Abstract
An injection of ACTH caused a remarkable stimulation in the rate of. 3H-choline incorporation into ethanol-ether extractable fraction of the subcellular components from rat adrenal glands as early as 3.5hr after the injection. The rate of increase in the incorporation due to ACTH administration was most conspicuous in the inner membrane fraction of mitochondria; in this fraction almost 500% increase was observed. Administration of cycloheximide in amount that blocks protein synthesis prior to ACTH treatment inhibited the ACTH effect on the choline incorporation completely, while a large dose of Actinomycin D did not show any influence on the ACTH action.
