Degenerin Sodium Channels
A family of mechanosensitive sodium channels found primarily in NEMATODES where they play a role in CELLULAR MECHANOTRANSDUCTION. Degenerin sodium channels are structurally-related to EPITHELIAL SODIUM CHANNELS and are named after the fact that loss of their activity results in cellular degeneration.
Sodium Channels
Epithelial Sodium Channels
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.
Acid Sensing Ion Channels
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.
Sodium Channel Blockers
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.
Ion Channels
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.
Sodium Channel Agonists
A class of drugs that stimulate sodium influx through cell membrane channels.
Sodium
Ion Channel Gating
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.
Amiloride
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)
NAV1.5 Voltage-Gated Sodium Channel
NAV1.2 Voltage-Gated Sodium Channel
A voltage-gated sodium channel subtype that mediates the sodium ion permeability of excitable membranes. Defects in the SCN2A gene which codes for the alpha subunit of this sodium channel are associated with benign familial infantile seizures type 3, and early infantile epileptic encephalopathy type 11.
NAV1.6 Voltage-Gated Sodium Channel
Calcium Channels
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 Sodium Channels
NAV1.8 Voltage-Gated Sodium Channel
A voltage-gated sodium channel subtype that is expressed in nociceptors, including spinal and trigeminal sensory neurons. It plays a role in the transmission of pain signals induced by cold, heat, and mechanical stimuli.
NAV1.1 Voltage-Gated Sodium Channel
A voltage-gated sodium channel subtype that is predominantly expressed in the CENTRAL NERVOUS SYSTEM. Defects in the SCN1A gene which codes for the alpha subunit of this sodium channel are associated with DRAVET SYNDROME, generalized epilepsy with febrile seizures plus, type 2 (GEFS+2), and familial hemiplegic migraine type 3.
Mechanotransduction, Cellular
NAV1.7 Voltage-Gated Sodium Channel
NAV1.4 Voltage-Gated Sodium Channel
Nerve Tissue Proteins
'Nerve tissue proteins' are specialized proteins found within the nervous system's biological tissue, including neurofilaments, neuronal cytoskeletal proteins, and neural cell adhesion molecules, which facilitate structural support, intracellular communication, and synaptic connectivity essential for proper neurological function.
Saxitoxin
A compound that contains a reduced purine ring system but is not biosynthetically related to the purine alkaloids. It is a poison found in certain edible mollusks at certain times; elaborated by GONYAULAX and consumed by mollusks, fishes, etc. without ill effects. It is neurotoxic and causes RESPIRATORY PARALYSIS and other effects in MAMMALS, known as paralytic SHELLFISH poisoning.
Potassium Channels, Inwardly Rectifying
Oocytes
Batrachotoxins
NAV1.3 Voltage-Gated Sodium Channel
Calcium Channel Blockers
Tetrodotoxin
Potassium Channel Blockers
Chloride Channels
Electrophysiology
Voltage-Gated Sodium Channel Blockers
Scorpion Venoms
Membrane Potentials
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).
NAV1.9 Voltage-Gated Sodium Channel
A voltage-gated sodium channel subtype found in the neurons of the NERVOUS SYSTEM and DORSAL ROOT GANGLIA. It may play a role in the generation of heat and mechanical pain hypersensitivity.
Potassium Channels, Voltage-Gated
Molecular Sequence Data
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.
Veratridine
A benzoate-cevane found in VERATRUM and Schoenocaulon. It activates SODIUM CHANNELS to stay open longer than normal.
Voltage-Gated Sodium Channel beta-1 Subunit
A voltage-gated sodium channel beta subunit abundantly expressed in SKELETAL MUSCLE; HEART; and BRAIN. It non-covalently associates with voltage-gated alpha subunits. Defects in the SCN1B gene, which codes for this beta subunit, are associated with generalized epilepsy with febrile seizures plus, type 1, and Brugada syndrome 5.
Patch-Clamp Techniques
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.
Calcium Channels, L-Type
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.
Caenorhabditis elegans
Epithelial Sodium Channel Blockers
KATP Channels
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.