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PubMed · 6822293

5-hydroxytryptamine and platelet aggregation.

F F De Clerck·A G Herman
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Abstract

5-Hydroxytryptamine (5-HT) activates blood platelets of various species including humans. In contrast to cat, pig, and sheep platelets, human blood platelets respond to 5-HT mainly with a shape change and a reversible aggregation only. However, depending on the concentration and the time interval between its addition and that of another agonist, 5-HT amplifies the human platelet aggregation induced by ADP, collagen, epinephrine, and norepinephrine; the monoamine itself induces strong aggregation of platelets presensitized with norepinephrine, lysolecithin, or Thrombofax. Prolonged exposure of platelets to 5-HT results in transient tachyphylaxis. Pharmacodissection and receptor-binding studies suggest the presence of functional receptors, possibly of the 5-HT2 (S2) type, different from the ones involved in the active uptake of the monoamine by the platelets. As a modulator of platelet reactions, 5-HT may be involved in secondary platelet aggregation, hemostasis, and thrombus formation.

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Adenosine DiphosphateAnimalsBrainDose-Response Relationship, DrugHumansPlatelet AggregationReceptors, SerotoninSerotoninSpecies SpecificityJournal ArticleResearch Support, Non-U.S. Gov't

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F F De Clerck, A G Herman. 1983. 5-hydroxytryptamine and platelet aggregation.. https://pubmed.ncbi.nlm.nih.gov/6822293/

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