方法：采用STZ腹腔注射制作糖尿病大鼠模型，在造模后6mo内各时点(2wk； 1，2，3，4，5，6mo)采用伊文思蓝灌注示踪显示血-视网膜的渗漏情况，在造模后3mo开始用中药芪灯明目胶囊(低中高剂量组分别给予125，250，500mg/kg体质量剂量的胶囊内容物灌胃)，对照组用安多明胶囊(200mg/kg体质量剂量，相当于10倍成人剂量)，灌胃3mo，观察药物对 BRB的影响。

结果：STZ糖尿病大鼠在2wk即可出现BRB的损害，并随着高血糖状态的持续而不断加重。对造模3mo STZ糖尿病模型大鼠连续灌胃中药芪灯治疗3mo，结果提示：中药芪灯对STZ糖尿病BRB有保护作用，可明显减少视网膜血管的渗漏。

结论：STZ糖尿病模型大鼠在早期即可出现BRB损害，并随着高血糖的持续而加重，中药芪灯明目胶囊可减少高血糖导致的BRB损害。

METHODS: We induced diabetic rat model by peritoneal injection of STZ, after the blood glucose raised, we used Evans blue to trace the leakage of blood-retina barrier(BRB)every month. After blood glucose rose three months later, we treated the Chinese medicine group diabetic rat with Qidengmingmu capsule. There were three groups of different dose, low dose group of 125mg/kg, middle dose group of 250mg/kg, high dose group of 500mg/kg. The control group was treated with calcium dobesilate(200mg/kg). After three months treated by medicine, the leakage of rat blood-retina barrier was evaluated.

RESULTS: The damage of BRB and visual function occurred at two week after the blood glucose rose, and the damage aggravated with the continuing of high diabetic. But after the Chinese medicine treated three months, the rat's retina vessel leakage was reduced.

CONCLUSION: BRB break down and visual acuity damage appears in early phase of STZ diabetic rat and get worse as the hyperglycemia keep on. The Chinese medicine Qidengmingmu capsule can prevent the vessel leakage by damage of BRB.