Adrenal function in rats given PMS before puberty: response to ether stress.

Abstract

This study reports the effects of precociously inducedpuberty upon basal serum corticosterone levels and the response to ether stress (ES) in maturing female rats. Precocious puberty was produced by 25 IU pregnant mare’s serum gonadotrophin (PMS) given at 9 a.m. to 26-day-old rats. On days 28 and 30 PMS-treated rats had higher resting values of corticosterone (B) than did saline-treated rats. On day 35, resting B was greatly depressed in PMS-treated rats in comparison to normal controls. On day 28 the response to ES was less sustained in PMS-treated rats whereas at 35 days of age it was very depressed at all time intervals. Ovariectomy at 21 days of age prevented the post-ovulatory depression of basal and stress-evoked serum B after PMS. It is concluded that the onset of puberty stimulates adrenal function and that after ovulation the PMS-stimulated ovary suppresses adrenal function.