UC Davis

Voltage-gated potassium (K_V ) channels are key regulators of vascular smooth muscle contractility and vascular tone, and thus have major influence on the microcirculation. K_V channels are important determinants of vascular smooth muscle membrane potential (E_m ). A number of K_V subunits are expressed in the plasma membrane of smooth muscle cells. Each subunit confers distinct kinetics and regulatory properties that allow for fine control of E_m to orchestrate vascular tone. Modifications in K_V subunit expression and/or channel activity can contribute to changes in vascular smooth muscle contractility in response to different stimuli and in diverse pathological conditions. Consistent with this, a number of studies suggest alterations in K_V subunit expression and/or function as underlying contributing mechanisms for small resistance artery dysfunction in pathologies such as hypertension and metabolic disorders, including diabetes. Here, we review our current knowledge on the effects of these pathologies on K_V channel expression and function in vascular smooth muscle cells, and the repercussions on (micro)vascular function.