EFFECTS OF A SINGLE-DOSE AND SHORT-TERM CAPTOPRIL TREATMENT ON SOME PRESSOR AND DEPRESSOR HUMORAL-FACTORS IN HEALTHY-SUBJECTS

14 healthy subjects (8 males and 6 females), aged 25-40 years, were st udied before and after oral administration of a single dose of 50 mg c aptopril as well as after 3 d treatment with 100 mg captopril daily pe r os. We found that in addition to the well-known effects on the renin -angiotensin-aldosterone system, captopril, after 3 d treatment, signi ficantly increases plasma and urinary kallikrein activity, plasma vaso pressin and urinary prostaglandin (PG) E(2). Atrial natriuretic peptid e did not change significantly after either the single dose or the sho rt-term treatment, We conclude that the blood pressure lowering effect of captopril could be mediated by increasing activity of the kallikre in-kinin system and of PGE(2) without any participation of atrial natr iuretic peptide.