Thromboxane B2 synthesis in human platelets induced by the late complement components C5b-9.
Sublytic doses of purified C5b6, C7, C8 and C9 induce the release of thromboxane B2 (TXB2) in human platelets. In the present study, we attempted to analyze the signal by which C5b-9 triggers the prostanoid synthesis in platelets. TXB2 release was accompanied by liberation of Ca++ from intracellular stores. Influx of Ca++ was not observed, indicating that C5b-9 did not form a channel large enough to permit passage of Ca++ ions. Therefore, channel formation is apparently not required for cell stimulation.
D016718:Arachidonic Acid; D001095:Arachidonic Acids / Q000378:metabolism; D001792:Blood Platelets / Q000187:drug effects* / Q000378:metabolism; D002118:Calcium / Q000378:metabolism; D015938:Complement Membrane Attack Complex; D003165:Complement System Proteins / Q000494:pharmacology*; D006801:Humans; D007424:Intracellular Fluid / Q000378:metabolism; D007473:Ion Channels / Q000378:metabolism; D010743:Phospholipids / Q000378:metabolism; D013268:Stimulation, Chemical; D013929:Thromboxane B2 / Q000096:biosynthesis* / Q000378:metabolism
D001095:Arachidonic Acids; D015938:Complement Membrane Attack Complex; D007473:Ion Channels; D010743:Phospholipids; D016718:Arachidonic Acid; D013929:Thromboxane B2; D003165:Complement System Proteins; D002118:Calcium