The Expression Of Growth Differentiation Factor-9 And Cyclooxygenase-1 In Polycystic Ovary Syndrome And Normal Rats

Objective: In our country Polycystic ovary syndrome (PCOS) with a huge crowd is a gynecological endocrine disease. In this study we used PCOS rat model to observe the expression of growth differentiation factor-9 (GDF-9) and cyclooxygenase-1 (COX-1) which is the rate-limiting enzyme in Prostaglandin E2 synthesis, study the rule of their expression in the follicular development, approach their function in the ovarian local regulation in the ovaries of PCOS rats and normal rats and the reasons for the stagnated follicular development and the disruption of follicular advantaging choice in PCOS .Materials and Methods: 55 about 85 days-old female Sprague Dawley (SD) rats were randomly divided into two groups: 35 in group A as PCOS group using Poretsky's method; 20 in Group B as control group. After the 22 day-injections, all the rats abrosiaed. The next day they were anesthetized, then sampled blood. We collected serum samples from the blood after 20min 3000r/min centrifugalizatio,and then stored them at -20℃,for detecting the contents of serum testosterone (T), luteinizing hormone (LH) and insulin (FINS). The bilateral ovaries were dislodged, weighed, and ripped through the major axis. The right ovaries were fixed in 4% neutral formalin for 24h, as the materials for detecting the expression of GDF-9 and COX-1 by immunohistochemistry. Another ones storing at -80℃were used for the detection GDF-9 by flow cytometry (FCM).Statistical analysis: Data of RIA demonstrated with x±s, and t-test was used for analysesing the differences between the groups; the results of immunohistochemistry were analysesed withχ2 test. All data were analyzed by SPSS11.5 statistical software. p<0.05 demonstrates significantly disparation.Results:1 Rats weight: The weight of the rats in PCOS group is heavier than that in control group (p<0.01).2 Ovarian morphology of Gross Anatomy: In PCOS group we can see that the ovarian volume is significantly increased , the ovarian surface is pale and a number of cystic follicles were visible with less corepus luteum. In control group we can see the ovarian surface is rosy and the corepus luteum conspicuously increased than that in PCOS group. The ovarian weight in PCOS group increased significantly than that in control group (p<0.01).3 Ovarian tissue examination: In the PCOS group we can see more primordial follicles and abnormal follicles (including atretic follicles), cystic follicles increased significantly, granulosa cell layers decreased to 2 to 3 layers, oocyte- corona- cumulus complex disappeared, the number of corepus luteum decreased significantly with incompletly luteinization. In the control group we can see a number of corepus luteum, the follicles in different developmental phase, the follicular granulosa cells are in a multi-layer, multi 8 ~ 9.4 Serum levels of sex hormones comparison: The levels of T, LH, FINS increased significantly in PCOS group.5 The expression of GDF-9 in PCOS ovary: Immunohistoc- hemical results show that: In PCOS group GDF-9 is expressed in the cytoplasm of oocytes of the primary follicles, secondary follicles and sinusoid follicles, and it's also expressed in the granulosa cells and thecal cells. These are similar with the control group. In the PCOS group GDF-9 isn't expressed in the cytoplasm of oocytes of the primordial follicles, but in control group GDF-9 is expressed. The expressed intensity of GDF-9 in each staged follicles in the PCOS group is lower than that in the control group, and the lowing expressed intensities in the primary follicle stage and the secondary follicle stage are particularly evident (p<0.05). The expression of GDF-9 in granule cells in the PCOS group is lower than that in control group (p<0.05). And its expression in theca cells in the PCOS group is higher than that in control group (p<0.05). The expressed intensities between the two groups are no difference (p>0.05). The quantity of GDF-9 in the PCOS group is obviously less than that in control group detected by flow cytometry (p<0.01).6 COX-1 protein expression in ovarian PCOS: The immuno- histochemical results show that: The expression of COX-1 could be detected significantly in the granulosa cells and theca cells in the ovaries of both groups. In the PCOS group, the COX-1 expression in the theca cells is higher than that in the granulosa cells with significantly disparation (p<0.05). In the control group, the COX-1 expression in granulosa cells is higher than that in the theca cells with significantly disparation (p<0.01). The expression of COX-1 in PCOS group is higher than that in the control group with significantly disparation (p<0.01). But the expression of COX-1 in the granulosa cells comparing the two groups has no difference (p>0.05).Conclusion:1 Poretsky PCOS rat model was established successfully.2 It suggests that the abnormal expression of GDF-9 may be is one of the important factors in the delayed follicular development and stagnation of follicular mature in the PCOS patients.3 GDF-9 may cause the high levels of androgen in PCOS.4 It hints that the abnormal expression of COX-1 in local ovary of PCOS may be related to the pathogenesis of PCOS.