title: Effect of melatonin and 5-methoxytryptamine on sex steroids and thyroid hormones during the prespawning phase of the annual reproductive cycle in the freshwater teleost, Clarias batrachus.
abstract: Melatonin and 5-methoxytryptamine have been studied in the freshwater teleost Clarias batrachus during the prespawning period. The data have provided evidence of the inhibitory effects on sex steroids and thyroid hormones when the pineal indoleamines melatonin and 5-methoxytryptamine (5-MT) are administered intramuscularly daily in the afternoon for 27 days. The different dose levels had different effects. The higher dose levels of melatonin showed the initiation of counter inhibitory impacts on testosterone and T3, T4 levels. The melatonin acted more effectively than 5-MT.
mesh_terms: D019326:17-alpha-Hydroxyprogesterone; D008735:5-Methoxytryptamine / Q000494:pharmacology*; D000818:Animals; D002397:Catfishes / Q000097:blood*; D004958:Estradiol / Q000097:blood; D004970:Estrone / Q000097:blood; D005260:Female; D012739:Gonadal Steroid Hormones / Q000097:blood*; D006908:Hydroxyprogesterones / Q000097:blood; D008297:Male; D008550:Melatonin / Q000494:pharmacology*; D011863:Radioimmunoassay; D012098:Reproduction / Q000187:drug effects*; D013739:Testosterone / Q000097:blood; D013963:Thyroid Hormones / Q000097:blood*; D013974:Thyroxine / Q000097:blood; D014284:Triiodothyronine / Q000097:blood; D014363:Tryptamines / Q000494:pharmacology*
chemical_list: D012739:Gonadal Steroid Hormones; D006908:Hydroxyprogesterones; D013963:Thyroid Hormones; D014363:Tryptamines; D014284:Triiodothyronine; D004970:Estrone; D008735:5-Methoxytryptamine; D013739:Testosterone; D004958:Estradiol; D019326:17-alpha-Hydroxyprogesterone; D008550:Melatonin; D013974:Thyroxine