Effects of chronic treatment with captopril (SQ 14,225), an orally active inhibitor of angiotensin I-converting enzyme, in spontaneously hypertensive rats.
The effects of hydralazine (3 mg/kg) and the angiotensin I-converting enzyme (ACE) inhibitor captopril (SQ 14,225) (100 mg/kg) on mean arterial blood pressure, plasma renin activity, urinary volume and urinary Na+,K+, and aldosterone concentrations were examined in spontaneously hypertensive rats of the Okamoto and Aoki strain (SHR) after oral daily dosing for 2 weeks, 3 or 6 months. Captopril caused progressive cumulative reductions in blood pressure resulting in normalization of pressure after 6 months of dosing. Hydralazine also significantly reduced blood pressure but not to the level of normotensive rats of the Wistar-Kyoto strain (WKY). Reductions in heart size paralleled the changes in blood pressure, normalization of cardiac hypertrophy occurring after captopril but not hydralazine. Plasma renin activity increased approximately 2-3 fold after hydralazine and 15-fold after captopril. Neither hydralazine nor captopril had any consistent effects on 24-hr urine volume, urinary Na+,K+ or aldosterone excretion. These results indicate that chronic inhibition of ACE with captopril induces normalization of blood pressure in SHR, a normal-renin model of hypertension.
D000450:Aldosterone / Q000652:urine; D000806:Angiotensin-Converting Enzyme Inhibitors; D000818:Animals; D001794:Blood Pressure / Q000187:drug effects*; D002216:Captopril / Q000008:administration & dosage* / Q000494:pharmacology; D006321:Heart / Q000033:anatomy & histology; D006973:Hypertension / Q000097:blood / Q000503:physiopathology* / Q000652:urine; D008297:Male; D009929:Organ Size / Q000187:drug effects; D011188:Potassium / Q000652:urine; D011392:Proline / Q000031:analogs & derivatives*; D051381:Rats; D012083:Renin / Q000097:blood; D012964:Sodium / Q000652:urine
D000806:Angiotensin-Converting Enzyme Inhibitors; D000450:Aldosterone; D011392:Proline; D002216:Captopril; D012964:Sodium; D012083:Renin; D011188:Potassium