Interrelation of platelet aggregation, release reaction and thromboxane A2 production.
Aggregation of platelets, stimulated by different agonists, was inhibited by omitting sample stirring or by preincubation of platelets with a monoclonal antibody against glycoproteins IIb-IIIa or with a pentapeptide containing the sequence Arg-Gly-Asp-Ser. In platelets stimulated by collagen, ADP and epinephrine, the inhibition of aggregation paralleled a reduction of both release reaction and thromboxane A2 formation. When thrombin was the stimulus, ATP release and thromboxane A2 production were unaffected (or only slightly modified) by the inhibition of platelet aggregation. These data add further evidence to the hypothesis that aggregation supports the activation of platelets stimulated by weak agonists.
Balduini
C L
CL
Department of Internal Medicine, University of Pavia-IRCCS, Policlinico S. Matteo, Italy.
Bertolino
G
G
Noris
P
P
Sinigaglia
F
F
Bisio
A
A
Torti
M
M
D000244:Adenosine Diphosphate / Q000494:pharmacology; D000255:Adenosine Triphosphate / Q000097:blood*; D000911:Antibodies, Monoclonal; D001792:Blood Platelets / Q000187:drug effects / Q000378:metabolism*; D003094:Collagen / Q000494:pharmacology; D004837:Epinephrine / Q000494:pharmacology; D006801:Humans; D009842:Oligopeptides / Q000494:pharmacology; D010974:Platelet Aggregation / Q000187:drug effects; D010975:Platelet Aggregation Inhibitors; D010980:Platelet Membrane Glycoproteins / Q000276:immunology / Q000502:physiology; D013928:Thromboxane A2 / Q000096:biosynthesis*; D013929:Thromboxane B2 / Q000096:biosynthesis
D000911:Antibodies, Monoclonal; D009842:Oligopeptides; D010975:Platelet Aggregation Inhibitors; D010980:Platelet Membrane Glycoproteins; D013929:Thromboxane B2; D013928:Thromboxane A2; D000244:Adenosine Diphosphate; D000255:Adenosine Triphosphate; D003094:Collagen; C046617:arginyl-glycyl-aspartyl-serine; D004837:Epinephrine