[Influence of chronic ketanserin therapy on blood pressure and certain humoral and metabolic factors in patients with mild to moderate primary essential hypertension].

Ketanserin, a serotonin-2-receptor antagonist, was administered to 16 patients with mild to moderate essential hypertension in randomized single-blind placebo controlled study. After 2 weeks of placebo administration ketanserin 60 mg daily was given for 3 weeks. In 7 patients the normalization of blood pressure was obtained and they were given the same daily dose of ketanserin for another 3 weeks. In the remaining 9 patients the dose of ketanserin was increased to 120 mg daily for the same period; in one additional case blood pressure decreased to normal. In the whole group the decrease of diastolic pressure was statistically significant comparing to placebo period. Ketanserin therapy did not influence serum free serotonin concentration, but the hypotensive effect was greater in patients with lower serotonin blood levels. Serum aldosterone concentration decreased in the initial period of treatment; the decrease was more pronounced in patients who responded to therapy. In this subgroup of patients diastolic blood pressure correlated positively with plasma renin activity. Ketanserin lowered serum adrenaline concentration, particularly in patients with good response to therapy. There was also decrease of total cholesterol concentration without any significant changes in HDL--cholesterol fraction. The authors conclude that oral chronic ketanserin treatment is an effective therapy in essential hypertension and that its effectiveness is greater in patients with lower serum serotonin levels. The hypotensive effect of the drug may be connected with lower sympathetic activity and with changes in renin-angiotensin-aldosterone system. Ketanserin is well tolerated and exerts beneficial effect on lipid metabolism.