The role of prostaglandins in the ADP-induced aggregation of rabbit platelets shown by the use of 15-hydroxyprostaglandin dehydrogenase.
The initial shape change and subsequent aggregation of platelets in citrated rabbit platelet-rich plasma caused by ADP in vitro was inhibited by 15-hydroxyprostaglandin dehydrogenase. This inhibition was NAD-dependent and was also seen when shape change and aggregation were initiated by sodium arachidonate or by collagen. The aggregation of gel-filtered rabbit platelets by thrombin was not, however, affected by removal of 15-hydroxyprostaglandins. Indomethacin was found to inhibit ADP-induced aggregation but at a concentration (250 micron) much higher than that required to inhibit collagen-induced aggregation. Moreover the platelet release reaction had not taken place 3 min after ADP stimulation. The direct role 15-hydroxyprostaglandin production in ADP-induced aggregation of rabbit platelets is proposed. The involvement of 15-hydroxyprostaglandins in platelet aggregation caused by other inducers is also discussed.
D000244:Adenosine Diphosphate / Q000494:pharmacology*; D000818:Animals; D001095:Arachidonic Acids / Q000494:pharmacology; D003094:Collagen / Q000494:pharmacology; D006911:Hydroxyprostaglandin Dehydrogenases / Q000494:pharmacology*; D007213:Indomethacin / Q000494:pharmacology; D010974:Platelet Aggregation; D011817:Rabbits; D013917:Thrombin / Q000494:pharmacology
D001095:Arachidonic Acids; D000244:Adenosine Diphosphate; D003094:Collagen; D006911:Hydroxyprostaglandin Dehydrogenases; D013917:Thrombin; D007213:Indomethacin