THE RESPONSE OF THE SEBACEOUS GLANDS OF HYPOPHYSECTOMIZED—CASTRATED MALE RATS TO ADRENOCORTICOTROPHIC HORMONE AND TO TESTOSTERONE

Administration of 1 i.u./24h of adrenocorticotrophic hormone (Cortrophin ZN, ACTH) to hypophysectomized—castrated rats significantly increased sebum production to the level of that in castrated rats with intact pituitaries. The incidence of mitoses in the sebaceous glands was also significantly increased. Neither the preputial glands nor the seminal vesicles showed any response.No significant increase in sebum production in hypophysectomized—castrated rats could be detected 24 days after giving implants releasing 0·2 or 0·6 mg testosterone/24 h, although sebaceous mitoses were significantly increased in both instances. Concomitant administration of both ACTH and testosterone raised sebum production to the same extent as ACTH alone, and raised the incidence of sebaceous mitoses to a level equal to that produced by ACTH plus testosterone.It is concluded that the sebaceous glands respond—either directly or indirectly as the result of stimulation of the adrenal cortex—to ACTH and that this response is less dependent on the presence of the pituitary than is the action of testosterone. ACTH does not itself facilitate the response of the sebaceous glands to testosterone.