Open AccessInhibition of Collagen- and ADP-Induced Platelet Aggregation by Substance P In Vivo
Author(s) -
Humphries Rg,
Wendy Tomlinson,
O'Connor Se,
P. Leff
Publication year - 1990
Publication title -
journal of cardiovascular pharmacology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.762
H-Index - 100
eISSN - 1533-4023
pISSN - 0160-2446
DOI - 10.1097/00005344-199008000-00016
Subject(s) - in vivo , platelet , chemistry , pharmacology , in vitro , adenosine diphosphate , adenosine , platelet adhesiveness , substance p , platelet aggregation , biochemistry , medicine , biology , receptor , microbiology and biotechnology , neuropeptide
We examined the effect of substance P, a potent stimulator of endothelium-derived relaxing factor (EDRF) release, on responses to collagen and adenosine 3',5'-diphosphate (ADP) in an in vivo model of platelet aggregation. Substance P inhibited platelet aggregation induced in vivo by both collagen and ADP. This anti-platelet effect was particularly pronounced against collagen-induced aggregation and was prevented by prior administration of haemoglobin (Hb), a known inhibitor of EDRF-mediated responses. Collagen-induced platelet aggregation in vitro was unaffected by a concentration of substance P equivalent to that achieved in plasma following in vivo administration. This study provides a clear demonstration of the anti-platelet activity of EDRF in vivo and an indication that its effectiveness may depend on the aggregating agent used.