Induction of Sexual Maturation in Female Eels Anguilla japonic a by Recombinant Eel Gonadotropin Produced in Silkworm

摘要

This study investigated the effects of recombinant eel gonadotropin hormone (rJeGTH) produced in silkworms, with and without a carboxyl-terminal peptide from equine chorionic gonadotropin (eCG), on the induction of sexual maturation in female eels Anguilla japonica. Experiments were conducted both in vivo and in vitro. In in vitro trials, germinal vesicle breakdown (GVBD) induction did not significantly differ between rJeFSH and rJeFSH-eCG treatments and the control group. However, previous studies did find that rJeLH and rJeLHeCG treatments induced GVBD in female eels. Our in vitro exploration of estradiol-170 (E2) levels in immature ovarian tissues revealed significantly higher E2 levels in the group treated with rJeFSH-eCG 1 ug/mL than in the control group. In contrast, the in vivo experiments showed no effect of recombinant hormones on the sexual maturation of feminized eels. Previous studies and our own in vitro results have clearly shown that rJeGTH and rJeGTHeCG have a positive effect on thesexual maturation of feminized eels. To develop the activity of rJeGTH in vivo, further studies should confirm circulation time and activity of these hormones in eels' bloodstream, modify the structure of the recombinant gene, and implement additional glycosylation.