The ovulatory surge of gonadotropin and sexual receptivity in the female golden hamster

The present experiments were undertaken to study the nature of the relationship between ovulatory gonadotropin (GTH) release and subsequent sexual behavior in the hamster. GTH antiserum (GTH A/S) injected just prior to the release of the GTH surge prevented both ovulation and lordotic behavior. Both behavior and ovulation could be restored by injecting LH. FSH was effective in restoring ovulation but appeared to have less effect on behavior as compared to LH. Progesterone restored behavior but not ovulation. Large doses of estradiol had no effect on either parameter. The results suggest that ovulatory GTH release (especially LH) is a central event leading to the onset of a sexual receptivity. GTH probably acts by stimulating ovarian progesterone. This steroid acts to induce receptivity and also appears to induce a subsequent period during which the female is behaviorally refractory to sex steroids.