Renin Tachyphylaxis and ‘Renin Hypertension’ in the Rabbit

¹ From the Department of Physiology, School of Medicine, University of Southern California, Los Angeles, California

A ‘renin hypertension’ was produced by means of a constant intravenous infusion of a carefully quantitated renin solution. Renin injections were then superimposed to the point of tachyphylaxis. In all cases when tachyphylaxis was established, the blood pressure gradually returned to preinfusion levels. This occurred in spite of continuance of the renin infusion. As renin tachyphylaxis does not lower the blood pressure of renal hypertensive animals, this suggests that ‘renin hypertension’ and renal hypertension are qualitatively different entities.