Regulation of platelet aggregation and arachidonate metabolism in streptozotocin-diabetic rats.
Thromboxane A2 generation during collagen-induced platelet aggregation was increased in platelets from streptozotocin-induced diabetic rats when washed platelets were resuspended in pooled-control rat plasma. 14C-Arachidonate incorporation into platelets and oxygenation into thromboxane B2 in these rats were significantly higher than in the control rats, whereas fatty acid analysis revealed markedly decreased arachidonate composition in platelet phospholipids. Meanwhile plasma isolated from diabetic rats inhibited collagen-induced platelet aggregation in a volume-dependent fashion. These results suggest that enhanced platelet thromboxane synthesis in streptozotocin-diabetic rats is accompanied by increased arachidonate metabolism in platelets, which may serve to aid efficient utilization of a decreased thromboxane A2 precursor pool. Plasma factor(s) in these rats may modify the platelet reactivity in vivo.
D000818:Animals; D016718:Arachidonic Acid; D001095:Arachidonic Acids / Q000378:metabolism*; D001792:Blood Platelets / Q000378:metabolism; D003094:Collagen / Q000494:pharmacology; D003921:Diabetes Mellitus, Experimental / Q000097:blood*; D005227:Fatty Acids / Q000097:blood; D008297:Male; D010743:Phospholipids / Q000097:blood; D010974:Platelet Aggregation / Q000187:drug effects; D051381:Rats; D011919:Rats, Inbred Strains; D013311:Streptozocin; D013928:Thromboxane A2 / Q000378:metabolism; D013929:Thromboxane B2 / Q000378:metabolism
D001095:Arachidonic Acids; D005227:Fatty Acids; D010743:Phospholipids; D016718:Arachidonic Acid; D013929:Thromboxane B2; D013928:Thromboxane A2; D013311:Streptozocin; D003094:Collagen