Treatment of GnRHa-implanted Senegalese sole (Solea senegalensis) with 11-ketoandrostenedione stimulates spermatogenesis and increases sperm motility.
The effect of 11-ketoandrostenedione (OA) on plasma concentrations of sexual steroids and spermatogenesis of Senegalese sole (Solea senegalensis) implanted with gonadotropin-releasing hormone agonist (GnRHa) was investigated. Males were treated with saline (control) or with GnRHa implants (50 mug kg(-1)) in the presence or absence of OA (2 or 7 mg kg(-1)) during twenty eight days. Treatment with GnRHa alone slightly stimulated spermatogenesis and milt production with respect to controls, and this was associated with a transient elevation of plasma 11-ketotestosterone (11-KT) at day seven and an increase of 5beta-reduced metabolite(s) of 17,20beta-dihydroxy-pregn-4-en-3-one (17,20betaP) at day twenty eight. However, treatment with GnRHa+OA increased plasma concentrations of 11-KT and free+sulphated 5beta-reduced metabolites of 17,20betaP at days seven, fourteen and twenty one. After twenty eight days, the testis of GnRHa+OA-treated fish showed a lower number of spermatogonia B and spermatocytes I, and a higher number of spermatids, than fish treated with GnRHa alone. In addition, the motility of spermatozoa produced by GnRHa+OA males was enhanced by 2-fold with respect to controls or GnRHa males. These results suggest that treatment of Senegalese sole with GnRHa+OA stimulates spermatogenesis resulting in more motile sperm. Such effects could be mediated by an increased synthesis of 11-KT and/or 17,20betaP in the testis but further studies will be required to elucidate the specific mechanism involved.
Agulleiro
Maria J
MJ
IRTA Center of Aquaculture, 43540-Sant Carles de la Ràpita, Tarragona, Spain.
Scott
Alexander P
AP
Duncan
Neil
N
Mylonas
Constantinos C
CC
Cerdà
Joan
J
D000736:Androstenes / Q000494:pharmacology*; D000818:Animals; D005412:Flatfishes / Q000502:physiology*; D007987:Gonadotropin-Releasing Hormone / Q000031:analogs & derivatives* / Q000494:pharmacology; D006908:Hydroxyprogesterones / Q000097:blood; D020007:Implants, Experimental; D008297:Male; D012965:Sodium Chloride / Q000494:pharmacology; D013081:Sperm Motility / Q000187:drug effects*; D013091:Spermatogenesis / Q000187:drug effects*; D013094:Spermatozoa / Q000166:cytology / Q000187:drug effects; D013737:Testis / Q000187:drug effects; D013739:Testosterone / Q000031:analogs & derivatives / Q000097:blood
D000736:Androstenes; D006908:Hydroxyprogesterones; C007433:17,20-dihydroxy-4-pregnen-3-one; D007987:Gonadotropin-Releasing Hormone; D013739:Testosterone; D012965:Sodium Chloride; C083781:LHRH, Ala(6)-Gly(10)-ethylamide-; C011657:adrenosterone; C003600:11-ketotestosterone