calcium channel


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Related to calcium channel: Calcium channel blockers

channel

 [chan´el]
a passage, cut, or groove through which something can pass or flow across a solid structure.
calcium channel (calcium-sodium channel) a slow voltage-gated channel very permeable to calcium ions and slightly permeable to sodium ions, existing in three subtypes designated L, M, and N and located throughout the body; calcium channels are the main cause of action potentials in certain smooth muscles, and the N channels regulate neurotransmitter release.
fast channel a protein channel, such as a sodium channel, that becomes activated relatively quickly; a fast voltage-gated channel has a much lower activation potential than does the slow type. See also slow channel.
ligand-gated channel a protein channel that opens in response to the binding of a molecule (the ligand) to the protein, which causes a conformational change in the protein molecule. See also voltage-gated channel.
potassium channel a slow voltage-gated channel selective for the passage of potassium ions, found on the surface of a wide variety of cells, including nerve, muscle, and secretory cells; its functions include regulation of cell membrane excitability, regulation of repetitive low frequency firing in some neurons, and recovery of the nerve fiber membrane at the end of the action potential.
protein channel a watery pathway through the interstices of a protein molecule by which ions and small molecules can cross a membrane into or out of a cell by diffusion; protein channels play a vital role in depolarization and repolarization of nerve and muscle fibers, and may have physical characteristics such as shape or diameter that particularly attract certain ions.
slow channel a protein channel such as the calcium channel that is slow to become activated; a slow voltage-gated channel has a much higher activation potential than does the fast type. See also fast channel.
sodium channel a type of fast channel selective for the passage of sodium ions. Voltage-gated sodium channels are the main causes of depolarization and repolarization of nerve membranes during the action potential. In cardiac cells they produce phase 0 of the action potential.
voltage-gated channel a protein channel that can be opened or closed in response to changes in the electric potential across a cell membrane. See also ligand-gated channel.
water channel a channel in a cell membrane that permits passage of water molecules; chemical substances such as vasopressin cause the opening of new channels and increase permeability.

calcium channel

a slow voltage-gated channel very permeable to calcium ions and slightly permeable to sodium ions, existing in three subtypes designated L, M, and N and located throughout the body. In excitable cells the action potential results from the transmembrane fluxes of Na+, Ca2, and K+. Calcium channels are the main cause of action potentials in certain smooth muscles, and the N channels regulate neurotransmitter release. Also called calcium-sodium channel.

calcium channel

A family of transmembrane ion channels—most of which are voltage-gated, some of which are ligand-gated—which release Ca2+from stores in skeletal muscle, cardiac muscle, bone and neurones.
References in periodicals archive ?
6 Calcium channel blockers may cause vasculitis as their side effect.
Aside from standard cardiopulmonary measures in calcium channel blocker overdoses, additional commonly employed resuscitative therapies have included gastric lavage, multi-dose oral or nasogastric activated charcoal, flumazenil infusion, naloxone infusion, insulin and glucagon intravenous boluses, continuous calcium gluconate infusion, intravenous antiarrhythmics as indicated, and vasopressor support during mechanical ventilation.
This study was planned to evaluate the effects of extract from the fruits of Ammi visnaga having documented natural calcium blocker and Verapamil which is also a calcium channel blocker, on the volume and acidity of Carbachol induced gastric secretion.
Gastric lavage should be performed and active charcoal should be given to decrease the absorption of the drug and increase excretion for treatment of calcium channel blocker intoxication.
Prostaglandin inhibitors and calcium channel blockers delay delivery and improve short-term neonatal outcomes
The role of insulin and glucose (hyperinsulinemia/euglycemia) therapy in acute calcium channel antagonist and beta blocker poisoning.
Inhibitory action of a calcium channel blocker (nimodipine) on seizure and brain damage induced by pilocarpine and lithium-pilocarpine in rats.
In addition to reducing stroke risk, calcium channel blockers may also have a neuroprotective effect.
So if your doctor prescribes an ACE inhibitor or calcium channel blocker, ask for a diuretic instead.
In 2002 researchers reported that among patients followed for four to eight years the diuretic was better than the calcium channel blocker in preventing heart failure and better than the ACE inhibitor in preventing stroke, heart failure and overall cardiovascular disease.
The aberrant calcium channel protein that causes this type of night blindness is missing the tail end of the protein.
Whitehouse Station, NJ) will terminate the research collaboration and license agreement for novel compounds targeting N-type calcium channels for the treatment of pain and other disorders, which the companies entered into in March of 2006.

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