the presence and strength of correlations within the signal describing the single-channel activity. (bvsalud.org)
  • Kinetic properties of membrane transporters are typically poorly defined because high-resolution functional assays analogous to single-channel recordings are lacking. (sciencemag.org)
  • The ability of cells to maintain a large gradient of calcium across their outer membrane is universal. (heavenforum.org)
  • Damage the ability of the plasma membrane to maintain this gradient and calcium will flood into the cell, precipitating calcium phosphate, damaging the ATP-generating machinery, and kill the cell. (heavenforum.org)
  • The evidence we have from molecular biology, together with the toxic nature of prolonged high Ca2+ levels inside cells, argues strongly that primeval cells must have had Ca2+ pumps to keep their free intracellular Ca2+ low, setting the scene for the ' calcium pressure' across then plasma membrane to be exploited to act as the source for cell activation. (heavenforum.org)
  • Mild haemolysis is not converted to plasmin which degrades fibrin into fibrin degradation products fdp levels reflect the downstream tubule network express connexins membrane proteins and intermediatelaments play a role for focal adhesion kinase bioessays a truong. (junoon.com)
  • Stomatal opening is driven by H+ extrusion through plasma membrane H+ ATPases that are activated by auxins (Lohse and Hedrich, 1992), red light ( Serrano, 1998 ), and blue light (Assmann et al. (ucsd.edu)
  • 1986), causing plasma membrane hyperpolarization proposed to drive K+ uptake into guard cells via inward-rectifying K+ (K+in) channels (Schroeder et al. (ucsd.edu)
  • The way it emerges is through a feedback from the cellular level where the membrane potential is formed, a macroscopic phenomenon, to the molecular level of ionic channels, which produce local transmembrane currents. (romainbrette.fr)
  • In a sequence of select publications, Orrenius and associates showed that the toxicity of paracetamol and sundry electrophilic quinones byzantine invoice to calcium pumps' in the plasma membrane or endo- plasmic reticulum. (autoportal.ru)
  • We tested several connexin and pannexin mimetic peptides and observed attenuation of channel currents that is not compatible with sequence specific actions of the peptides. (physiology.org)
  • Connexin mimetic peptides inhibited pannexin channel currents but not the currents of the channel formed by connexins from which the sequence was derived. (physiology.org)
  • Pannexin mimetic peptides did inhibit pannexin channel currents but also the channels formed by connexin 46. (physiology.org)
  • Detecting gating pore currents is more challenging in Na V and Ca V channels because each mutant channel has only a single gating pore conductance, unlike the fourfold R/X mutation for homotetrameric Shaker K + channels. (rupress.org)
  • Further, without A-type potassium currents in the dendrites, spike generation is facilitated at more distal synaptic input locations. (eneuro.org)
  • Our models predicted the presence of fast delayed rectifier potassium currents and the absence of slow delayed rectifier channels, and this was confirmed experimentally. (eneuro.org)
  • These techniques were applied to the experimental series of single channel currents. (bvsalud.org)
  • According to the original biochemical characterization of skeletal muscle Dihydropyridine receptors, HVA calcium channels are multi-subunit protein complexes consisting of a pore-forming subunit (α 1 ) associated with four additional polypeptide chains β, α 2 , δ, and γ, often referred to as accessory subunits. (frontiersin.org)
  • In situ hybridization revealed the presence of different BK channel splice variants (X1 +24 , X2 +92 , SS2 +174 and SS4 +81 ) in combination with β 1, β 2, and β 4 subunits in rat cerebral arteries [ 13 ]. (hindawi.com)
  • Genes for the TRP ion channel subunits were first defined in the Drosophila visual system. (aspetjournals.org)
  • A heterologous expression system was developed to examine molecular aspects of the α and β subunits of the CNG channel. (ubc.ca)
  • As seen for the subunits of the native CNG channel the heterologously expressed α and β subunits coimmunoprecipitated. (ubc.ca)
  • Reconstitution of the heterologously expressed channel complex comprising the 80 kDa α and complete β subunits generated functional channels. (ubc.ca)
  • Release of Gβγ subunits from activated G proteins decreases the activity of voltage-gated Ca 2+ channels (VGCCs), decreasing excitability. (sciencemag.org)
  • Nevertheless, depending on the cell type, composition of membranes can vary, and mitoBK channels can be expressed in different splice variants as well as they can be co-assembled with different types of auxiliary ß subunits. (bvsalud.org)
  • They interact with receptors, G protein α subunits and downstream targets to coordinate multiple, different GPCR functions. (pubmedcentralcanada.ca)
  • Whatever the mode of G protein activation, the Gα and Gβγ subunits both interact with effector molecules, such as phospholipases and ion channels, in a manner that leads to their activation. (pubmedcentralcanada.ca)
  • Since calcium plays a central role in microglial activation, we further addressed whether KCNN/SK/K Ca 2 channel activation affected the changes of intracellular calcium levels, [Ca 2+ ] i, , in microglial cells. (elsevier.com)
  • Control of the intracellular calcium concentration ([Ca 2+ ] i ) is critical to the regulation of airway smooth muscle (ASM) function and mediates many processes, including contraction, proliferation, and gene expression ( Hirota and Janssen, 2007 ). (frontiersin.org)
  • During pathological brain insults such as cerebral ischemia, a rapid increase of intracellular calcium initiates apoptotic and necrotic cell death and reactive gliosis. (biomedcentral.com)
  • We showed that stimulation of muscarinic acetylcholine receptors on endothelial cells of mouse arteries exclusively activated TRPV4 channels that were localized at myoendothelial projections (MEPs), specialized regions of endothelial cells that contact smooth muscle cells. (sciencemag.org)
  • Ionotropic receptors allow the passage of charged ions into the neuron, for example chloride (Cl - ) and calcium (Ca 2+ ). (rcpsych.org)
  • Glutamatergic receptors are grouped according to similarities in amino acid sequence and pharmacodynamic properties such as affinity for glutamate and threshold for channel opening. (rcpsych.org)
  • Ionotropic glutamatergic receptors open cation-permeable channels to mediate sodium (Na + ), potassium (K + ) or calcium (Ca 2+ ) ion flow. (rcpsych.org)
  • The AMPA and the kainate receptors are collectively termed 'non-NMDA' receptors and appear to control conductance of Na + and K + through channels that exhibit rapid kinetics. (rcpsych.org)
  • The zinc-induced augmentation of firing activity was mediated via the inhibition of small-conductance calcium-activated potassium (SK) channels with not only the contribution of voltage-gated L-type calcium channels (VGCCs) and ryanodine receptors (RyRs), but also through the activation of VGCCs via melastatin-like transient receptor potential channels. (bvsalud.org)
  • In contrast, gonadotrophs fire single, high-amplitude spikes with limited ability to promote calcium influx and exocytosis, whereas activated G q/11 -coupled receptors in these cells transform single-action potential spiking into the plateau-bursting type of electrical activity and trigger periodic high-amplitude calcium signals and exocytosis of prestored secretory vesicles. (conicyt.cl)
  • The Drosophila visual system , for instance, splits information into channels with different temporal properties directly downstream of photoreceptors in the first-order interneurons of the OFF pathway, L2 and L3. (sdbonline.org)
  • This study utilizes protein trap fly strains with endogenously tagged channels to analyze the spatial expression patterns of the four Shaker-related voltage-gated potassium channels, Kv1-4, in the larval, pupal, and adult Drosophila ventral nerve cord. (sdbonline.org)
  • This study constitutes a first step toward systematically analyzing sub-neuronal potassium channel localization in Drosophila. (sdbonline.org)
  • dSlo(-)) is shaped in the female fruit fly (Drosophila melanogaster) R1-R6 photoreceptor-LMC circuits (R-LMC-R system) through synaptic feedforward-feedback interactions and reduced R1-R6 Shaker and Shab K(+) conductances. (sdbonline.org)
  • Despite the very small spatial separation between the two antennae and the redundancy in sensory neuron projection to both sides of the brain, Drosophila can resolve the concentration gradient by comparing the signal strength between the two antennae . (sdbonline.org)
  • The transient receptor potential (TRP 1 ) ion channels are named after the role of the channels in Drosophila phototransduction. (aspetjournals.org)
  • Three genes ( TRP, TRPL , and TRP γ) encode TRP channels that are involved in fly vision, but there are at least 13 TRP-like genes in Drosophila . (aspetjournals.org)
  • Our work identifies a Drosophila homolog of a deaf-blindness gene as a new component of the circadian output pathway and an important regulator of ion channel expression, and suggests novel roles for Usher proteins in the mammalian nervous system. (prolekare.cz)
  • In Drosophila , the ion channel narrow abdomen, an ortholog of the C. elegans NCA channels, drive the pigment dispersing factor (PDF) neuropeptide release, regulating circadian behavior. (genetics.org)
  • TRPV4 channels play a major role in endothelial-dependent vasodilation, a function mediated by local Ca 2+ influx through clusters of functionally coupled TRPV4 channels rather than by a global increase in endothelial cell Ca 2+ . (sciencemag.org)
  • Cooperative opening of clustered TRPV4 channels specifically amplified Ca 2+ influx at MEPs. (sciencemag.org)
  • To coordinate all these responses calcium channels form supramolecular assemblies containing effectors and regulatory proteins that couple calcium influx to the downstream signal cascades and to feedback elements. (frontiersin.org)
  • Twenty-five years after the first purification of a high-voltage calcium channel, the concept of a flexible stoichiometry to expand the repertoire of mechanisms that regulate calcium channel influx has emerged. (frontiersin.org)
  • Transient receptor potential vanilloid 4 (TRPV4) is a highly Ca 2+ -permeable non-selective cation channel that mediates Ca 2+ influx to increase [Ca 2+ ] i , which then directly or indirectly regulates the contraction and relaxation of ASM. (frontiersin.org)
  • It is the only ionotropic receptor to control Ca 2+ conductance in addition to the conductance of Na + and K + . When the channel is activated there is an influx of Na + and Ca 2+ ions and an efflux of K + ions. (rcpsych.org)
  • Binding of magnesium (Mg 2+ ) ions to sites within the channel prevents Ca 2+ influx. (rcpsych.org)
  • Over the past few years, a large number of studies suggested that astroglial calcium influx after ischemia could be mediated by the activation of Ca 2+ permeable cation channels such as transient receptor potential (TRP) channels. (biomedcentral.com)
  • Both these responses depended on two TRPA channels and the L-type voltage-gated calcium channel (L-VGCC), showing that the thermosensation provokes Ca 2+ influx. (elifesciences.org)
  • With its inward-rectifying current-voltage relationship and high calcium permeability, TRPC4 channels permit calcium influx once the channel is opened by muscarinic receptor stimulation. (bvsalud.org)
  • I then demonstrated that RGS2 is a negative regulator of glucose-stimulated insulin secretion (GSIS), because Rgs2-overexpressing MIN6 cells and mouse islets showed reduced GSIS, due to lower calcium influx and oxygen consumption, whereas Rgs2 knockout cells exhibited increased GSIS. (ubc.ca)
  • So far, little is known about the function of KCNN/SK/K Ca 2 channels in non-neuronal cells, such as microglial cells. (elsevier.com)
  • Neuronal excitability is determined by the combination of different ion channels and their sub-neuronal localization. (sdbonline.org)
  • Re-expression of Kv1-4 channels at pupal stage 6 starts with abundant channel localization in neuronal somata, followed by channel targeting to the respective sub-neuronal compartments until late pupal life. (sdbonline.org)
  • In response to these afferent inputs, neuronal pathways are activated that influence energy flux and nutrient metabolism in the body and ensure reproductive competency. (diabetesjournals.org)
  • Both activated gliosis and neuronal loss were attenuated in KCa3.1 −/− pMCAO mice. (biomedcentral.com)
  • We show that DYSC is expressed in major neuronal tracts and regulates expression of the calcium-activated potassium channel SLOWPOKE (SLO), an ion channel also required in the circadian output pathway. (prolekare.cz)
  • The N-methyl-D-aspartate receptor (NMDAR) is a principal subtype of glutamate-gated ion channel and plays key roles in neuronal plasticity and memory functions. (springer.com)
  • Depending on the intracellular buffering of calcium by chelation, zinc has the following two apparent effects on neuronal excitability: enhancement or reduction. (bvsalud.org)
  • This suggests that neuronal excitability can be modulated by zinc, depending on the internal calcium buffering capacity. (bvsalud.org)
  • In this study, we elucidated the mechanisms of zinc-mediated alterations in neuronal excitability and determined the effect of calcium-related channels on zinc-mediated alterations in excitability. (bvsalud.org)
  • We suggest that zinc modulates the dopaminergic neuronal activity by regulating not only SK channels as calcium sensors, but also VGCCs or RyRs as calcium sources. (bvsalud.org)
  • Our results suggest that the cytosolic calcium-buffering capacity can tightly regulate zinc-induced neuronal firing patterns and that local calcium-signaling domains can determine the physiological and pathological state of synaptic activity in the dopaminergic system. (bvsalud.org)
  • One example of such signaling involves a local increase in Ca2+ concentration near a class of Ca2+ channels (L-type) different from those that trigger presynaptic transmitter release, subsequently leading to activation of an exemplar transcription factor, CREB, a regulator of transcription of many important neuronal genes. (stanford.edu)
  • conformational changes induced by extracellular agonist binding deform and splay open the inner helix bundle crossing that occludes ion flux through the channel. (tcdb.org)
  • The GluN1/2A ligand binding domain (LBD) interface interactions play a key role in determining channel function, and subtle changes in LBD interactions can be readily translated to the downstream extracellular vestibule of channel pore to adopt a conformation that may affect memantine, Zn 2+ and Mg 2+ binding. (tcdb.org)
  • Local anesthetics (LAs) are known to bind Na + channels in the closed, open, and inactivated states and reach their binding sites via extracellular and intracellular access pathways. (aspetjournals.org)
  • All secretory anterior pituitary cells exhibit spontaneous and extracellular calcium-dependent electrical activity, but differ with respect to the patterns of firing and associated calcium signaling and hormone secretion. (conicyt.cl)
  • The developmental time course of tagged Kv1-4 channel expression corresponds with previously published data on developmental changes in single neuron physiology, thus indicating that protein trap fly strains are a useful tool to analyze developmental regulation of potassium channel expression. (sdbonline.org)
  • Mitochondrial large-conductance voltage- and Ca2+-activated potassium channels (mitoBK) exhibit substantial similarities in their physiology regardless of the channel's location. (bvsalud.org)
  • This chapter begins with general information on the role of 5'-AMP activated kinase (AMPK) in human physiology and the molecular mechanisms that control this kinase. (intechopen.com)
  • Despite enormous advances since then, there remain multiple emerging and unanswered questions about the fundamental details of the biochemical roles for Gβγ in GPCR-dependent G protein activation, as well as questions about broader roles in novel signaling mechanisms, physiology and pathophysiology. (pubmedcentralcanada.ca)
  • Because our mechanistic understanding of this process remains incomplete, studying the normal physiology of calcium-dependent β-cell function may uncover new avenues for the treatment or prevention of diabetes. (ubc.ca)
  • In this review, we discuss the structural basis, interplay and functional role of selected proteins that interact with the central pore-forming subunit of HVA calcium channels. (frontiersin.org)
  • Here, we summarize the structure-function relationship of a set of proteins that interact with and regulate the pore-forming subunit of high-voltage-activated (HVA) calcium channels. (frontiersin.org)
  • PEG accessibility is in the size range expected for the pore of innexin gap junction channels, consistent with a functional relatedness of innexin and pannexin channels. (physiology.org)
  • The pore domains in glutamate-gated ion channels have structures, drug binding properties and similarities with potassium channels ( Tikhonov and Zhorov 2020 ). (tcdb.org)
  • Mutations of Ca V 1.1, the pore-forming subunit of the L-type Ca 2+ channel in skeletal muscle, are an established cause of hypokalemic periodic paralysis (HypoPP). (rupress.org)
  • This convergence strongly supports the prevailing view that recurrent episodes of depolarization-induced weakness in HypoPP are caused by an aberrant inward current conducted by a gating pore leak in the voltage sensor domain of mutant Ca V 1.1 or Na V 1.4 channels ( Cannon, 2010 ). (rupress.org)
  • A gating pore current was described first in Shaker K + channels, where histidine-scanning mutagenesis studies to test for voltage-dependent shifts of proton accessibility to arginine residues in S4 surprisingly created a proton conduction pathway distinct from the K + -selective pore ( Starace and Bezanilla, 2001 ). (rupress.org)
  • This hypothesis on the coupled movement of Na + and LA in the closed channel explains seemingly contradictory data on how the outer-pore mutations as well as tetrodotoxin and μ-conotoxin binding affect the ingress and egress of LAs. (aspetjournals.org)
  • The selectivity filter separates the outer pore, which is targeted by tetrodotoxin (TTX), saxotoxin, and conotoxins, from the inner pore, which is targeted by local anesthetics (LAs) and other small cationic drugs ( Zhorov and Tikhonov, 2004 ). (aspetjournals.org)
  • A structural model of the outer pore in the slow-inactivated channel has been recently proposed ( Tikhonov and Zhorov, 2007 ). (aspetjournals.org)
  • Inside the Na + channel pore, LAs bind state-dependently. (aspetjournals.org)
  • Previously published results from our laboratory identified a mechano-gated two-pore domain potassium channel, TREK-1, as a main mechanosensor in the smooth muscle of the human urinary bladder. (biomedcentral.com)
  • Previous animal studies provided evidence that bladder stretch can activate mechanosensitive two-pore domain potassium (K 2P ) channels [ 29 , 46 , 49 ]. (biomedcentral.com)
  • Ribosomal S6 kinase 2 (RSK2) acts as a regulator and downstream effector of ERK. (uni-wuerzburg.de)
  • Our results raised the possibility that suppression of this signaling pathway might also play a role in QT interval prolongation associated with diabetes, where reduced production of or sensitivity to insulin results in decreased activation of PI3K and its downstream effector, Akt. (diabetesjournals.org)
  • Only inhibitory peptides targeting KCNN3/SK3/K Ca 2.3 channels, but not KCNN2/SK2/K Ca 2.2 channel inhibition, reversed the CyPPA-effects on LPS-induced microglial proliferation. (elsevier.com)
  • The channel inhibition by peptides shares commonalities with channel effects of polyethylene glycol (PEG), suggesting a steric block as a mechanism. (physiology.org)
  • The inhibition of potassium channels by peptides from animal venoms is a subject of broad interest for its physiological and therapeutic applications [ 1 ]. (mdpi.com)
  • Several TRPC subfamily member proteins-especially TRPC1 and TRPC6-are upregulated in pathological VSMCs, and pharmacological inhibition of TRPC channel activity has been reported to improve hypertensive vascular remodeling in rodents. (bvsalud.org)
  • This study shows that the voltage-gated Ka channels Shaker and Shal contribute to the response properties of the major OFF pathway input L2. (sdbonline.org)
  • Once bound to Ca2+, calmodulin acts as part of a calcium signal transduction pathway by modifying its interactions with various target proteins such as kinases or phosphatases. (wikipedia.org)
  • These findings demonstrate that TRPA1 is the main molecular site through which a variety of environmental irritants and endogenous inflammatory mediators activate the pain pathway. (jneurosci.org)
  • Previous analyses suggest that lack of normal cilia causes the small-body phenotype through the activation of a signaling pathway which consists of the EGL-4 cGMP-dependent protein kinase and the GCY-12 receptor-type guanylyl cyclase. (stanford.edu)
  • Additionally, we examined the nitric oxide -induced effects on trabecular meshwork cell volume, the signal transduction pathway(s) and ion channel involved. (ufl.edu)
  • The results of the present study reveal a novel regulation of Kv2.1 by GDF15 mediated through the TGFβRII-activated Akt/mTOR pathway, which is a previously uncharacterized Smad-independent mechanism of GDF15 signalling. (biochemj.org)
  • However, in C. elegans , we found that loss of the PDF receptor PDFR-1 did not suppress gain-of-function sleep defects, suggesting an alternative downstream pathway. (genetics.org)
  • C-terminus of the surface mouse factor activates DT complex A, which is ADP library of the Energy-Transducing ligase surfactant 2( EEF2) in a coupling pathway, technologically flipping Transbilayer endosome. (evakoch.com)
  • Limitations of in vitro experiments on isolated human bladders included the inability to assess the full spectrum of TREK-1 related effects on voiding function as the channel is also expressed in the nervous system and therefore, may indirectly participate in micturition modulation via a neural pathway. (biomedcentral.com)
  • Cooperativity of TRPV4 channels at non-MEP sites was much lower, and cooperativity at MEPs was greatly reduced by chelation of intracellular Ca 2+ or AKAP150 knockout, suggesting that Ca 2+ entering through adjacent channels underlies the AKAP150-dependent potentiation of TRPV4 activity. (sciencemag.org)
  • In a mouse model of angiotensin II-induced hypertension, MEP localization of AKAP150 was disrupted, muscarinic receptor stimulation did not activate TRPV4 channels, cooperativity among TRPV4 channels at MEPs was weaker, and vasodilation in response to muscarinic receptor stimulation was reduced. (sciencemag.org)
  • Thus, endothelial-dependent dilation of resistance arteries is enabled by MEP-localized AKAP150, which ensures the proximity of PKC to TRPV4 channels and the coupled channel gating necessary for efficient communication from endothelial to smooth muscle cells in arteries. (sciencemag.org)
  • PKD2, PKD2-L1), but investigators have reported other channels in or near cilia, including other transient receptor potential (TRP) channels such as TRPM4 and TRPV4, as well as the calcium-activated chloride channel ANO1. (rupress.org)
  • To determine the mechanism underlying this TRPV4-induced relaxation of ASM, we blocked specific downstream molecules. (frontiersin.org)
  • The transient receptor potential vanilloid 4 (TRPV4) channel is a subclass of the TRPV ion channel family ( Ferreira and Faria, 2016 ). (frontiersin.org)
  • Double-labeled staining showed that KCa3.1 and TRPV4 channels co-localized in astrocytes. (biomedcentral.com)
  • TRPV1, TRPV4, and TRPA1 cation channels are members of the vanilloid (TRPV) and ankyrin (TRPA) subfamily of transient receptor potential channels. (biomedcentral.com)
  • The precise mechanism of CO2 sensing is unknown, however it has been demonstrated that CO2 and low pH inhibit a TASK-like potassium conductance, reducing potassium current. (wikipedia.org)
  • Our results indicate that T-type calcium channels are critical regulators of a C. elegans serotonergic circuit and demonstrate a mechanism in which T-type channels functionally gate inhibitory modulation in vivo . (elifesciences.org)
  • TGFβ 1 potently promotes proliferation of renal fibroblasts via a downstream mechanism that is largely mediated by bFGF ( 7 , 12 ). (pnas.org)
  • This could account for their increased evoked excitatory postsynaptic current (EPSC) delay and rise time (by about 1 ms). To test the mechanism of release protraction at brp\(^{69}\) AZs, we performed knock-down of Synaptotagmin-1 (Syt) via RNAi (syt\(^{KD}\)) in wildtype (wt), brp\(^{69}\) and rab3 null mutants (rab3\(^{rup}\)), where Brp is concentrated at a small number of AZs. (uni-wuerzburg.de)
  • In contrast to the core clock mechanism, only a small number of genes that act downstream of the clock have been identified, including pigment dispersing factor ( pdf ), pdf receptor ( pdfr ), neurofibromatosis-1 ( nf1 ), slowpoke ( slo ), narrow abdomen ( na ), and ebony [7] - [14] . (prolekare.cz)
  • The considered short- and long-range memory effects are here analyzed as they can be interpreted in terms of the complexity of the switching mechanism between stable conformational states of the channel. (bvsalud.org)
  • A Mechanism for the Activation of the Mechanosensitive Piezo1 Channel by the Small Molecule Yoda1. (psc.edu)
  • Endogenous danger signals, or damage-associated molecular patterns (DAMPs), are generated in response to cell stress and activate innate immunity to provide a pivotal mechanism by which an organism can respond to damaged self. (jci.org)
  • In the nervous system, they mediate rapid, often bi-directional, transmission of signals through channels called innexins in invertebrates and connexins in vertebrates. (biologists.org)
  • Polyamines are known to inhibit nonselective cation channels that mediate the generation of mIcat. (bvsalud.org)
  • A key question in AD is the transition from controlled to compulsive drinking, and development of dependence may be related not only to gene expression modulated through transcriptional regulation but also through alternative splicing of genes, which may produce functionally distinct isoforms. (mdpi.com)
  • We developed a multiscale neocortical model proceeding from the molecular to the network level to assess the contributions of calcium regulation of hyperpolarization-activated cyclic nucleotide-gated (HCN) channels in providing additional and complementary support of continuing activation in the network. (yale.edu)
  • The predominant physiological function of mitochondria is the generation of ATP by oxidative phosphorylation, but additional functions include the generation and detoxification of reactive oxygen species, involvement in some forms of apoptosis, regulation of cytoplasmic and mitochondrial matrix calcium, synthesis and catabolism of metabolites and the transport of the organelles themselves to correct locations within the cell. (biochemj.org)
  • Our results provide evidence that global down-regulation of TREK-1 channels has dual effects on detrusor contractility and micturition patterns in vivo. (biomedcentral.com)
  • The observed differences are likely due to expression of TREK-1 channel not only in detrusor myocytes but also in afferent and efferent neural pathways involved in regulation of micturition which may underly the "mixed" voiding phenotype in TREK-1 KO mice. (biomedcentral.com)
  • Over time, the neuron adjusts its intrinsic maximal conductances to produce a stable bursting activity pattern (3rd panel from the top). (scholarpedia.org)
  • That is, we investigate how different alignments of synchronous pauses in synthetic Purkinje neuron spike trains affect either time-locking or rate-changes in the downstream nuclei. (yale.edu)
  • This is the GENESIS 2.3 implementation of a multi-compartmental deep cerebellar nucleus (DCN) neuron model with a full dendritic morphology and appropriate active conductances. (yale.edu)
  • The Gβγ subunit activated by G i/o -coupled GPCRs can inhibit this process by interacting with the SNARE protein SNAP25. (sciencemag.org)
  • This calcium signal initiates a wide spectrum of physiological responses such as muscle contraction, secretion and synaptic transmission ( Catterall, 2010 ). (frontiersin.org)
  • Pubmed ID: 14561833 Voltage-gated K+ channels localised on presynaptic nerve terminals control information coding by modulating presynaptic firing and synaptic efficacy in target neurones. (jove.com)
  • Ca(2+)-activated K(+) channels (BK and SK) are ubiquitous in synaptic circuits, but their role in network adaptation and sensory perception remains largely unknown. (sdbonline.org)
  • We then examined how inhibitory and excitatory synaptic input interacted with these intrinsic conductances to control DCN firing. (yale.edu)
  • Fast rebound bursts due to T-type calcium current and slow rebounds due to persistent sodium current could be differentially regulated by synaptic input, and the pattern of these rebounds was further influenced by HCN current. (yale.edu)
  • While IS3 cell morphology and synaptic output have been examined, their voltage-gated ion channel profile and distribution remain unknown. (eneuro.org)
  • 2020. "Electromechanical Coupling in the Hyperpolarization-Activated K+ Channel KAT1. (psc.edu)
  • 2020. "Selectivity Filter Modalities and Rapid Inactivation of the HERG1 Channel. (psc.edu)
  • 2020. "Crowding, Sticking, and Partial Folding of GTT WW Domain in a Small Cytoplasm Model. (psc.edu)
  • 11 , 12 We hypothesized that H 2 O 2 is indeed released from the endothelium and is the transferrable agent that diffuses to the smooth muscle to elicit hyperpolarization by opening K + channels, with resultant vasodilation. (ahajournals.org)
  • V mem hyperpolarization was transduced into downstream events via V mem -regulated activity of SLC5A8, a sodium-butyrate exchanger previously implicated in human cancer. (biologists.org)
  • A role for the "energy sensor" AMP-activated protein kinase (AMPK) has also been proposed in hypoxia sensing. (wikipedia.org)
  • Inhibitors and activators were used to characterize the involvement of nitric oxide, soluble guanylate cyclase, cyclic GMP, protein kinase G and BKCa channel. (ufl.edu)
  • History To clarify the role of angiotensin II (Ang II) in insulin-induced arteriosclerosis we examined the effects of Ang II on insulin-induced mitogen-activated protein (MAP) kinase activation and cellular hypertrophy in rat vascular smooth muscle cells (VSMCs). (bio-aromatica.com)
  • The expressed a subunit reconstituted alone did not generate functional cGMP-gated channels. (ubc.ca)
  • However, so far it is still not known whether the functional properties of remaining (non-internalized) receptor/channels may be regulated by internalization of the same class of receptor/channels. (springer.com)
  • Functional implications of this wound-activated bioconversion process will be discussed from the view point of chemical defense of the eukaryotic host organism by the symbiont-derived PP1/PP2A inhibitor. (biomedcentral.com)
  • Nevertheless, BK channel isoforms in different locations can exhibit functional heterogeneity mainly due to the alternative splicing during the Kcnma1 gene transcription. (bvsalud.org)
  • A decrease in functional expression of TREK-1 channel in the bladder smooth muscle was shown to be associated with detrusor overactivity (DO) in the animal model of partial bladder outlet obstruction [ 4 ]. (biomedcentral.com)
  • Openings of high-voltage-activated (HVA) calcium channels lead to a transient increase in calcium concentration that in turn activate a plethora of cellular functions, including muscle contraction, secretion and gene transcription. (frontiersin.org)
  • By genetic suppressor screening of the small-body phenotype of a cilium defective mutant, we identified a chb-3 gene. (stanford.edu)
  • Consistent with this, a gain-of-function mutation in the human β1-subunit gene (KCNMB1), involving an increase in the apparent Ca 2+ and voltage sensitivity of the channel, protected patients against diastolic hypertension. (ahajournals.org)
  • The large-conductance voltage- and Ca2+-activated K+ channels (BK) are encoded in humans by the Kcnma1 gene. (bvsalud.org)
  • The overall phenotype and bladder function were evaluated by gene and protein expression of TREK-1 channel, in vitro contractile experiments using detrusor strips in response to stretch and pharmacological stimuli, and cystometry in unanesthetized animals. (biomedcentral.com)
  • The activity-induced, calcium-dependent transcription factor, NPAS4, reduced insulin secretion and promoted β-cell health, in part through its target gene, the GTPase-activating protein RGS2. (ubc.ca)
  • Equally diverse are the physiological functions of TRP channels, in processes including taste, thermosensation, hearing, and calcium and magnesium homeostasis (for review, see Flockerzi, 2007 ). (jneurosci.org)
  • Cytosolic calcium homeostasis is pivotal for intracellular signaling and requires sensing of calcium concentrations in the cytosol and accessible stores. (plantcell.org)
  • The origin of life cannot be elucidated, without taking into consideration and explaining how the calcium signaling machinery and cell homeostasis appeared. (heavenforum.org)
  • Diabetes, a chronic metabolic disease characterized by insulin insufficiency, is linked to β-cell dysfunction with perturbed calcium homeostasis. (ubc.ca)
  • AMPK has a number of targets and it appears that, in the carotid body, when AMPK is activated by hypoxia, it leads to downstream potassium channel closure of both O2-sentive TASK-like and BK channels An increased PCO2 is detected because the CO2 diffuses into the cell, where it increases the concentration of carbonic acid and thus protons. (wikipedia.org)
  • It does this by binding various targets in the cell including a large number of enzymes, ion channels, aquaporins and other proteins. (wikipedia.org)
  • Increased intracellular Ca 2+ concentrations activate Ca 2+ -sensitive molecular targets, including endothelial nitric oxide synthase (eNOS) ( 15 ), phospholipase A 2 ( 16 ), and small- and intermediate-conductance Ca 2+ -sensitive potassium (SK and IK) channels ( 17 , 18 ). (sciencemag.org)
  • These ion channels are targets of early signaling branches and provide molecular probes to identify upstream regulators. (ucsd.edu)
  • In a gap junction, two cells are connected through channels that allow free exchange of small molecules such as ions and second messenger molecules below ∼1 kDa ( Goodenough, 1996 ). (biologists.org)
  • In order to maintain such a low cytosolic calcium concentration, Ca2+ ions thus have to be transported against a steep concentration gradient. (heavenforum.org)
  • the mitochondria are not directly accessible to the full range of substrates and inhibitors, and the complexity of cytoplasmic metabolism must be considered together with the presence of separate pools of adenine nucleotides, nicotinamide nucleotides and calcium in the cytoplasm and mitochondrial matrix. (biochemj.org)
  • To probe the physiological roles of these channels, Diana Bautista (University of California, Berkeley, Berkeley, CA) and her colleagues in David Julius' laboratory at the University of California, San Francisco (San Francisco, CA) have generated TRPM8- and TRPA1-deficient mice and have tested them in a variety of in vitro and in vivo assays. (jneurosci.org)
  • In normoxia, haem-oxygenase generates carbon monoxide (CO), CO activates the large conductance calcium-activated potassium channel, BK. (wikipedia.org)
  • This study took advantage of the large diameter of the giant fiber (GF) interneuron to map channel expression onto the axon and axon terminals of an identified interneuron. (sdbonline.org)
  • Several other proteins have been identified that associate directly with the α 1 -subunit, including calmodulin and multiple members of the small and large GTPase family. (frontiersin.org)
  • Transient receptor potential (TRP) channels comprise a large family of cation channels. (jneurosci.org)
  • We found that the GSK1016790A-induced relaxation was abolished by the NCX inhibitors KB-R7943 and LiCl but not by specific inhibitors of the Ca 2+ -activated large-, intermediate-, or small-conductance K + channels (BK Ca , IK, and SK 3 , respectively). (frontiersin.org)
  • Large conductance calcium-activated potassium channels (BK Ca ) are abundantly expressed in smooth muscle cells (SMCs) lining the blood vessel wall. (ahajournals.org)
  • The open state probability of large conductance Ca 2+ -activated K + (BK Ca ) channels in smooth muscle cells downstream from the perfusate from an endothelium-intact arteriole was examined by patch clamping. (ahajournals.org)
  • This is what Noble calls "downward causation": a causal link from a large spatial scale (the cell) to a smaller one (the molecule). (romainbrette.fr)
  • The Suction Control Pro is ideally suited for studies of mechanosensitive ion channels and for studying the effect of pressure on artificial and cellular membranes. (nanion.de)
  • In view of the importance of calcium (Ca2+) as a universal intracellular regulator, its essential role in cell signaling and communication in many biological intra and extra cellular processes, it is surprising how little it is mentioned in the origins ( evolution/ID) debate. (heavenforum.org)
  • But there is no rhythm at the molecular level, no intrinsically rhythmic molecule: it emerges by the interaction of the ionic channels, and more precisely by their interaction with the cellular environment. (romainbrette.fr)
  • Moreover, DAMPs may incite distinct downstream cellular responses that could specifically contribute to the development of allograft fibrosis and chronic graft dysfunction. (jci.org)
  • Here, we review biochemical and biophysical aspects of spontaneous and receptor-controlled electrical activity, calcium signaling, and hormone secretion in pituitary cells. (conicyt.cl)
  • Up to eight different solutions can be perfused inside the cell, allowing dose response analysis of compounds acting on the cytosolic portion of the ion channel. (nanion.de)
  • All biological cells have a low cytosolic (liquid found inside Cells ) calcium concentration, can and must keep this even when the free calcium outside is up to 20,000 times higher concentrated! (heavenforum.org)
  • The cyclic nucleotide-gated (CNG) cation channel of rod photoreceptors plays an important role in the perception of light. (ubc.ca)
  • This is the first example of reconstitution of a heterologously expressed cation channel into lipid vesicles for Ca²⁺ efflux measurements. (ubc.ca)
  • Transient receptor potential canonical 4 (TRPC4) channel is a nonselective calcium-permeable cation channels. (bvsalud.org)
  • The corresponding mutations affect the T-type calcium channel CCA-1 and symmetrically re-tune its voltage-dependencies of activation and inactivation towards more hyperpolarized potentials. (elifesciences.org)
  • During an attack, affected muscle fibers are depolarized and have reduced excitability caused by sodium channel inactivation. (rupress.org)
  • Here, we investigated the correlation between the magnitude of channel inactivation by spermine and the magnitude of channel conductance. (bvsalud.org)
  • We found that N-cyclohexyl-N-[2-(3,5-dimethyl-pyrazol-1-yl)-6-methyl-4-pyrimidinamine (CyPPA), a positive pharmacological activator of KCNN/SK/K Ca 2 channels, significantly reduced LPS-stimulated activation of microglia in a concentration-dependent manner. (elsevier.com)
  • The detrusor strips from TREK-1 KO mice also generated more contractile force in response to electric field stimulation and high potassium concentration in comparison to WT group (p ≤ 0.05 for both tests). (biomedcentral.com)
  • 100 TRP channel genes have been identified, in organisms ranging from yeast to mice, and they are divided into seven distinct subclasses based on their primary sequences. (jneurosci.org)
  • The Ca2+ channels must be positioned very close to sites of vesicle fusion, and come in diverse forms with distinct activity-dependence, responsiveness to GABA, dopamine, acetylcholine and other neuromodulators, and susceptibility to neurological disorders such as migraine, ataxia or dystonia. (stanford.edu)
  • The opening of Ca2+ channels drives at least two distinct forms of fusion. (stanford.edu)
  • The TRP domain and box, as well as slight variations of these motifs, are present in all TRPC and TRPM channel genes, but not in other TRP channels. (aspetjournals.org)
  • Each Glu residue was replaced by Gln, the modified genes were transiently expressed in loss-of-TPC1-function protoplasts, and SV channel responses to luminal calcium were recorded by patch clamp. (plantcell.org)
  • Because of the central role of TRP channels in cough response, we hypothesized that variants in genes encoding TRP channels may be associated with cough symptoms. (biomedcentral.com)
  • thus, when the AMP/ATP ratio increases AMPK becomes activated in order to rescue the energy balance. (intechopen.com)
  • Using in vivo two-photon imaging of L2 calcium signals in combination with pharmacological and genetic perturbations of these Ka channels, it was shown that the wild-type Shaker and Shal function is to enhance L2 responses and cell-autonomously sharpen L2 kinetics. (sdbonline.org)
  • 3) Results: Application of the K-nearest neighbors algorithm (KNN) and the autoencoder neural network allowed to perform the classification of the electrophysiological signals with a very good accuracy, which indicates that the conformational dynamics of the analyzed mitoBK channels from different cell types significantly differs. (bvsalud.org)
  • The obtained results suggest also that a pathological dynamics can be represented by signals of relatively low complexity (low MSE of the mitoBK channel gating in glioblastoma). (bvsalud.org)
  • Thus, somatotrophs and lactotrophs fire plateau-bursting action potentials spontaneously and without coupling to calcium release from intracellular stores, which generate calcium signals of sufficient amplitude to keep steady hormone release. (conicyt.cl)
  • These peptides are derived from various connexin sequences and have been shown to attenuate processes downstream of the putative channel activity. (physiology.org)
  • Connexin mimetic peptides are widely used to assess the contribution of nonjunctional connexin channels in several processes, including ATP release. (physiology.org)
  • A lot less is known about changes in free calcium concentrations in organelles and how these changes might affect processes in storage sites such as the vacuole. (plantcell.org)
  • In this study, we addressed the question whether KCNN/SK/K Ca 2 channels activation affected inflammatory responses of primary mouse microglial cells upon lipopolysaccharide (LPS) stimulation. (elsevier.com)
  • These findings revealed that KCNN3/SK3/K Ca 2.3 channels can modulate the LPS-induced inflammatory responses in microglial cells. (elsevier.com)
  • Thus, KCNN3/SK3/K Ca 2.3 channels may serve as a therapeutic target for reducing microglial activity and related inflammatory responses in the central nervous system. (elsevier.com)
  • This influence of target binding on Ca2+ affinity is believed to allow for Ca2+ activation of proteins that are constitutively bound to calmodulin, such as small-conductance Ca2+-activated potassium (SK) channels. (wikipedia.org)
  • Many of the proteins that calmodulin binds are unable to bind calcium themselves, and use calmodulin as a calcium sensor and signal transducer. (wikipedia.org)
  • More strikingly, most of the α 1 -subunit interacting proteins, such as the β-subunit and small GTPases, regulate both gating and trafficking through a variety of mechanisms. (frontiersin.org)
  • Canonical transient receptor potential (TRPC) channels have attracted attention as a key regulator of pathological phenotype switching in VSMCs. (bvsalud.org)
  • Second messengers and metabolites can also be added internally to investigate how ion channel function is affected. (nanion.de)
  • KCa3.1 channels expression and cell localization in the brain of pMCAO mice model were measured by immunoblotting and immunostaining. (biomedcentral.com)
  • KCa3.1 −/− mice exhibited significantly smaller infarct areas on pMCAO and improved neurological deficit. (biomedcentral.com)
  • These findings suggest that KCa3.1 channels are important in the process of stroke, and that their blockade might prove useful as therapy in stroke with upregulated KCa3.1 expression. (biomedcentral.com)
  • Despite the topographic similarities between the TRPs and the voltage-gated potassium channels, the TRPs are actually only distantly related to these channels. (aspetjournals.org)
  • In the vasculature, BK Ca operate by limiting Ca 2+ entry and arterial contraction by repolarizing SMCs and closing voltage-dependent Ca 2+ channels previously opened by pressure or vasoconstrictor agents. (ahajournals.org)
  • 150 ms making it ideal for studies of both ligand and voltage gated channels.The Temperature Control feature of the TC Flow Chamber allows experiments at hot AND cold temperatures or application of short temperature pulses. (nanion.de)
  • Importantly, this high expression level is sufficient to ascertain whether HypoPP mutant channels are leaky because of missense mutations at arginine residues in S4 segments of the voltage sensor domains. (rupress.org)
  • Voltage-gated Na + channels are involved in the generation of action potentials in excitable cells. (aspetjournals.org)
  • These factors can modulate their voltage- and Ca2+-sensitivity, and single-channel current kinetics. (bvsalud.org)
  • Voltage-gated Ca2+ channels provide the critical link between the firing of a presynaptic nerve terminal and its release of neurotransmitter. (stanford.edu)
  • When we met for the first time, he immediately asked me why I wanted to study electrical properties of gonadotrophs and gave me several reprints describing the lack of excitability of these cells and their expression of receptor-controlled and voltage-insensitive calcium channels. (conicyt.cl)
  • TRPA1 is activated by a number of environmental chemicals that induce inflammatory pain. (jneurosci.org)
  • Calmodulin can also make use of the calcium stores in the endoplasmic reticulum, and the sarcoplasmic reticulum. (wikipedia.org)
  • The diabetic myocytes also showed an increase in I NaP that was reversed by activated PI3K or PIP3. (diabetesjournals.org)
  • At millimolar concentrations, calcium competes with Mg2+ ( magnesium), binds to DNA and RNA, and clogs it up. (heavenforum.org)
  • The carotid body is a small cluster of chemoreceptor cells, and supporting sustentacular cells. (wikipedia.org)
  • Calmodulin (CaM) (an abbreviation for calcium-modulated protein) is a multifunctional intermediate calcium-binding messenger protein expressed in all eukaryotic cells. (wikipedia.org)
  • Our discussion does not cover specialized cilia in photoreceptor or olfactory cells, which express many more ion channels. (rupress.org)
  • Because vasospastic smooth muscle cells are known to be depolarized compared to controls [ 3 , 4 ], the expression and function of ion channels in these cells after SAH are of great interest. (hindawi.com)
  • Not only a powerful research tool but also ideal for educational purposes and quick tests of cells and ion channels. (nanion.de)
  • Exposure of trabecular meshwork cells to nitric oxide resulted in decreased cell volume and these decreases were abolished by ODQ and the BKCa channel inhibitor, IBTX, suggesting the involvement of soluble guanylate cyclase and K+ eflux respectively. (ufl.edu)
  • Fast-acting neurotransmitters, e.g., glutamate (excitatory) and γ-aminobutyric acid (GABA) (inhibitory), achieve effects on their target cells within one millisecond by virtue of opening ligand-operated ion channels. (sciencemag.org)
  • Expression in mammalian cells helped resolve confusion regarding the JVL of the rod CNG channel a subunit. (ubc.ca)
  • Flow induced endothelial production of H 2 O 2 , which acts as the transferrable EDHF activating BK Ca channels on the smooth muscle cells. (ahajournals.org)
  • It turns out that the differences in the mitoBK expression systems influence gating machinery by changing the scheme of switching between the stable channel conformations, and affecting the average number of available channel conformations (this effect is visible for mitoBK channels in glioblastoma cells). (bvsalud.org)
  • Stomatal closing is mediated by potassium and anion efflux from guard cells, sucrose removal, and metabolism of malate to osmotically inactive starch. (ucsd.edu)
  • During early pupal life expression of all four Shaker-related channels is markedly decreased with an almost complete shutdown of expression at early pupal stage 5 (approximately 30% through metamorphosis). (sdbonline.org)
  • In animal models, in response to subarachnoid blood, a dynamic transition of ion channel expression and function is initiated, with acute and long-term effects differing from each other. (hindawi.com)
  • Furthermore, expression patterns and function of ion channels appear to differ between main and small peripheral vessels, which may be key in understanding mechanisms behind subarachnoid hemorrhage-induced vasospasm. (hindawi.com)
  • Here, changes in calcium and potassium channel expression and function in animal models of subarachnoid hemorrhage and transient global ischemia are systematically reviewed and their clinical significance discussed. (hindawi.com)
  • The goal of the present analysis is to review ion channel expression and function in healthy cerebral blood vessels as well as after SAH. (hindawi.com)
  • Molecular and genetic approaches have demonstrated that a transcriptional negative-feedback loop lies at the heart of the clock, in which the transcription factors CLOCK and CYCLE activate expression of their own repressors, PERIOD (PER) and TIMELESS [1] . (prolekare.cz)
  • The GDF15-induced amplification of the I K is mediated by the increased expression and reduced lysosome-dependent degradation of the Kv2.1 protein, the main α-subunit of the I K channel. (biochemj.org)
  • Our previous studies confirmed that bladder capacity and detrusor relaxation in the human urinary bladder depends on the expression and function of TREK-1 channel, one of the members of the K 2P channel family [ 34 ]. (biomedcentral.com)
  • Experimental data obtained by our group in bladder specimens from patients with idiopathic DO confirmed a decreased expression of TREK-1 channels along with an altered response to pharmacological stimulation and diminished smooth muscle relaxation. (biomedcentral.com)