Vasodilators and regional blood flow

Nowadays many different antihypertensive drugs are available which lower the blood pressure through various mechanisms of action. Accordingly, the haemodynamics changes that accompany the fall in blood pressure vary considerably depending upon the respective site of action of the drug and the more or less pronounced contribution of cardiovascular reflex mechaniSmS in the overall haemodynamics response. The aim of the studies described in the present thesis is to characterize and compare the haemodynam.ic profiles of various types of antihypertensive drugs with special emphasis on the drug i.nduced changes in regional blood flows. For this purpose we have used the radioactive microsphere technique to study the systermic and regional haemodynamic effects of a series of "direct" and "indirect" vasodilators in conscious hypertensive rabbits.