Preferential utilization of endogenous arachidonate by cyclo‐oxygenase in incubations of human platelets

[摘要]

Thromboxane B₂ (TXB₂) and 12-hydroxy-5,8,10,14-eicosatetraenoic acid (12-HETE) formed from the endogenous and exogenous arachidonate during human platelet incubation, was evaluated by selected ion monitoring (SIM). TXB₂ formed from endogenous substrate accounted for about one third of the total, whereas the great part of 12-HETE derived from exogenous arachidonate. These data indicate that under the tested conditions the pool of arachidonate that acts as substrate for cyclo-oxygenase is different from the pool that acts as substrate for lipoxygenase and that the arachidonate released from phospholipids is preferentially utilized by cyclo-oxygenase.

[学科分类] 生物化学/生物物理

[关键词] TXB2;12-HETE;Arachidonic acid;Cyclo-oxygenase;Lipoxygenase;Human platelets;TXA2;thromboxane A2;TXB2;thromboxane B2;12-HETE;12-hydroxy-5;8;10;14-eicosatetraenoic acid;12-HPETE;12-hydroperoxy-5;8;10;14-eicosatetraenoic acid;HHT;12-hydroxy-5;8;10-heptadecatrienoic;PGs;prostaglandins;PRP;platelet-rich plasma;SIM;selected ion monitoring;RIA;radioimmunoassay;TLC;thin-layer chromatography;RGLC;radiogaschromatography;BSTFA;N;O-bis-(trimethylsilyl)-trifluoroacetamide