title: Involvement of 5-hydroxytryptamine in platelet aggregation in vivo in rats and guinea pigs.
abstract: In this study, 5-hydroxytryptamine (5-HT) caused a dose-dependent fall in the circulating platelet count suggesting that 5-HT receptors are activated in rat platelets to cause platelet adhesion and aggregation. When low doses of adenosine diphosphate (ADP) were simultaneously injected with 5-HT, there was a significant potentiation of the responses to ADP. Ketanserin significantly reduced the potentiated responses. When higher doses of ADP were infused with bolus injections of 5-HT there was no potentiation and ketanserin did not reduce these responses. Ketanserin did not inhibit the collagen-induced fall in circulating platelet count, but did significantly increase the rate of return to the basal platelet count compared with control. 5-HT did not cause a fall in platelet count in guinea-pigs.
authors: School of Pharmacy, Robert Gordon's Institute of Technology, Aberdeen, Great Britain.
authors: G M
authors: GM
authors: Smith
mesh_terms: D000244:Adenosine Diphosphate / Q000502:physiology; D000818:Animals; D002997:Clomipramine / Q000494:pharmacology; D003094:Collagen / Q000502:physiology; D004357:Drug Synergism; D006168:Guinea Pigs; D007650:Ketanserin / Q000494:pharmacology; D008297:Male; D010974:Platelet Aggregation / Q000187:drug effects; D010976:Platelet Count / Q000187:drug effects; D051381:Rats; D011919:Rats, Inbred Strains; D012701:Serotonin / Q000008:administration & dosage / Q000502:physiology*
chemical_list: D012701:Serotonin; D000244:Adenosine Diphosphate; D003094:Collagen; D007650:Ketanserin; D002997:Clomipramine