Inhibition of serotonin-amplified human platelet aggregation by ketanserin, ritanserin, and the ergoline 5HT2 receptor antagonists-LY53857, sergolexole, and LY237733. Academic Article uri icon

Overview

abstract

  • Human platelets are known to possess 5HT2 receptors which, when activated, amplify the aggregation response produced by other aggregating agents. Several 5HT2 receptor antagonists, including ketanserin and ritanserin, are known to antagonize serotonin-mediated aggregation of human platelets. In the present study, we document the ability of three ergoline 5HT2 receptor antagonists, LY53857, sergolexole, and LY237733, to antagonize the serotonergic component of the human platelet aggregation response. Potencies of the ergoline esters (LY53857 and sergolexole) and the ergoline amide (LY237733) to inhibit serotonin-amplified platelet aggregation responses were similar to the potencies of ketanserin and ritanserin under the conditions of our study. Furthermore, all five 5HT2 receptor antagonists were capable of fully inhibiting the serotonergic component of the platelet aggregation response. In contrast to these potent ergoline esters and amides, 1-isopropyl dihydrolysergic acid (up to 10(-5)M), a putative metabolite of the ergoline esters, was ineffective under these in vitro conditions. These data are consistent with the high potency of these ergolines as antagonists of 5HT2 receptors and further support the involvement of 5HT2 receptors on human platelets in the amplifying response to serotonin.

publication date

  • January 1, 1990

Research

keywords

  • Platelet Aggregation
  • Platelet Aggregation Inhibitors
  • Receptors, Serotonin
  • Serotonin Antagonists

Identity

Scopus Document Identifier

  • 0025672597

Digital Object Identifier (DOI)

  • 10.1016/0024-3205(90)90307-d

PubMed ID

  • 2125095

Additional Document Info

volume

  • 47

issue

  • 23