A Mechanism of Action for Antithyroid Activity of Reserpine.

Abstract

Summary 1) Endogenous dehydrogenase enzyme activity of the thyroid was quantitated employing the tetrazolium technic. Reserpine and thyroxin significantly lowered enzyme activity, whereas thyrotropin and thiouracil significantly raised it. Thyrotropin, either exogenous or endogenous in origin, prevented reduction of enzyme activity achieved by administration of reserpine alone. 2) The suggestion that these effects are a reflection of thyrotropin activity upon the thyroid is discussed. It is proposed that reserpine does have an antithyroid action and that this action is the result of its effect upon the elaboration or release of thyrotropin by the pituitary.