Objective To explore the possible mechanism of electroacupuncture improving insulin resistance obesity. Methods Of 48 healthy Wistar male rats

8 were randomly selected to be fed with normal diet as the normal group

and the remaining 40 were fed with high-fat diet to establish an insulin resistance obesity model. After 8 weeks

the successfully modeled rats were randomly divided into a model group

an electroacupuncture group and a sham electroacupuncture group

with 8 rats in each group. In the electroacupuncture group

the points "Fenglong（ST40）"

"Zhongwan（CV12）"

"Guanyuan（CV4）"

and "Zusanli（S36）" were selected

and the electroacupuncture device was used for 2 Hz

1 mA

continuous wave

30 min each time

once every other day; the sham electroacupuncture group was given 5 mm shallow acupuncture 5 mm beside above-mentioned acupoints

and the clamping electrode is not energized. All groups were intervened for 8 weeks. The body weight and 24 h food intake of rats were measured at 0

2

4

6

and 8 weeks of intervention. After the experiment

the levels of serum insulin

leptin and glucose infusion rate（GIR） of rats in each group were measured

immunohistochemical method was used to detect the relative expression of leptin-induced phosphorylation signal transducer and activator of transcription 3（p-STAT3）. Western blotting was used to determine the expression of p-STAT3 protein in nodose ganglion and arcuate nucleus. Results Compared with the normal group

24 h food intake and body weight at 0

2

4

6

and 8 weeks of the rats in the model group increased

while the serum insulin and leptin levels increased

and the GIR decreased; the expression of p-STAT3 in the dorsal nucleus and ambiguous nucleus decreased

and the expression of p-STAT3 protein in the nodose ganglion and arcuate nucleus also decreased（P<0.01）. Compared with the model group and the sham electroacupuncture group

24 h food intake and body weight at 6 weeks and 8 weeks decreased in the electroacupuncture group

serum insulin and leptin levels decreased

and GIR increased; the expression of p-STAT3 in the vagus motor dorsal nucleus and the ambiguous nucleus increased

and the expression of p-STAT3 protein in the nodose ganglia and arcuate nucleus also increased significantly（P<0.05 or P<0.01）. Conclusion Electroacupuncture can effectively regulate the sensitivity of the central nervous system to leptin

which may be one of the mechanisms for improving insulin resistance and obesity.