Haemodynamic resistance of forearm vessels during prolonged drug treatment of essential hypertension.

In 40 patients with essential hypertension, the authors studied the haemodynamic resistance in forearm vessels before and after 15-min arterial occlusion, and changes in this parameter during a three-year combined antihypertensive treatment. The study revealed that the 15-min occlusion did not entirely suppress the contractile activity of vascular smooth muscles. Under these conditions, the minimum vascular resistance reflects the sum of structural and functional alterations. The character of change in minimal haemodynamic vascular resistance depends on the mechanism of action of the antihypertensive drugs. Administration of the post-synaptic alpha-adrenergic blocker Pratsiol produces a decrease in the minimal haemodynamic vascular resistance.