糖尿病大鼠冠状动脉超氧阴离子生成部位的研究

The studies on location of producing superoxide anion in coronary arteries of diabetic rats

目的探讨糖尿病大鼠高血糖状态下冠状动脉超氧阴离子(O2-)生成部位。方法用链脲佐菌素制备大鼠糖尿病模型后取冠状动脉和在高糖下培养大鼠冠状动脉24 h,免疫荧光组织化学染色及激光扫描共聚焦显微镜检测冠状动脉中O2-生成部位。结果糖尿病大鼠冠状动脉内皮组织、外膜组织和平滑肌组织O1-生成量均较对照组升高,二者比较差异有统计学意义(t内=24．719,P<0．01;t外=14．206,P<0．01;t平:11．784, P<0．01)。高糖培养24 h,大鼠冠状动脉内皮组织O2-生成量比对照组升高,二者比较差异有统计学意义(t内= 2．183,P<0．05);外膜组织和平滑肌组织O2-生成量与对照组比较,差异无统计学意义(t外=1.439,P>0．05;t平= 1．662,P>0．05)。结论糖尿病短期高血糖状态下,O2-只产生于内皮细胞,长期高血糖状态下,O2-由内皮细胞经跨细胞转移转运到平滑肌细胞。

Objective To discuss the producing location of coronary arteries superoxide anion under hyperglycemia status. Methods Rat diabetic model was established by intraperitoneal injection of streptozotocin; rats coronary arteries were cultured in DMEM （high glucose） for 24 h. After immunofluorescent histochemical staining, the coronary arteries were observed under confocal microscopy as for where superoxide anion was rpoduced. Results The average superoxide anion densities in endothelium （e）, adventitia （a） and smooth （s） muscle of coronary artery in diabetes model group respectively increased compared with that in control group （te = 24.719, P 〈 0.01; ta = 14.206, P 〈 0.01; ts = 11.784, P 〈 0.01, respectively） ;The average superoxide anion density in endothelium of coronary artery cultured in high glucose for 24 h was higher than that in control group （te = 2.183, P 〈 0.05）, but that of adventitia and smooth muscle made no difference（ta = 1.439, P〉 0.05; ts = 1.662, P〉 0.05, respectively）. Conclusions Superoxide anion is produced in coronary artery endothelium only under hyperglycemia in a short period of time;but after a long period of time,due to cell membrane transportation function, superoxide anion may be transported from endothelium to smooth muscle across cell membrane.