【作者】 张新芳；

【导师】 张虹；

【作者基本信息】 华中科技大学 ， 眼科学， 2006， 硕士

【摘要】 目的研究大鼠糖尿病性白内障(diabetic cataract, DC)晶状体上皮细胞(lens epithelial cells, LECs)水通道蛋白-1(aquaporin-1 , AQP1)表达水平的变化及其与晶状体上皮细胞钙蛋白酶II(Calpain -2)表达水平、晶状体中Ca2+含量变化的关系。方法给Wistar大鼠注射链脲佐菌素(streptozotocin, STZ)建立糖尿病模型,根据晶状体混浊程度将白内障分为0～IV期。每周在裂隙灯显微镜下观察并记录拍照晶状体的混浊情况;将各期白内障大鼠的一侧眼球制成石蜡切片,光镜下观察晶状体的组织学变化;应用免疫组织化学方法和计算机图像分析技术对LECs表达的AQP1、Calpain-2进行检测。摘取另一侧眼球晶状体,用SpectrAA–40型原子吸收光谱仪测定Ca2+浓度。结果组织学观察,正常对照组晶状体结构正常,随着实验时间延长,实验组晶状体混浊逐渐加重,白内障I～IV期晶状体结构破坏逐渐加重;随着糖尿病发展和晶状体混浊程度的加重,LECs胞膜表达AQP1逐渐减少,而LECs胞浆表达的Calpain-2及晶状体Ca2+浓度逐渐增加。结论糖尿病大鼠晶状体上皮细胞膜AQP1的活性表达减少与晶状体上皮细胞胞浆Calpain-2的活性表达增加及晶状体Ca2+浓度增加关系密切。更多还原

【Abstract】 Objective To investigate the expression change of aquaporin-1 ( AQP1 ) in the membrane of lens epithelial cells (LECs) and the relation between this change and the expression of Calpain-2 in the cytoplasm of lens LECs and the total Ca2+ level in lenses of rat diabetic cataract( DC ).Methods An animal model of diabetes was induced by a single intravenous dose of streptozotocin (STZ, 60mg/kg body weight) in 2-month-old male Wistar rats. The transparency of all lens were examined under microscope and photographied every week. The eyeballs of both sides were extracted periodically from each experimental groups and control group. The eyeballs of one side were made into paraffin sections. The histological changes were examined under light microscope. Immunohistochemical techniques and computer-imaging analysis were used to localize and semi-quantify the expression of AQP1 and Calpain-2 in LECs. The lenses of other side were isolated and the concentration of Ca2+ was determined by a SpectrAA–40 atomic absorption spectrophotometer.Results All lenses in control group remained transparency and all lenses in experiment groups developed cataract of different stages. The breakage of the lens structure was gradually aggravated from stage I to stage IV. The expression of AQP1 on the cell membrane decreased significantly before the DC occurred and decreased gradually with the diabetes development. The elevated level of Calpain-2 in the cytoplasm of LECs and the increased ion concentration of Ca2+ in lenses were observed before lens opacification began. The expression of Calpain-2 increased gradually with the diabetes development and the concentration of Ca2+ did so.Conclusion Decreased expression of Aquaporin-1 in the membrane of LECs of rat diabetic cataract were closely correlated with elevated expression of Calpain-2 in the cytoplasm of LECs and increased ion concentration of Ca2+ in lens.更多还原