OBJECTIVETo observe the intervention effects of electroacupuncture at "Yishu" (EX-B 3) on rats with type-2 diabetes mellitus (T2DM), so as to provide experiment references for acupuncture to treat T2DM.

METHODSAmong seventy male Wistar clean-grade rats, 8 rats were randomly selected into a control group; the rest rats were made T2DM model. Fifty-two rats which were successfully made T2DM model, according to randomized block method, were divided into a model group (10 rats), a medication group (10 rats), an electroacupuncture at "Shenshu" (BL 23) group (11 rats), an electroacupuncture at "Pishu" (BL 20) group (10 rats) and an electroacupuncture at "Yishu" (EX-B 3) group (11 rats). Seven days after successful establishment of model, the rats in the model group were fixed in the self-made rat bag without receiving any treatment; the rats in the medication group, according to body mass (10 mL/kg), were treated with intragastric administration of glimepiride; the rats in all the electroacupuncture groups were treated with electroacupuncture at "Shenshu" (BL 23), "Pishu" (BL 20) and "Yishu" (EX-B 3), respectively. The continuous wave was selected with a frequency of 15 Hz and a current intensity of 4 to 6 mA. The treatment was given 20 min per treatment, once a day, 5 treatments per week for continuous 4 weeks. Before the establishment of model and continuous 4 weeks after the intervention, blood samples were collected from rats' caudal vein, and fasting blood glucose (FBG) was measured with FBG device each week. After the last intervention, the rats were killed and hypothalamus, pituitary and adrenal gland were collected. The colorimetric method was applied to measure the contents of triglyceride (TG), cholesterol (TC), high-density lipoprotein (HDL-C) and low-density lipoprotein (LDL-C); radioimmunoassay was used to test the contents of glycated serum protein (GSP), fasting insulin (FINS), corticotropin-releasing hormone (CRH), adrenocorticotropic hormone (ACTH) and cortin (CORT).

RESULTSFour weeks after the intervention, except that the rat's body mass in the normal group continued to increase, body mass in the model group, medication group and each electroacupuncture group were significantly reduced (P<0.01, P<0.05). Compared with the model group, the FBG in the electroacupuncture at "Pishu" (BL 20) group and electroacupuncture at "Yishu" (EX-B 3) group were obviously reduced (P<0.05, P<0.01); FBG in the electroacupuncture at "Yishu" (EX-B 3) group was lower than that in the medication group and electroacupuncture at "Shenshu" (BL 23) group (both P<0.05). The contents of TG, HDL-C and LDL-C in the electroacupuncture at "Yishu" (EX-B 3) group were reduced (P<0.05, P<0.01), the content of TG was significantly lower than that in the medication group and electroacupuncture at "Shenshu" (BL 23) group (both P<0.05), the content of LDL-C was significantly lower than that in electroacupuncture at "Shenshu" (BL 23) group (P<0.05). Insulin sensitivity index (ISI) in the medication group, electroacupuncture at "Pishu" (BL 20) group and electroacupuncture at "Yishu (EX-B 3)" group were evidently increased (P<0.05, P<0.01); ISI in the medication group was lower than that in the electroacupuncture at "Yishu" (EX-B 3) group (P<0.05). The content of CRH in the electroacupuncture at "Yishu" (EX-B 3) group was lower than that in the medication group and electroacupuncture at "Shenshu" (BL 23) group (P<0.05, P<0.01); the content of CORT in the electroacupuncture at "Yishu" (EX-B 3) group was lower than that in the medication group and electroacupuncture at "Pishu" (BL 20) group (both P<0.05).

CONCLUSIONElectroacupuncture at "Yishu" (EX-B 3) could reduce the level of CORT to improve the insulin resistance in rats with T2DM, improve insulin sensitivity index, regulate blood lipid metabolism and relieve the hyperactivity of the HPA axis.