Abstract
The pubertal increase in gonadotropins in the female rabbit was inhibited 14–42-fold with Silastic implants of progesterone (P4) testosterone propionate (TP), estradiol benzoate (EB) or P4/EB placed subcutaneously on Day 24 of life. Rabbits with empty implants showed the normal prepubertal increase in circulating gonadotropins. By contrast, rabbits with implants of P4 only, had a 2-fold decrease in LH secretion when peak areas were compared. However, FSH secretion though slightly depressed was not significantly different from controls. The prepubertal increase in circulating gonadotropins was completely suppressed by implants of EB, TP and combined P4/EB. At 115-days-of-age, sexual receptivity and mating were absent in EB-treated animals and significantly suppressed in P4-treated ones when compared to controls, all of which mated. Mating was not completely inhibited in TP and combined P4/EB animals. Corpora lutea were found in all rabbits that mated. In the sexually non-receptive does, vaginal stimulation induced an LH surge in 2 of 15 animals. Ovarian weights and follicular development were significantly suppressed in rabbits with EB implants. Ovarian estradiol content was significantly increased in P4- and TP-treated rabbits. Maximum specific binding for [ 3H]naloxone was suppressed in the hypothalami of P4-treated rabbits. These results suggest that the prepubertal increase in circulating gonadotropins may have an essential role in the control of sexual maturation in the female rabbit.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
