K2Pkanaler

K2P-kanaler, eller två-pore-domain potassium channels, are a family of potassium-selective ion channels characterized by four transmembrane segments and two pore-forming P domains in each subunit. Two subunits assemble as dimers to form functional leak channels that conduct potassium ions and contribute to background currents. Their activity helps set and stabilize the resting membrane potential and thereby regulates cellular excitability in neurons, glia, muscle cells and other tissues.

These channels are distinct from voltage-gated potassium channels in that they are largely voltage-insensitive and often provide constitutive ("leak") currents. Their gating and conductance are modulated by a variety of stimuli, including extracellular and intracellular pH, mechanical stretch, temperature, and lipid signaling molecules such as arachidonic acid and PIP2. In addition, G protein–coupled receptor signaling can influence their activity, linking cellular signaling pathways to changes in excitability.

K2P channels are divided into several subfamilies, including TWIK, TREK (and TRAAK), TASK, TALK, THIK, and TRESK, each containing multiple members. Representative members include TWIK-1, TREK-1, TREK-2, TRAAK, TASK-1, TASK-3, TALK-1, TALK-2 and TRESK. These channels are widely expressed in the central and peripheral nervous system, heart, and other organs, where they shape neuronal firing, sensory perception, cardiac rhythm, and other physiological processes.

Clinical and pharmacological interest in K2P channels centers on their potential as targets for analgesia, anesthesia and mood or cognitive disorders, as well as their involvement in various neuropathological states. Ongoing research seeks to understand their exact roles in health and disease and to identify selective modulators.