Effect of estrogen and angiotensin-converting enzyme inhibitor on vascular remodeling in ovariectomized spontaneously hypertensive rats.

Objective: The present study evaluated whether estrogen influences the effect of angiotensin-converting enzyme inhibition in preventing the vascular remodeling induced by hypertension and also investigated the signal mechanism involved in that effect.

Design: Ten-week-old female spontaneously hypertensive rats were ovariectomized (OVX) and randomly assigned to the groups: untreated OVX and treated with 17beta-estradiol (estradiol, 1.5 mg) and/or captopril (5 mg/kg/day).

17Beta-oestradiol enhances the acute hypotensive effect of captopril in female ovariectomized spontaneously hypertensive rats.

The objective of this study was to investigate whether the acute haemodynamic effects of angiotensin-converting enzyme inhibition with captopril could be enhanced by oestrogen administration, and then to evaluate the mechanisms involved in this enhancement. All experiments were performed in 18-week-old female spontaneously hypertensive rats arranged in three experimental groups: intact; ovariectomized (OVX); and ovariectomized plus treatment with 17beta-oestradiol (OVX + E2). These groups were used to evaluate the effects of captopril administration alone, or following bradykinin B2 receptor blockade or nitric oxide synthase inhibition, on a number of haemodynamic parameters (mean arterial pressure, cardiac index, vascular resistance and heart rate).