Search results
Results from the WOW.Com Content Network
In any muscle cell, increased intracellular calcium causes contraction. In smooth muscle cells the elevated levels of intracellular calcium cause the opening of BK channels which in turn allow potassium ions to flow out of the cell. This causes further hyperpolarization and closing of voltage gated calcium channels, relaxation can then occur.
Two-pore channels (TPCs) are eukaryotic intracellular voltage-gated and ligand gated cation selective ion channels. [1] There are two known paralogs in the human genome, TPC1s and TPC2s. [2] In humans, TPC1s are sodium selective and TPC2s conduct sodium ions, calcium ions and possibly hydrogen ions. Plant TPC1s are non-selective channels.
Inward-rectifier potassium channels: These channels allow potassium ions to flow into the cell in an "inwardly rectifying" manner: potassium flows more efficiently into than out of the cell. This family is composed of 15 official and 1 unofficial member and is further subdivided into 7 subfamilies based on homology.
In addition, SK potassium channels are tightly associated with the protein calmodulin, which accounts for the calcium sensitivity of these channels. [ 9 ] [ 11 ] Calmodulin participates as a subunit of the channel itself, bound to the cytoplasmic C-terminus region of the peptide called the calmodulin binding domain (CaMBD).
Some channels conduct multiple ion currents and some are gated by multiple mechanisms. Examples of targets for modulators include: Voltage-gated ion channels. Calcium channel: see also Calcium channel blocker, Calcium channel opener; Potassium channel: see also Potassium channel blocker, Potassium channel opener
P-type calcium channel ("Purkinje") /Q-type calcium channel: HVA (high voltage activated) Ca v 2.1 : α 2 δ, β, possibly γ: Purkinje neurons in the cerebellum / Cerebellar granule cells: N-type calcium channel ("Neural"/"Non-L") HVA (high voltage activated) Ca v 2.2 : α 2 δ/β 1, β 3, β 4, possibly γ: Throughout the brain and peripheral ...
The two-pore-domain or tandem pore domain potassium channels are a family of 15 members that form what is known as leak channels which possess Goldman-Hodgkin-Katz (open) rectification. [1] These channels are regulated by several mechanisms including signaling lipids , oxygen tension , pH , mechanical stretch , and G-proteins . [ 2 ]
Potassium channel Kv1.2, structure in a membrane-like environment. Calculated hydrocarbon boundaries of the lipid bilayer are indicated by red and blue lines. Potassium channels are the most widely distributed type of ion channel found in virtually all organisms. [1] They form potassium-selective pores that span cell membranes.