Inhibitory effect of a luteinizing hormone (LH)-releasing hormone agonist on rat ovarian LH and follicle-stimulating hormone receptor levels during pregnancy.
When injected at the daily dose of 100 microgram on days 7 through 12 of pregnancy, the luteinizing hormone (LH)-releasing hormone (LHRH) agonist [D-Ala6, des-Gly-NH2(10)] LHRH ethylamide led to complete suppression of pregnancy and a 45% to 60% decrease in plasma progesterone concentration. The antifertility effect of the LHRH analog was accompanied by an early and almost complete inhibition of ovarian LH/human chorionic gonadotropin and follicle-stimulating hormone receptor levels. These data suggest that the antifertility effects of LHRH agonists are mediated by down-regulation of ovarian gonadotropin receptors and decreased luteal function.
D000818:Animals; D005260:Female; D007987:Gonadotropin-Releasing Hormone / Q000494:pharmacology*; D007986:Luteinizing Hormone / Q000097:blood; D011247:Pregnancy; D011270:Pregnancy, Animal / Q000187:drug effects*; D011374:Progesterone / Q000097:blood; D051381:Rats; D011956:Receptors, Cell Surface / Q000187:drug effects*; D013997:Time Factors
D011956:Receptors, Cell Surface; D007987:Gonadotropin-Releasing Hormone; D011374:Progesterone; D007986:Luteinizing Hormone