[Immediate and late effects of 17-beta-estradiol on prolactin in the mangabey]

Thirty seven mature Mangabeys (Cercocebus atys lunulatus), 33 females (5-6 kg) and 4 males (6-7 kg) received large doses of 17-beta-oestradiol by intravenous tracts (continued perfusion and single dose injection) and by subcutaneous implantation in a silastic tube. The CB 154 and TRH tests under oestrogenic treatment were the object of an integrated study. All these experiments began 5 days after menstruation in the case of the females. The experiments were preceded, for each monkey, by a control period that rarely exceeded 5 days. Prolactin and oestradiol were measured by radioimmunoassay. Single intravenous injection and perfusion of 17-beta-oestradiol were followed by an inconstant effect on the immediate secretion of prolactin (+30 to +60 minutes). However, after 4 to 6 hours, serum prolactin rose by about 50% of the basic ratios. This is followed by a more notable elevation of the blood ratios of PRL during the 24 to 72 hours which succeed the end of the oestradiol treatment. The subcutaneous placing of a silastic tube containing oestradiol is followed by a Systematic fall in the Serum PRL for 9 hours (day 0). During the following 3 weeks, the ratios rise but are situated at a normal level (F = 0.2 p greater than 0.5) in spite of a liberation and maintenance of the serum oestrogen at a very high level. Nevertheless, the peak of PRL following a TRH test under oestrogenic treatment is greater (F = 4.7 p less than 0.05) than the peak obtained during the control period with the same dose of TRH.