the evidence that hypothalamic gonadotropin-releasing hormone ( gnrh ) release increases during the estrogen-induced luteinizing hormone ( lh ) surge in castrated female macaques and that estrogen induces a similar lh surge in the male suggests that either sexual differentiation of gnrh secretion does not exist or that changes in brain gnrh are not critical for ovulation .
C0020663
hypothalamic
C0023610
gnrh