LH-RH-Induced Gonadotropin Release in Chimpanzees

The ability of LU-RH (125 µg iv) to induce LH and FSH release was studied in 5 male and 11 female adult chimpanzees. LH peaks were found after LH-RH treatment in all the chimpanzees studied. Both LH and FSH peak responses were greater when the releasing hormone was given to periovulatory (LH 560, FSH 210 percent of control) rather than follicular (LH 290, FSH 190 percent of control) or luteal (LH 370, FSH 140 percent of control) phase females, or males (LH 280, FSH 120 percent of control). In contrast female rhesus monkeys were relatively insensitive when LH-RH was given (10, 20, 40 or 80 µg) during the follicular phase of the menstrual cycle (LH 115 percent control). These data support the findings of others that rhesus monkeys do not uniformly respond to LH-RH and further suggest an alternative nonhuman primate species for releasing hormone studies.