Effects of bilateral amygdaloid lesions on gonadal and pituitary hormones in serum and on sexual behavior in female rhesus monkeys

Bilateral lesions that destroyed the amygdaloid nuclear complex failed to alter either serum concentrations of luteinizing hormone (LH), estradiol (E2), progesterone, and testosterone or sexual behavior in female rhesus monkeys. In 3 of 5 females ovulation occurred in the postoperative cycle, and in 4 of 5 females exogenous E2 treatment released a surge of LH whose pattern was indistinguishable from the normal preovulatory surge. A postcastration rise in serum LH also occurred in the 5 lesioned monkeys, and E2 again induced an LH release. The data suggest that the amygdala does not play a major role in regulation of LH or ovarian steroid secretion during the menstrual cycle. Moreover amygdaloid lesions in female monkeys do not alter their sexual behavior.