Effects of guanfacine monotherapy on blood pressure, heart rate, plasma renin activity, aldosterone, and catecholamines in hypertensive patients with chronic glomerulonephritis.

Effects of guanfacine, a centrally acting antihypertensive, on blood pressure, heart rate, plasma renin activity, serum aldosterone, plasma norepinephrine, and renal function were evaluated in 16 patients with hypertension with biopsy-proved chronic glomerulonephritis. Guanfacine monotherapy with a daily dose of 1 to 2.5 mg at bedtime for 6 months brought about a significant reduction in blood pressure (171 +/- 2/110 +/- 2 to 144 +/- 2/89 +/- 1 mm Hg; P less than 0.01), with concurrent decreases in heart rate (78 +/- 2 to 70 +/- 2 bpm; P less than 0.01), plasma renin activity (1.96 +/- 0.12 to 1.21 +/- 0.19 ng/ml/hr; P less than 0.05), aldosterone (14.6 +/- 1.5 to 9.7 +/- 0.9 ng/dl; P less than 0.05), plasma norepinephrine (220.5 +/- 24.2 to 132.8 +/- 27.7 pg/ml; P less than 0.05). There was no change in serum creatinine, beta 2-microglobulin, or endogenous creatinine clearance during guanfacine monotherapy. Our data suggest that guanfacine exerts its antihypertensive effect via the inhibition of sympathetic outflow and in part the suppression of the reninangiotensin-aldosterone system and that guanfacine is suitable for the effective treatment of hypertension associated with chronic glomerulonephritis.