The ganglion-blocked, angiotensin II-supported rat: a model for demonstrating antihypertensive vasodilator activity

This report describes the implementation of an in vivo method for demonstrating direct vasodilator activity of potential antihypertensive agents. The experimental model is an anesthetized, ganglion-blocked rat whose blood pressure is maintained by an intravenous infusion of angiotensin II. A hypotensive response in this model appears to correlate more closely with antihypertensive activity in desoxycorticosterone acetate (DOCA)-salt hypertensive rats than does a vasodilator response in the pump-perfused hind limb of anesthetized dogs. Furthermore, it distinguishes between vasodilators that are effective in hypertension, eg hydralazine and diazoxide, and vasodilators that are used to treat peripheral vascular disease, eg cinnarizine and papaverine.