ABSTRACT
Terazosin is an alpha 1 blocker indicated in therapy of mild to moderate hypertension, in peripheral vascular disease and in cases of refractory congestive heart failure. It is also used in benign prostatic hypertrophy. The present study was designed to investigate the effects of terazosin on blood pressure, renal blood flow parameters, insulin resistance, blood glucose, cholesterol and triglycerides in rats. Insulin resistance was induced experimentally by feeding rats l0% fructose in drinking water for 4 weeks. In vitro studies done to investigate terazosin site of action. In-vivo studies, terazosin significantly decreased systolic and mean arterial blood pressure and serum cholesterol but triglycerides showed insignificant change. Terazosin significantly improved insulin sensitivity. Doppler technique showed that Terazosin significantly decreased renal artery systolic pressure and blood flow velocity while it produced insignificant effect on heart rate. In-vitro studies on isolated rat aorta and isolated rat heart, terazosin had a significant cholinomimetic effect beside it's alpha 1 blocking action