calcium channel


Also found in: Dictionary, Thesaurus, Legal, Financial, Encyclopedia, Wikipedia.
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 ?
Calcium Channel Blockers' Action on Calcium Channels.
Calcium channel blockers also increase the supply of oxygen-rich blood to your heart, which is known as the "negative inotropic effect" (decreased force of heart contraction).
Calcium channel expression also changes with normal aging.
Several recent large meta-analyses indicate that although calcium channel blockers and diuretics reduce blood pressure variability, beta-blockers, angiotensin receptor blockers, and ACE inhibitors actually increase it, he continued.
Jaroslaw Dziegielewski of the University of Virginia will present his late-breaking results entitled "Targeting T-type Calcium Channels Induces the Extrinsic Apoptotic Pathway and Sensitizes Glioblastoma Cancer Cells to Radio- and Chemotherapy.
The decision by scientific advisers to the Food and Drug Administration should help settle intense controversy about a class of blood pressure drugs called calcium channel blockers.
The calcium channel is actually present throughout the entire brain", explains Mark.
We studied this years ago and found that calcium channel blockers helped alleviate any blood pressure-associated change with nonsteroidal anti-inflammatory drugs," Dr.
Neuromed is the only company in the world with a sole focus on target- specific calcium channel drugs to treat chronic pain, anxiety, epilepsy and cardiovascular disease.
In a registry that enrolled 1,360 PAH patients, 31% were on calcium channel blockers at the time of referral to a tertiary care center (Eur.
Tau Therapeutics is a clinical stage company developing oncology drugs for solid tumors that selectively inhibit the T-type calcium channel - a novel mechanism of action for cancer.
The risk of developing cancer was 72 percent higher among those who used the short-acting forms of calcium channel blockers in the study by a team led by Dr.

Full browser ?