Yoshinori Taketomi

Metabolic and kinetic study of thrombogenesis: regulatory mechanism in early step of platelet plug formation.

Abstract Metabolic and kinetic study of platelets to predict thrombogenic episodes were conducted on the subjects who had remarkable thrombocytosis and who had been subjected artificial heart valve replacement and put under antiplatelet therapy. Initial step of platelet plug formation are closely energy dependent. Epinephrine-induced aggregation of platelets in CML with thrombocythemia are impaired as well as metabolic response via citric acid cycle. This refractory response are also observed in the platelet under the antiplatelet therapy: dipyridamole, aspirin. Partial correction of those abnormalities by addition of PGE2 (F2α) suggested their participation in regulatory mechanism of aggregability and/or release mechanism. To evaluate clinical effects of these metabolic suppressive agents in vivo, kinetic study was done on those patients. Thrombocytosis above one million itself did not promote platelets consumption, however, implantation of artificial surface brought about mild increase of consumption resulting in mild thrombocytopenia. This kinetic study is proved to be promising to predict thrombogenic episodes and their prognosis.