KV channels and the regulation of vascular smooth muscle tone.

VSMCs in resistance arteries and arterioles express a diverse array of KV channels with members of the KV 1, KV 2 and KV 7 families being particularly important. Members of the KV channel family: (i) are highly expressed in VSMCs; (ii) are active at the resting membrane potential of VSMCs in vivo (-45 to -30 mV); (iii) contribute to the negative feedback regulation of VSMC membrane potential and myogenic tone; (iv) are activated by cAMP-related vasodilators, hydrogen sulfide and hydrogen peroxide; (v) are inhibited by increases in intracellular Ca2+ and vasoconstrictors that signal through Gq -coupled receptors; (vi) are involved in the proliferative phenotype of VSMCs; and (vii) are modulated by diseases such as hypertension, obesity, the metabolic syndrome and diabetes. Thus, KV channels participate in every aspect of the regulation of VSMC function in both health and disease.