To observe the effects of electroacupuncture (EA) on hormone secretion function of ovarian granulosa cells and theca cells, as well as the expression changes of kisspeptin and kiss1r in rats with polycystic ovarian syndrome (PCOS), so as to explore the mechanism of EA for relieving ovarian dysfunction in PCOS rats. Forty-eight SD female rats were randomly divided into control group, model group, EA group and flutamide group, with 12 rats in each group. PCOS rat model was replicated with the gavage of letrozole (0.1 mg/mL, 10 mL•kg-1•d-1). In the EA group, EA (2 Hz, 2 mA) was used to stimulate "Guanyuan" (CV4) for 20 min each time. In the flutamide group, flutamide solution (50 mg•kg-1•d-1) was administrated by gavage. The treatments were given once daily for 14 days in each group. After the modeling and treatment, the body and ovarian weights of the rats were measured, and the ovarian index was calculated. Using HE staining, the morphological changes of ovary were observed. ELISA was adopted to detect the contents of testosterone (T), luteinizing hormone (LH) and estradiol (E2) in serum, the contents of E2 and T in the culture medium of ovarian granulosa cells and theca cells, as well as the content of kisspeptin in the ovarian tissue. The positive expression of kisspeptin in ovary was observed by immunohistochemical method, and the protein expression of its receptor kiss1r was detected by Western blot. Compared with the control group, the body and ovarian weights, ovarian index, the contents of T and LH in serum and that of T in the culture medium of theca cells, as well as the content and positive expression of kisspeptin in ovary were all increased (P<0.01, P<0.05); and the content of E2 in the culture medium of granulosa cells was decreased (P<0.01) in the model group. When compared with the model group, in the EA and flutamide groups, the body and ovarian weights, ovarian index, the contents of T and LH in serum and that of T in the culture medium of theca cells, as well as the content and expression of kisspeptin in ovary were all decreased (P<0.01, P<0.05); and the content of E2 in the culture medium of granulosa cells was increased (P<0.05, P<0.01). EA regulates the serum sex hormone levels, the secretion function of the ovarian granulosa cells and theca cells, and the ovarian kisspeptin/kiss1r protein expression in PCOS rats, showing the similar effect as receptor blockade intervention. It is suggested that the improvement of EA in ovarian dysfunction of PCOS rats may be related to the kisspeptin/kiss1r system.
Read full abstract