title: Alterations in steroidogenesis and human chorionic gonadotropin binding in the cryptorchid rat testis.
abstract: One month after the induction of cryptorchidism in adult rats, serum levels of LH and FSH were significantly elevated in comparison with sham-operated controls, whereas serum levels of testosterone remained low to normal. Testis weight in cryptorchid rats was reduced by over 66%, and once the extratubular fluid was removed by decapsulation, the reduction in weight was 78%. The basal production of testosterone, pregnenolone, and estradiol in vitro by testes from cryptorchid rats was similar to controls, whereas significantly less androstenedione was produced. Testicular stimulation in vitro with a high dose of hCG (360 pM) resulted in significantly greater production of testosterone, pregnenolone, and estradiol by cryptorchid than by control rat tissue. The in vitro binding of [125I]hCG per testis was decreased in the cryptorchid state to 40% of control values, probably as a result of down-regulation of LH receptors due to the 4-fold elevation of serum LH levels in the cryptorchid rats.
mesh_terms: D000728:Androgens / Q000096:biosynthesis*; D000735:Androstenedione / Q000096:biosynthesis; D000818:Animals; D006063:Chorionic Gonadotropin / Q000378:metabolism* / Q000494:pharmacology; D003456:Cryptorchidism / Q000378:metabolism*; D004958:Estradiol / Q000096:biosynthesis*; D005640:Follicle Stimulating Hormone / Q000097:blood; D007986:Luteinizing Hormone / Q000097:blood; D008297:Male; D009929:Organ Size; D011284:Pregnenolone / Q000096:biosynthesis*; D051381:Rats; D013737:Testis / Q000378:metabolism*; D013739:Testosterone / Q000096:biosynthesis
chemical_list: D000728:Androgens; D006063:Chorionic Gonadotropin; D013739:Testosterone; D000735:Androstenedione; D004958:Estradiol; D011284:Pregnenolone; D007986:Luteinizing Hormone; D005640:Follicle Stimulating Hormone