Objective: To evaluate the hypoglycemiceffect of extract from Tibetan medicine Berberis dictyophlla Cortex on postprandial blood glucose (PBG)

protection against oxidative stress

protection function on blood vessels in diabetic rats induced by streptozotocin(STZ)and to explore the mechanism. Method: The type 2 diabetic rat model was established by ip injection of STZ (40 mg·kg-1) on SD rats and the rats were fed with high sugar and high fat for 5 months.Then

the rats were divided into 8 groups and administered. During the experiment

the body weight

fasting blood glucose (FBG) were measured. After 30 days of administration

the superoxide dismutase (SOD)

malondialdehyde (MDA)

nitric oxide(NO)

cell adhesion molecule(ICAM-1)

angiotensin(ANGⅡ)

and other blood biochemical indexes were measured. Result: The B. dictyophlla cortex could reduce significantly the level of fasting blood glucose

ICAM-1 and ANGⅡexpression. The retinas were taken and observed by histopathological analysis

the tissue injury attenuated compared with the model group. The contents of SOD in serum of group were higher while MDA was lower than the model group. Conclusion: DR of B. dictyophlla cortex group was obviously better compared with the model group. The extract of B. dictyophlla cortex can improve effectively retinopathy of the rats

relieve the degree and development of DR and regulate function in the whole. All in all

Berberis Cortex showed the effect of prevention and therapy of DR.