title: Androgen deficiency in male rats with prolonged neonatal streptozotocin diabetes.
abstract: We studied the diurnal dynamics of testosterone concentration in male rats with 240-day neonatal streptozotocin-induced diabetes mellitus, which is similar to human type 2 diabetes mellitus. We also studied the effects of intranasal administration of luliberin on testosterone level and the regulation of activities of adenylate cyclase and stimulatory G-proteins in the testicles of diabetic and intact animals by human chorionic gonadotropin. In rats with neonatal diabetes, a decrease in the mean diurnal level of testosterone and its morning rise were observed. The increase in testosterone level 30 min after luliberin administration was significantly reduced in diabetic animals, but no differences in the response to luliberin were observed in intact and diabetic rats 2-6 h after the treatment. The stimulatory effects of human chorionic gonadotropin on adenylate cyclase activity and binding of guanosine triphosphate by stimulatory G-proteins were reduced in the plasma membranes from the testicles of rats with neonatal diabetes in comparison with control specimens. Therefore, rats with neonatal diabetes were characterized by androgen deficiency, which can be related to the impairment of hypothalamic-pituitary-gonadal axis and reduced sensitivity of the adenylate cyclase system in the testicles of diabetic rats to human chorionic gonadotropin.
authors.affiliation: Laboratory for Molecular Endocrinology, I. M. Sechenov Institute of Evolutionary Physiology and Biochemistry, Russian Academy of Sciences, St. Petersburg, Russia. alex_shpakov@list.ru.
authors.forename: K V
authors.initials: KV
authors.lastname: Derkach
authors.forename: I V
authors.initials: IV
authors.lastname: Moyseyuk
authors.forename: O V
authors.initials: OV
authors.lastname: Chistyakova
authors.forename: A O
authors.initials: AO
authors.lastname: Shpakov
mesh_terms: D000262:Adenylyl Cyclases / Q000378:metabolism; D000704:Analysis of Variance; D000818:Animals; D006063:Chorionic Gonadotropin / Q000494:pharmacology; D002940:Circadian Rhythm / Q000502:physiology*; D003921:Diabetes Mellitus, Experimental / Q000097:blood*; D004797:Enzyme-Linked Immunosorbent Assay; D019204:GTP-Binding Proteins / Q000378:metabolism; D007987:Gonadotropin-Releasing Hormone / Q000008:administration & dosage / Q000494:pharmacology*; D006801:Humans; D007030:Hypothalamo-Hypophyseal System / Q000187:drug effects / Q000502:physiology*; D008297:Male; D051381:Rats; D013737:Testis / Q000187:drug effects / Q000502:physiology; D013739:Testosterone / Q000097:blood* / Q000172:deficiency
chemical_list: D006063:Chorionic Gonadotropin; D007987:Gonadotropin-Releasing Hormone; D013739:Testosterone; D019204:GTP-Binding Proteins; D000262:Adenylyl Cyclases