Persistent Improvement of Cardiovascular Risk Factors in Spontaneously Hypertensive Rats Following Early Short-Term Captopril Treatment

This study was designed to determine whether an improvement in cardiovascular risk factors persists in spontaneously hypertensive rats (SHR) following withdrawal of angiotensin converting enzyme inhibitor (ACE-I) treatment. SHR were given deionized drinking water or captopril solution from four to sixteen weeks of age. At twelve weeks of age, rats from each group were instrumented with radiotelemetry devices for continuous monitoring of blood pressure. Mean arterial blood pressure was significantly lower in captopril-treated SHR during treatment (92+/-2 vs 147+/-1 mm Hg), and at twelve weeks after treatment withdrawal (131+/-2 vs 158+/-2 mm Hg). In addition, proteinuria, renal vascular resistance, plasma triglyceride levels, fasting glucose levels, post-prandial insulin levels, and heart weights were significantly reduced in the treated SHR compared to control SHR, at time-points between three to seven months after captopril withdrawal. Our findings indicate that short-term administration of an ACE-I during the developmental phase of hypertension in the SHR results in a long-term overall improvement of cardiovascular risk factors.