Observations on Role of Free Sulfhydryl Groups in Prothrombin Activation.

Abstract

Incubation of human plasma or purified bovine prothrombin with either reduced or oxidized glutathione prior to initiation of prothrombin activation results in inhibition of thrombin formation,the same degree of inhibition being observed with considerably lower concentrations of GSSG than of GSH. Whereas the effect of GSH is, at least partially, due to its formation of GSSG the latter appears to react with at least one prothrombin conversion accelerator. Other SH-oxidizing and-blocking agents react similarly indicating the essential nature of free sulfhydryl groups on such an accelerator and establishing their importance in the blood clotting mechanism. Possible implications of these findings are discussed.