P-94: The Effect of Superovulation on Oviduct and Ovary Structure of NMRI Mice

Background: To determine the effect of ovarian stimulation on the height of the epithelial cells of fallopian tubes and development of ovarian follicles and corpus luteum in NMRI mice. Materials and Methods: Forty female NMRI mice of 6 to 8 weeks were selected and divided into 4 groups: control group, 10 mice that were injected with saline. The second group of 10 mice that were injected with 7 uI PMSG. The third group 10 mice that were injected with 10 UI PMSG. Fourth group of 10 mice that were injected with 12 UI PMSG. 48 hours after injection of PMSG, HCG was injected intraperitoneally. 24 hours after the injection of HCG, the mice were killed by cervical dislocation and their ovaries removed and studied by light microscopy, were stained with H & E. And the height of the epithelial cells of the fallopian tube, ovary size, number and size of follicles and corpus luteum in the four groups were compared. Results: In group 2 (injected with 7 UI) there was no significant change in the number of follicles, size and number of the corpus luteum and ovary size compare with control group. Also there was no significant change in size multilayer primary (preantral) and secondary (antral) follicles compared with control group. But the size of the graafian follicle increased than the control group. The size of unilayer primary follicles was significantly lower than the control group. In group 3 (injected with 10 uI) number of multilayer primary follicles (preantral) was increased compared to control. But number of other follicles, ovarian size and graafian follicle size was no significant change. Increased number and decreased size of corpus luteum compared with group 2 and control. Decreased size of unilayer follicle compared with group 2. Increased size of secondry follicles compared with group 2 and control. In group 4 (injected with 12 uI) ovarian size significantly increased as compared to groups 1 and 3. Increased number of the corpus luteum compared with group 2 and control.Increased multilayer primary (preantral) and graaphian follicles compared to other groups. The size of the unilayer primary follicle was significantly decreased compared to control. Secondary follicle size was significantly increased compared with group 2. Graafian follicle size was significantly decreased compared to group 2. Conclusion: The findings of this study indicate that PMSG and hCG hormone even with increased dose has no effect on the number of unilayer primary follicles, but their size is reduced. But the basic multi-layered follicles (preantral), increasing the gonadotropin dose, increase their number, but they have no influence on their size. Increased gonadotropin dose increased Secondary or antral follicles size but has no effect on their numbers. Increase the number of Graaphian follicles, occurs only in high doses but reduces the size of the Graaphian follicle while low dose increasing the size of the Graaphian follicle. High doses may cause negative effects on the follicle size, that needs to be more investigated. The study also showed that increasing the dose of hormones, reduces the size and increasing the number of the corpus luteum . Ovarian size is increased only in the high dose and low dose did not affect the size of the ovary. Another result of this study is reducing the height of the oviductal epithelium with PMSG and hCG hormone stimulates ovulation and if the hormone level increase, the height of the epithelium reduced.