Blockage of progesterone-induced release of luteinizing hormone and prolactin by d-amphetamine and fenfluramine in rats.
Subcutaneous administration of d-amphetamine at various doses (1.25, 2.5, and 5 mg/kg) decreased plasma luteinizing-hormone levels in ovariectomized rats primed with estradiol and injected with progesterone. In these animals prolactin levels decreased after injection of 0.6 and 1.25 mg/kg of d-amphetamine. No significant hormone modifications were detected in oavariectomized and ovariectomized estradiol-primed rats after injection of 2.5 mg/kg of d-amphetamine. Fenfluramine at doses of 25 mg/kg induced decreases of plasma LH and prolactin levels in ovariectomized estradiol- and progesterone-treated rats. A low dose of fenfluramine, 2.5 mg/kg, had no effect. It is concluded that d-amphetamine and fenfluramine are able to alter the facilitatory actions of progesterone on luteinizing hormone and prolactin release in ovariectomized estradiol-primed rats.
D000818:Animals; D002369:Castration; D003913:Dextroamphetamine / Q000008:administration & dosage / Q000494:pharmacology*; D004958:Estradiol / Q000008:administration & dosage; D005260:Female; D005277:Fenfluramine / Q000008:administration & dosage / Q000494:pharmacology*; D007986:Luteinizing Hormone / Q000097:blood*; D011374:Progesterone / Q000008:administration & dosage / Q000037:antagonists & inhibitors*; D011388:Prolactin / Q000097:blood*; D051381:Rats
D005277:Fenfluramine; D011374:Progesterone; D004958:Estradiol; D011388:Prolactin; D007986:Luteinizing Hormone; D003913:Dextroamphetamine