In vitro effects of arginine vasotocin on testosterone production by testes of rainbow trout (Oncorhynchus mykiss).
The objective of this study was to investigate the effect of arginine vasotocin (AVT) on testosterone (T2) production by the rainbow trout testis in culture. AVT increased T2 production in a dose-dependent manner in immature testes. The maximum response (10 nM AVT) increased T2 production 6-fold over basal (3-6 pg/mg tissue protein). Mature testes did not respond to AVT. Salmon gonadotropin (2.5 nM sGtH, SGA-GtH) stimulated T2 production by both juvenile (5-fold) and mature (11-fold) testes. When AVT (100 nM) was added in addition to salmon gonadotropin (sGtH; from 0.1 to 100 nM), AVT had a stimulatory effect at the submaximal doses of sGtH, but T2 production did not exceed the maximum level obtained with sGtH (100 nM) alone. Isotocin also increased T2 production although to a lesser degree than AVT. The maximum response at 10 nM increased T2 production 4-fold over basal. beta-Endorphin had no effect on T2 production.
Rodríguez
M
M
Department of Zoology, University of Rhode Island, Kingston 02881.
Specker
J L
JL
D000818:Animals; D002478:Cells, Cultured; D004305:Dose-Response Relationship, Drug; D006062:Gonadotropins / Q000494:pharmacology; D008297:Male; D011863:Radioimmunoassay; D012474:Salmon; D012741:Sexual Maturation; D013737:Testis / Q000187:drug effects / Q000254:growth & development / Q000502:physiology*; D013739:Testosterone / Q000096:biosynthesis* / Q000378:metabolism; D014337:Trout; D014668:Vasotocin / Q000494:pharmacology*; D001615:beta-Endorphin / Q000494:pharmacology
D006062:Gonadotropins; D013739:Testosterone; D001615:beta-Endorphin; D014668:Vasotocin