Differential effects of vasodilators on forearm and calf vessels

Because the literature comparing the effects of vasodilators on forearm and calf vessels is very scarce, the authors compared different vasodilators used in cardiovascular medicine in a group of volunteers. The peripheral effects were measured in the sitting position by plethysmography at the calf and at the forearm. At the forearm, comparable dilator effects were seen in arteries and veins. At the calf there was a trend for arterial flow to decrease as venous capacitance increased. Vascular response seen in one limb was not representative of the whole circulation. The changes observed were dependent not only on the vascular area investigated but also on the dose used.