[Electroacupuncture Combined with Clomiphene Promotes Pregnancy and Blastocyst Implantation Possibly by Up-regulating Expression of Insulin Receptor and Insulin Receptor Substrate 1 Proteins in Endometrium in Rats with PCOS].

Objective: To observe the effect of electroacupuncture (EA) intervention combined with clomiphene critate (CC) on the blastocyst implantation and pregnancy rate and expression of insulin receptor (INSR) and insulin receptor substrate 1 (IRS 1) proteins in the endometrium in rats with polycystic ovary syndrome (PCOS), so as to reveal its mechanisms underlying improvement of PCOS.

Methods: One hundred and twenty-five female SD rats were randomly divided into normal control, PCOS model, medication (CC), EA and EA+CC groups (=25 in each group, 15 for checking blastocyst implantation, and 10 for Western blot). The PCOS model was established by subcutaneous injection of Dehydroepiandrosterone (DHEA) and fed with high-fat diet. Rats of the normal control group were treated by subcutaneous injection of sesame oil and fed with the normal forage. EA stimulation was applied to "Zhongwan" (CV 12), "Guanyuan" (CV 4) and bilateral "Tianshu" (ST 25) for 30 min, 3 times a week, 5 weeks altogether. Rats of the CC and EA+CC groups were fed with CC (100 mg·kg·d) for 2 days after regular restriction (30 min, 3 times a week, 5 weeks altogether). The pregnancy was determined by vaginal smear tests and the number of blastocyst implantation determined by examination of the uterus after execution. The expression of INSR and IRS 1 proteins in the endometrium was detected by Western blot.

Results: The pregnancy rate and the number of blastocyst implantation were significantly lower in the model group than in the normal control group (<0.05), and remarkably increased after EA and EA+CC interventions (<0.05). The effects of EA+CC were obviously superior to those of simple EA and simple medication in raising the pregnancy rate and the number of blastocyst implantation (<0.05). No significant differences were found between the EA and CC groups in the pregnancy rate and the number of blastocyst implantation (>0.05). The relative expression levels of both INSR and IRS 1 proteins were markedly lower in the model group than in the normal control group (<0.05), and significantly higher in both EA and EA+CC groups than in the model group (<0.05). No significant differences were found between the model and the CC groups and between the EA and EA+CC groups in the expression levels of INSR and IRS 1 proteins (>0.05).

Conclusions: EA intervention can improve pregnancy rate and the number of blastocyst implantation in PCOS rats, which may be related to its effects in up-regulating the expression of INSR and IRS 1 proteins in the endometrium.