Metabolism of L-thyroxine by phagocytosing peritoneal macrophages.

Abstract

Induction of phagocytosis in peritoneal macrophages resulted in a great stimulation of the deiodination of 125I-labeled L-thyroxine ([125I] T4). Despite the stimulation of deiodination, the quantity of undegraded [125I] T4 in the cells was increased, suggesting that increased cellular uptake is a factor contributing to the stimulation of deiodination that phagocytosis induces. The increased deiodination of T4 by phagocytosing cells could contribute to the acceleration of T4 metabolism that occurs during acute bacterial sepsis in vivo. (Endocrinology 94: 920, 1974)