Effects of vasodilating agents on the microcirculation in marginal parts of the skeletal muscle.

The present investigation was performed to gain information on the changes in the microcirculation of the skeletal muscle during the application of vasodilating agents. The flow velocity in various microvessels was measured cinematographically in isolated and non-isolated muscles of the hindlimb in cats and rats. During the intra-arterial infusion of acetylcholine (1 mug/kg times min), bradykinin (2 mug/kg times min) and isoprenaline (1 mug/kg times min) a decrease in the flow velocity up to a complete stasis was found in most of the microvessels in the marginal parts of the muscles examined. These reactions set in when the femoral flow increased and disappeared when the femoral blood flow returned to the baseline level. The experiments demonstrate that the increase in total blood flow induced by the intra-arterial infusion of vasodilating agents may be associated with a reduced perfusion of certain parts of the striated muscles.