Hormonal regulation of testicular LH/hCG receptors in rat.
A single injection of 60 IU of hCG to 25-day-old rats led to a loss of LH/hCG receptors in the testis. The content of [125I] hCG binding sites reached a nadir 2 days after hCG injection. At this time the effect of daily treatment of hormones and other agents on the formation of LH/hCG receptors was studied. Gonadotropin receptors were estimated 2, 4, 6, 8 and 10 days after injection of hCG. Daily treatment of rats with PMSG (30 IU/day) increased testicular content of hCG binding sites. The presence of the pituitary in these animals was necessary during the formation of receptors after hCG-induced loss of binding sites. LH/hCG receptor content remained low in rats treated with testosterone (250 microgram/day), hCG (100 IU/day) or inhibitors of the synthesis and the secretion of prolactininhibitors-bromocryptine (250 microgram/day), ergocryptine (200 microgram/day) and deprenon (50 and 600 micrograms/day). Administration of cortisol (1 mg/day) had no effect on restoration of LH/hCG receptors. These data suggest an important role for FSH and prolactin in the formation of LH/hCG receptors in rat testis.
D000818:Animals; D001971:Bromocriptine / Q000494:pharmacology; D006063:Chorionic Gonadotropin / Q000494:pharmacology; D004873:Ergolines / Q000494:pharmacology; D004958:Estradiol / Q000494:pharmacology; D006064:Gonadotropins, Equine / Q000494:pharmacology; D006728:Hormones / Q000494:pharmacology*; D008297:Male; D051381:Rats; D011919:Rats, Inbred Strains; D011956:Receptors, Cell Surface / Q000378:metabolism*; D011974:Receptors, LH; D013737:Testis / Q000378:metabolism*; D013739:Testosterone / Q000494:pharmacology
D006063:Chorionic Gonadotropin; D004873:Ergolines; D006064:Gonadotropins, Equine; D006728:Hormones; D011956:Receptors, Cell Surface; D011974:Receptors, LH; C004278:D-6-methyl-8-ergolin-1-ylacetic acid amide tartrate; D001971:Bromocriptine; D013739:Testosterone; D004958:Estradiol; C100269:ergocryptine