Transitory Increases of Luteinizing Hormone and Follicle-Stimulating Hormone Following Luteectomy in Hemiovariectomized Primates Significantly Increase Progesterone Secretion In Vitro by the Subsequent Corpus Luteum1

Ten chronically hemiovariectomized cynomolgus and rhesus monkeys were luteectomized 5.5 ± 0.3 days after the midcycle luteinizing hormone (LU) and follicle-stimulating hormone (FSH) surge in two consecutive cycles. The corpus luteum (CL) was removed, weighed, dispersed with colla-genase and the luteal cells counted. Luteal cells (50,000/mI) were incubated in Ham’s FlO medium for 3 h at 37#{176}Ceither in the presence or absence of 100 ng/ml human chorionic gonadotropin (hCG). Daily blood samples were taken from the monkeys throughout the study for determination of LH, FSH, estradiol (E2) and progesterone levels. Within 5 days following each luteectomy (LX), all monkeys responded with a significant increase in FSH and LH (P<0.05). Ovulatory LH/FSH surges occurred 14.4 ± 0.5 days after the first LX. Hormonal profiles of serum progesterone prior to the first and second LX, CL weight and number of luteal cells/CL were similar (P>0.05). How-ever, luteal cells obtained at the second LX produced more progesterone (P<0.05) in vitro under basal and hCG-stimulated conditions than cells from the first LX. The areas under the LH and FSH curves following the first LX were highly correlated (P<0.05) with the in vitro progesterone production following the second LX. Thus, the monkeys with the largest areas under the LH and FSH curves subsequently had the highest in vitro progesterone production