[Effect of glucocorticoid hormones on nuclear RNA-polymerase activity and RNA metabolizability in rat skeletal muscles].

It has been found that in hypercorticism induced by a prolonged ACTH administration when protein synthesis is inhibited in the skeletal muscles the incorporation of Na2HP32O4 into muscle RNA intensifies by 30% and the RNA-polymerase activity of muscle nuclei is approximately twice as high. In the adrenalectomized rats 3 hours after a single hydrocortisone administration a sharp rise in the RNA-polymerase activity of the skeletal muscle nuclei is observed as well. Such an increase in RNA synthesis is suggested to be a response to the inhibition of protein synthesis through feedback mechanisms.