不同时期糖尿病对大鼠血脑屏障内皮细胞葡萄糖转运蛋白-1的影响

The effect of diabetes on expression of the glucose transporter-1 in blood brain barrier endothelial cell of diabetic rats at different time points

目的 研究不同时期糖尿病对大鼠血脑屏障（BBB）内皮细胞葡萄糖转运蛋白-1（glucose transporters-1，GLUT-1）表达的影响。方法 雄性SD大鼠40只，随机分为正常对照组（2、10个月）、糖尿病组（2、10个月），每组20只。用链脲霉素（streptozotocin，50mg／kg）静脉一次性注射制备糖尿病模型。分别于2个月和10个月后各处死10只，均取前额叶皮质。用免疫组织化学方法检测BBB微血管内皮细胞GLUT-1表达。结果 2个月糖尿病组GLUT-1阳性微血管数为（4．3±0．9）个（低倍视野，下同），与2个月正常对照组[（6．4±1．7）个]比较，差异具有统计学意义（t=7．586，P〈0．01）。10个月糖尿病组GLUT-1阳性微血管数为（8．4±1．4）个，与10个月正常对照组[（5．8±1．7）个]比较，差异具有统计学意义（t=15．922，P〈0．01）。结论 早期糖尿病可引起BBB内皮细胞GLUT-1蛋白表达的下调。晚期糖尿病可引起BBB内皮细胞GLUT-1蛋白表达的上调。

Objective To investigate the effect of diabetes on the expression of the glucose transporter （ GLUT-1 ） in blood brain barrier （BBB） endothelial cell at different time points. Methods Forty male SD rats were randomly divided into normal control and diabetic group. Diabetic model of SD rats was established by intravenous streptozotocin（50 mg/kg） injection. Ten rats in each group were sacrificed on the 2nd month and 10th month respectively. The rat＇ s prefrontal cortex was removed to observe the expression of GLUT-1 in BBB EC with immunohistochemical（IHC） staining. Results By IHC method, the number of GLUT-1 positive microvessels was significantly decreased in diabetic group in the 2nd month （4. 3±0. 9） compared with that of control group （6. 4 ± 1.7, t =7. 586,P 〈0. 01 ） ; the number of GLUT-1 positive microvessels was significantly increased in the diabetic group in the 10th month （ 8.4 ± 1.4 ） compared with that of control group （5. 8 ± 1.7, t = 15. 922, P 〈 0. 01 ）. Conclusions Short-term diabetes GLUT-1 expression in BBB EC is downregulated in early stage, while it is upregulated in advanced stage.