The Effect of Electroacupuncture on the Expression of VEGF and VEGFR2 in the Uterus of the Rat Model of Ovulation Induction

OBJECTIVE To observe the effect of electroacupuncture on the expression of VEGF and VEGFR2 in the uterus of the rat model of ovulation induction and to investigate the possible mechanism. METHODS Female SD rats aged 10 weeks were divided into control， model and treat groups randomly， 10 in each group. The model group and the treatment group were peritoneal injected with pregnant horse serum gonadotrophin (PMSG) of 20U and injected of the same dose of human chorionic gonadotropin(hCG) after 48h， and then cohabitated with male SD nice until next morning. A week before cohabitation， the treat group received a consecutive electroacupuncture treatment for 7d(dilatational wave of 2/15Hz for 30min and stimulative intensity of 1mA). The animals were sacrificed 3.5d after the cohabitation. The uterine tissue was taken to observe the morphological change， immunehistochemical method was used to inspect the expression of VEGF and VEGFR2， and qPCR technology was used to determine the expression of VEGF and VEGFR， with the calculation by 2 -△△Ct . RESULTS Macroscopic observation: the surface in control group was regular and smooth; the model group was intumescentia， dull-red and hyperaemia; the treatment group was slightly swollen， rosy and no congestion. The expression of VEGF and VEGFR2 were observed in the 3 groups by immunohistochemical method， with no significant difference in average optical density， but differences in the expression distribution. Compared with the control group， the expression distribution of stromal cells and glands in the model group was more extensive， and the expression of VEGFR2 in myometrium increased significantly(P<0.05). The electroacupuncture treatment inhibited the the expression of VEGFR2 significantly(P<0.05). The expression of VEGF mRNA in uterine tissues of model group was 0.68 times of control group， with significant declining trend; the treat group was 0.88 times of model group， with significant increasing trend. The expression of VEGF2 mRNA in uterine tissues of model group was 0.46 times of control group， with significant declining trend; the treat group was 0.82 times of model group， with significant increasing trend. CONCLUSION The electroacupuncture can adjust the expression of VEGF and its receptor in the uterine tissue of ovulation induction rat model， thus regulate the synchronization of the endometrial planting window caused by hormone.