Corticosteroids and incorporation of C14-phenylalanine into protein of isolated rat diaphragm

Abstract

Prior treatment of rats with cortisone (2 mg/day) decreased l-phenylalanine-U-C14 incorporation into protein of isolated diaphragm. This action was not affected by a 100-fold change in the phenylalanine concentration, indicating that the steroid depresses protein biosynthesis in muscle. Hydrocortisone (50 µg/ml) added in vitro did not alter C14-phenylalanine incorporation. Large changes in intracellular potassium concentration were without influence on phenylalanine incorporation into protein of diaphragms from normal, adrenalectomized or cortisone-treated rats.