Chronic effects of serotonin inhibition in hypertensive patients: hemodynamic and humoral findings.

This review deals with the effects of chronic antihypertensive treatment with ketanserin on a series of physiological and biochemical variables, both at rest and during stimulation (exercise or stress). In four centers, different aspects were covered, with blood pressure as the common denominator in 45 hypertensive patients. Treatment periods ran from 1 to 9 months with daily doses ranging from 80 to 160 mg. Systolic and diastolic pressures fell roughly by 10 mm Hg. Heart rate tended to be reduced. The decrease in blood pressure was accounted for mainly by a decrease in calculated total peripheral (and renal) vascular resistance. Volume parameters failed to show statistically significant changes, although plasma volume tended to expand. The profile of hemodynamics during exercise was basically unmodified. Hormonal changes were not uniform, but the main trend was a decrease in the activities of both the renin-angiotensin and the adrenergic system. Apparently the action of ketanserin is not confined to 5-HT2-serotonergic blockade.