Does captopril lower blood pressure in anephric patients?

Captopril inhibits peptidyldipeptide hydrolase, the enzyme that converts angiotensin I to angiotensin II and degrades bradykinin. Captopril's antihypertensive action seems to depend on the activity of the renin-angiotensin system in relation to the state of sodium balance.'-3 It is not clear, particularly in patients with normal or low plasma renin activity, whether captopril lowers blood pressure by eliminating the vasoconstrictor angiotensin II or by allowing the vasodilator bradykinin to accumulate. We have studied captopril's effect on supine and standing blood pressure in an anephric woman in three different states of sodium balance.