Objective: To observe the effect of electroacupuncture (EA) on the expression of NPY and its mRNA in hypothalamus of streptozotocin (STZ)-induced diabetes mellitus (DM) rats. Methods: Forty-three Wistar rats (180～220 g) were assigned to normal control group (n=13)

model group (n=11) and EA group (n=11). DM model was established by intraperitoneal injection of STZ(50 mg/kg). EA (100 Hz

0.5～2 mA

15 min) was applied to bilateral “Yishu”

“Zusanli”(ST 36) and “Guanyuan”(CV 4)

once daily and with 6 sessions being a therapeutic course. After two courses of treatment

the rats were sacrificed to test the expression of NPY and its mRNA in hypothalamus with immunohistochemical and in situ hybridization methods respectively. Results: Compared with normal group (n=5)

OD values of NPY expression positive fibers in hypothalamic paraventricular nucleus (PVN) and arcuate nucleus (ARC)

the OD value and the total area of NPYmRNA expression in lateral hypothalamus (LH) increased significantly (P<0.05) in DM rats of model group (n=5). Comparison between model group and EA group (n=5) showed that OD values of NPY expression positive fibers in PVN and ARC

the OD value and the total area of NPYmRNA expression in LH of the later group were significantly lower than those of the former group (P<0.05)

displaying that after EA

the concentration of NPY and expression of its mRNA in hypothalamus decreased obviously. Conclusion: EA can reduce the level of NPY and its synthesis in hypothalamus of STZ-induced diabetic rats

which may contribute to its effect for improving energy metabolism of diabetes.