Potassium channel activation improves blood flow pattern of conscious rats in cutaneous microcirculation

A dose-dependent mean arterial blood pressure reduction (tailcuff method) to an intravenously administered potassium channel activator was found in conscious rats. Intravital microscopic analysis of skin microcirculation in conscious rats was performed with respect to erythrocyte flow velocity and diameters of capillaries. There was a dose-dependent increase of erythrocyte flow velocity; diameters of capillaries were dilated following a dosage of 6 and 12 Myg/kg bw, but constricted following a dosage of 24 Myg/kg bw. Frequency distributions of velocity ranges in capillaries under observation (real time video recordings) proved that the increase of microvascular perfusion is manifested by a shift of maximal values to increasing velocity ranges. It is concluded that potassium channel activation plays an important role in the local regulation of perfusion on the peripheral circulation.