The effect of ketanserin, a 5-HT2-receptor antagonist, on 5-hydroxytryptamine-induced irreversible platelet aggregation in patients with cardiovascular diseases

Abstract

Platelet aggregation in response to 5-hydroxytryptamine was investigated in 40 normal subjects, in 45 patients with acute myocardial infarction, and in 65 patients with peripheral arterial obstructive disease. It was found that of the 110 patients with cardiovascular disease, 40% had a biphasic irreversible platelet aggregation, whereas this phenomenon occurred in only 7.5% of the normal population. A double-blind placebo-controlled study further showed that a subacute treatment with ketanserin, a selective 5-HT2-receptor antagonist both on platelets and on vascular tissue, efficiently abolished the irreversible platelet aggregation in patients hyperreactive to 5-hydroxytryptamine. In an additional open study, including 10 patients with peripheral arterial obstructive disease, a chronic treatment with ketanserin 40 mg t.i.d. for a period of 3 months significantly suppressed the primary platelet aggregation to 5-HT at 2 X 10(-5) M and at 2 X 10(-6) M and significantly lowered the plasma beta thromboglobulin levels. Since 5-HT is a potent mediator of vasospasm, treatment with ketanserin might be of therapeutic value in atherosclerotic diseases, where platelet activation is thought to be involved.

Effects of ketanserin, a selective 5-HT2 serotonergic antagonist, on the secondary recruitment of human plateletsin vitro

“…As a whole, our experiments demonstrate that ketanserin, in particular conditions, is able to reduce the second wave of aggregation induced The observation that in some cardiovascular patients treated with the drug the increased plasma beta-thromboglobulin levels are reduced after treatment [33][34][35] suggests that ketanserin, possibly through the above described mechanism, is also able to reduce the release of vasoactive products by the platelets in vivo.…”