Abstract
We have studied the effects of treatment for one month with perindopril, 4 or 8 mg once daily, in seven hypertensive patients. Blood pressure was lowered from 164/93 mm Hg to 145/84 mm Hg by 4 mg of perindopril and after one month remained at 142/82 mm Hg. Neither postural hypotension nor tachycardia occurred. Inhibition of plasma angiotensin converting enzyme (ACE) lasting for over 24 h was achieved and there was a significant increase in plasma renin activity (PRA). Maximum plasma concentrations of the active metabolite of perindopril, S-9780, were detected four h after oral administration. After treatment for one month there was evidence of reduced sensitivity of plasma ACE to the action of the inhibitor. The plasma concentration of S-9780 required to produce 50% inhibition of plasma ACE rose from 2.4 ng · ml−1 following the first dose to 5.5 ng · ml−1 after one month.