Comparative effects of antihypertensive therapy with guanabenz and propranolol on renal vascular resistance and left ventricular mass.

There is increasing interest in initial therapy of hypertension with sympatholytic agents and the influence of antihypertensive therapy on cardiac and renal function. We treated 26 men with essential hypertension with either guanabenz alone (n = 14) or propranolol alone (n = 12) and assessed blood pressure and renal perfusion before and after 5-7 weeks of treatment. Cardiac performance was evaluated for the guanabenz-treated patients. Both drugs substantially reduced blood pressure without weight gain. During guanabenz therapy, glomerular filtration rate and renal blood flow were preserved, with a fall in renal vascular resistance (from 12,100 +/- 1,500 to 9,300 +/- 1,190 dyne X s X cm-5, p less than 0.01). Propranolol decreased glomerular filtration rate (from 95 +/- 11 to 70 +/- 6 ml/min, p less than 0.05) without significant change in renal blood flow or renal vascular resistance. In guanabenz-treated patients, there was a decline in left ventricular mass (from 290 +/- 23 to 257 +/- 14 g, p = 0.067). Thus, both agents are effective initial therapy in hypertension. Guanabenz treatment also was associated with reduced renal vascular resistance and left ventricular mass.