We compared the effects of angiotensin-converting enzyme inhibition with quinapril to those of selective beta-blockade with atenolol and calcium channel blockade with verapamil in 10 hypertensive subjects in a randomized double-blind placebo-controlled crossover study. All antihypertensive agents reduced baseline mean arterial pressure equally and did not modify forearm vascular resistance compared to placebo. In response to sustained handgrip exercise, both quinapril and verapamil, but not atenolol, attenuated the pressor response. However, verapamil was associated with an exaggerated increase in forearm vascular resistance during handgrip, whereas quinapril did not alter this response compared to placebo. It is concluded that quinapril and verapamil reduce the pressor response during isometric exercise by quantitatively different effects on the vasoconstrictor response in, as well as outside of, skeletal muscles.