Ion channels

BK channels, also called MaxiK or slo channels, are large conductance Ca2+ and voltage-activated K+ channels. They belong to a group of ion channels that when activated by membrane voltage and intracellular Ca2+, allow K+ to leave the cytoplasm. This results in hyperpolarization or a decrease in cell excitability. BK channels are essential for key physiological processes. They are particularly important for controlling the contraction of smooth muscle and in invertebrates these channels are also important for electrical tuning of hair cells in the cochlea. BK channels are important for the behavioral effects of ethanol in the worm C. elegans . ...more on Wikipedia about "BK channel"

Connexins, also known as gap junction proteins, are four-pass transmembrane proteins with cytoplasmic C and N termini. Six connexins combine together to form a hemichannel called a connexon. ...more on Wikipedia about "Connexin"

A Cyclic nucleotide-gated ion channel is any ion channel that opens in the presence of cyclic nucleotides. The channels are gated by a chemical ligand (the cyclic nucleotide) but they are more similar in structure to the family of voltage-gated ion channels than to the ligand gated ones. In fact, the cyclic nucleotide-gated channels often have positively or negatively charged areas that may respond to changes in membrane potential. The purpose and function of these charged areas are not yet fully understood. ...more on Wikipedia about "Cyclic nucleotide-gated ion channel"

Electrophysiology is the science and branch of physiology that pertains to the flow of ions in biological tissues. In particular, it encompasses the electrical recording techniques that enable the measurement of this flow and the potential changes ( signals) related to them. ...more on Wikipedia about "Electrophysiology"

G-protein coupled channels (GPC) are stimulated when the neurotransmitter binds to the G-protein coupled receptor (GCR). This activates G-proteins, which move to another ion channel. The G-Proteins allow the channel to open and ions are able to flow across the membrane. Because of the movement from the receptor to the ion, the speed of the channel opening is delayed, however the channel stays open for a longer time. ...more on Wikipedia about "G-protein-gated ion channel"

Ion channels are pore-forming proteins that help establish the small voltage gradient that exists across the membrane of all living cells (see cell potential), by allowing the flow of ions down their electrochemical gradient. They are present in the membranes that surround all biological cells. ...more on Wikipedia about "Ion channel"

The Ligand-gated ion channels, also referred to as LGICs, or ionotropic receptors, are a group of intrinsic transmembrane ion channels that are opened in response to binding of a chemical messenger, as opposed to voltage-gated ion channels or stretch-activated ion channels. ...more on Wikipedia about "Ligand-gated ion channel"

In cell biology, potassium channels are the most common type of ion channel. They form potassium-selective pores that span cell membranes. Potassium channels are found in most cells, and control the electrical excitability of the cell membrane. In neurons, they shape action potentials and set the resting membrane potential. They regulate cellular processes such as the secretion of hormones, so their malfunction can lead to diseases. ...more on Wikipedia about "Potassium channel"

Resting channels are ion channels in the plasma membrane of a cell that remain open at all times. Also called leakage channels or leak channels, resting channels allow ions to cross the membrane down their electrochemical gradient whether or not the cell is depolarized. This is in contrast to gated channels which may be either voltage-gated, ligand-gated, or stretch-gated. Unlike gated channels, which have two or three conformational states (resting, active, and sometimes inactivated), resting channels have only the open state. ...more on Wikipedia about "Resting ion channel"

Sodium channels are integral membrane proteins that exist in a cell's plasma membrane and regulate the flow of sodium (Na+) ions into it. A number of receptors function as Na+-permeable ion channels, including Acetylcholine receptors, NMDA receptors, AMPA receptors, and kainate receptors. In neuronal signalling, voltage gated sodium channels are especially important because they are responsible for a large part of the depolarization of the cell. ...more on Wikipedia about "Sodium ion channel"

Stretch-activated or stretch-gated ion channels are ion channels which open their pores in response to mechanical deformation of a neuron's plasma membrane. Though little is known about these channels, they may be linked to molecules in the cytoskeleton, which may open them by transmitting physical forces of stretch or pressure to the channels, causing them to undergo a conformational change (Kandel et al., 2000, p. 113). The channels may also be pulled open due to tension on the membrane itself (Kandel et al., 2000, p. 114). Opening the channels allows ions to which they are permeable to flow down their electrochemical gradients into or out of the cell, causing a change in membrane potential. ...more on Wikipedia about "Stretch-activated ion channel"

Voltage-dependent calcium channels (VDCC) are a group of voltage-gated ion channels found in neurons and glial cells with a permeability to the ion Ca2+, which plays a role in the membrane potential. VDCCs are involved in the release of neurotransmitters and hormones, muscular contraction, excitability of neurons and gene expression. ...more on Wikipedia about "Voltage-dependent calcium channel"

Voltage-gated ion channels are a class of trans-membrane ion channels that are activated by the surrounding potential difference near the channel (or near the cell, neuron or synapse). ...more on Wikipedia about "Voltage-gated ion channel"

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