SKA-31. A Potent Activator of KCa3.1 and KCa2 Channels.
Ca2+-activated potassium channels (KCa) are a group of 6/7-TM�proteins that selectively transport K+ ions across biological membranes. They are broadly classified into three subtypes: SK, IK and BK channels (small, intermediate and big conductance, respectively).
The three small-conductance Ca2+-activated K+ channels KCa2.1 (SK1), KCa2.2 (SK2), and KCa2.3 (SK3), and the intermediate-conductance KCa3.1 channel (IK1, SK4) play important roles in various physiological functions by modulating Ca2+-signaling cascades and regulating membrane potential, in the CNS and also peripherally.
Outside of the nervous system KCa2 channels, especially KCa2.3, are involved in blood pressure regulation, contractility of urinary bladder smooth muscle and metabolism. Like KCa2.3, KCa3.1 is further expressed in vascular endothelium and contributes to blood pressure control by initiating the so-called endothelium derived hyperpolarizing factor (EDHF) response, a nitric oxide and prostacyclin independent component of endothelium-dependent relaxation.
SKA-31 is an activator of KCa3.1 and KCa2 channels (EC50 values are 260, 2900, 2900, 1900 nM for KCa3.1, KCa2.1, KCa2.3 and KCa2.2 respectively). It potentiates acetylcholine-induced EDHF-type dilations of mouse carotid arteries and lowers blood pressure in normotensive and hypertensive mice, by 4-6 and 12 mmHg, respectively.
Ion Channel Modulators; K+ Channel Openers