THE EFFECTS OF NUCLEIC ACIDS ON PITUITARY ACTH CONTENT1

Abstract

RNA, obtained by the phenol extraction method, from rat and beef anterior pituitary glands was administered to rats in order to ascertain the ability of the nucleic acid to increase the tissue content of ACTH. Nucleic acids isolated from rat liver and commercially prepared from beef pancreas were also tested for such activity. The pituitary nucleic acids per se contained no adrenocorticotrophic activity as measured by the adrenal ascorbic acid depletion method. The several RNA preparations were then administered to intact rats, whose pituitaries were then assayed for ACTH content and compared to saline-injected controls. Only the RNA preparations isolated from pituitary tissue were capable of producing increased amounts of ACTH in the glands of recipient rats. The glands of pituitary RNA-treated rats contained nearly twice as much ACTH as controls, based on the adrenal ascorbic acid depletion produced by a given amount of tissue. The pituitaries of rats treated with liver RNA and commercial RNA contained no more ACTH than that found in control glands. The response of increased ACTH tissue levels to pituitary RNA may be due to accelerated protein synthesis, inhibition of ACTH release, or both.