Effect of beta-adrenoreceptor blockade on the renin response to acute natriuresis.

1. The response of plasma renin activity to frusemide 40 mg given intravenously, was examined before and after oral propranolol 160 mg daily for 7 days in normal and hypertensive subjects. 2. Although basal renin levels were often reduced, the increase following frusemide was essentially unaltered by propranolol therapy. 3. These findings indicate that enhanced renin activity associated with diuretic use may not be prevented by concurrent propranolol administration. Limitation of hypotensive action of combined beta-blocker diuretic therapy can therefore be anticipated. 4. Preservation of the renin stimulatory effect of frusemide during beta blockade confirms the value of this procedure in the investigation of mineralocorticoid and renovascular hypertension were discontinuation of treatment may be undesirable.