Steroid induction of gonadotropin surges in the immature rat. II. Triggering ability of progesterone metabolites, adrenocortical hormones, and adrenocorticotropin.
Several adrenocortical steroids were tested for their ability to trigger LH release in estrogen-primed sexually immature female rats. Massive LH surges, approaching these known to be triggered by progesterone (P), followed the injection of depot ACTH1-24 and also of the adrenal steroids deoxycorticosterone (DOC) and 4-pregnen-21-ol-3,20-dione 21-acetate, but not of 5 alpha- and 5 beta-pregnan-21-of-3,20-dione, corticosterone, or aldosterone. Estrogen-primed adrenalectomized/ovariectomized rats also responded to DOC, albeit to a lesser extent. The P metabolites 5 alpha-pregnana-3,20-dione, 4-pregnen-20 alpha-ol-3-one, and 3 alpha-hydroxy-5 alpha-pregnan-20-one proved ineffective, although their triggering ability in adults was confirmed. It is concluded that adrenal P and DOC are potent activators of the gonadotropin surge system underlying pubertal ovulation and that P metabolites may acquire biological properties during sexual maturation.
D000305:Adrenal Cortex Hormones / Q000494:pharmacology*; D000324:Adrenocorticotropic Hormone / Q000494:pharmacology*; D000818:Animals; D002369:Castration; D003900:Desoxycorticosterone / Q000494:pharmacology; D004958:Estradiol / Q000494:pharmacology; D005260:Female; D007986:Luteinizing Hormone / Q000097:blood*; D011374:Progesterone / Q000378:metabolism / Q000494:pharmacology*; D051381:Rats
D000305:Adrenal Cortex Hormones; D003900:Desoxycorticosterone; D011374:Progesterone; D004958:Estradiol; D000324:Adrenocorticotropic Hormone; D007986:Luteinizing Hormone