title: In vitro effect of endothelin-1 on collagen, and ADP-induced aggregation in human whole blood and platelet rich plasma.
abstract: The effect of ET-1 on ADP- and collagen-induced platelet aggregation in whole blood and platelet rich plasma (PRP) was studied in 39 healthy volunteers. Although ET-1 itself did not cause platelet aggregation, a marked enhancement of ADP-induced aggregation after the preincubation with ET-1 for 5 min was observed in whole blood, but not in PRP. This ET-1 concentration and preincubation time-dependent phenomenon could be demonstrated only at threshold concentrations (5 and 7.5 microM) of ADP and is probably due to an interaction of ET-1 with cells which are involved in the whole blood aggregation, such as polymorphonuclear neutrophils. In whole blood and PRP an inhibition of collagen-induced aggregation after the preincubation with ET-1 was detected. In contrast to ADP, a direct influence of ET-1 on platelet activation after the addition of collagen is therefore more likely. These results suggest that human platelets may possess ET-1 receptor(s) and that ET-1 may also interact with other blood cells.
authors.affiliation: Department of Physiology, Hamamatsu University School of Medicine, Shizuoka, Japan.
authors.forename: R
authors.initials: R
authors.lastname: Knöfler
authors.forename: T
authors.initials: T
authors.lastname: Urano
authors.forename: J
authors.initials: J
authors.lastname: Malyszko
authors.forename: Y
authors.initials: Y
authors.lastname: Takada
authors.forename: A
authors.initials: A
authors.lastname: Takada
mesh_terms: D000244:Adenosine Diphosphate / Q000494:pharmacology*; D000293:Adolescent; D000328:Adult; D001769:Blood / Q000187:drug effects*; D003094:Collagen / Q000494:pharmacology*; D004357:Drug Synergism; D016232:Endothelins / Q000494:pharmacology*; D006801:Humans; D010949:Plasma / Q000187:drug effects*; D010974:Platelet Aggregation / Q000187:drug effects*; D010976:Platelet Count
chemical_list: D016232:Endothelins; D000244:Adenosine Diphosphate; D003094:Collagen