Clomiphene citrate augments follicle-stimulating hormone-induced luteinizing hormone receptor content in cultured rat granulosa cells.
Although clomiphene citrate (CC) has been widely used for ovulation induction, the mechanism of its pro-fertility effect is not entirely clear. Because CC augments ovarian aromatase activity, the effect of CC on follicle-stimulating hormone (FSH)-induced luteinizing hormone (LH) receptor content was examined in primary cultures of rat granulosa cells. Control cultures contained low LH receptor content, whereas FSH stimulated LH receptor formation in a dose-dependent manner. The concomitant addition of CC enhanced FSH potency as shown by a decrease in the ED50 for FSH by 2.2-fold. Some cells were treated with a low concentration of FSH (12 ng/ml) in the presence or absence of increasing concentrations of CC (10(-8) M to 10(-6) M). The enhancement of FSH-stimulated LH receptor formation was found to be CC dose dependent, with an ED50 of 6 X 10(-8) M. Thus, CC may play a direct ovarian role in the enhancement of FSH-stimulated LH receptors. The gonadal action of this compound may be relevant in understanding the efficacy of CC in ovulation induction.
D000818:Animals; D002478:Cells, Cultured; D006063:Chorionic Gonadotropin / Q000378:metabolism; D002996:Clomiphene / Q000494:pharmacology*; D000242:Cyclic AMP / Q000032:analysis; D004305:Dose-Response Relationship, Drug; D004357:Drug Synergism; D005260:Female; D005640:Follicle Stimulating Hormone / Q000494:pharmacology*; D006107:Granulosa Cells / Q000187:drug effects* / Q000378:metabolism; D051381:Rats; D011919:Rats, Inbred Strains; D011974:Receptors, LH / Q000032:analysis / Q000187:drug effects* / Q000378:metabolism; D013268:Stimulation, Chemical
D006063:Chorionic Gonadotropin; D011974:Receptors, LH; D002996:Clomiphene; D005640:Follicle Stimulating Hormone; D000242:Cyclic AMP