THE INFLUENCE OF THE PITUITARY ON THE RESPONSE OF THE SEBACEOUS AND PREPUTIAL GLANDS OF THE RAT TO PROGESTERONE

Progesterone, given as an implant releasing 0·1–0·2 mg./day for 24 days, failed to increase sebum production or preputial gland weight in castrated or hypophysectomized-castrated male rats. A dose of 10 mg./day in arachis oil also failed to increase sebum production or mitoses in the sebaceous glands, though it increased by 70% preputial gland weight in the presence of the pituitary.Hypophysectomy greatly reduced preputial gland wt, and the response of hypophysectomized rats to 10mg. progesterone/day was much less than when the pituitary was present. A porcine growth hormone preparation, known to facilitate the response of the sebaceous gland to testosterone in the hypophysectomized rat, failed to facilitate the response of the preputial gland to progesterone.It is concluded that 'sebum-permissive' activity (the facilitation of the response of the sebaceous gland to testosterone) may be distinct from ' sebotropic' activity (facilitation of the response of the preputial gland to progesterone), and it is argued that each of these activities may prove to be separable from somatotrophic activity.