Hydrogen peroxide affects specific epithelial subpopulations in cultured rabbit lenses.
Hydrogen peroxide affects specific epithelial subpopulations in cultured rabbit lenses.
复制标题
DOI：
--
复制
发表时间：
1995-02
影响因子：
4.4
通讯作者：
J. Reddan;F. Giblin;D. Dziedzic;B. M. Wirebaugh;J. L. Peters
中科院分区：
文献类型：
--
作者：
J. Reddan;F. Giblin;D. Dziedzic;B. M. Wirebaugh;J. L. Peters
目的探讨过氧化氢对培养兔晶状体上皮细胞的影响。方法晶状体在含有单剂量0.03、0.1或0.2 mM H2O2的最小基本培养基中培养。3小时后，将培养基替换为无过氧化物的最低必需培养基。用0.5 mM的1,3-双（2-氯乙基）-1亚硝基脲（BCNU）处理晶体以降低谷胱甘肽还原酶的活性，然后再用0.03 mM的H2O2处理晶体，葡萄糖氧化酶使其保持不变。H2O2处理后，固定晶状体，制备整个上皮载具或处理晶状体进行电镜观察。结果单次接触0.03 mM H2O2后，细胞表现正常；0.1 mM H2O2无细胞毒性。暴露于0.2 mM H2O2后，赤道前区域细胞肿胀（30分钟），1小时后，赤道前区域细胞形成岛状。中央上皮细胞1小时正常，3小时肿胀，24小时死亡。48小时后，在赤道前和中部地区发现死亡细胞。上皮外周区域的细胞未表现出细胞毒性。如果用BCNU预处理晶状体，然后用维持水平的0.03 mM H2O2刺激，则在中部和赤道前区域诱导细胞毒性。外周区域的细胞在BCNU-H2O2处理下存活。结论晶状体外周区细胞对H2O2细胞毒性的抵抗能力强于中部和前赤道区细胞。在晶状体上皮亚群中，h2o2诱导损伤的抗氧化防御或修复系统似乎并不均匀分布。
PURPOSE To investigate the effect of hydrogen peroxide on the epithelial cells of cultured rabbit lenses. METHODS Lenses were cultured in minimum essential medium containing a single dose of 0.03, 0.1, or 0.2 mM H2O2. Three hours later the medium was replaced with peroxide-free minimum essential medium. Lenses were also treated with 0.5 mM 1,3-bis(2-chloroethyl)-1 nitrosourea (BCNU) to lower the activity of glutathione reductase and then exposed to 0.03 mM H2O2 maintained nearly constant by glucose oxidase. After H2O2 treatment, lenses were fixed and whole mounts of the epithelium were prepared or lenses were processed for electron microscopy. RESULTS Cells exposed to a single dose of 0.03 mM H2O2 appeared normal; 0.1 mM H2O2 was not cytotoxic. Exposure to 0.2 mM H2O2 elicited swelling in cells in the pre-equatorial region (30 minutes) followed by the formation of islands of cells in the pre-equatorial region at 1 hour. Central epithelial cells appeared normal at 1 hour, were swollen at 3 hours and dead at 24 hours. By 48 hours, dead cells were found in the pre-equatorial and central regions. Cells in the peripheral region of the epithelium did not exhibit cytotoxicity. If lenses were pretreated with BCNU and then challenged with a maintained level of 0.03 mM H2O2, cytotoxicity was induced in the central and pre-equatorial regions. Cells in the peripheral region survived BCNU-H2O2 treatment. CONCLUSIONS Cells in the peripheral region of cultured lenses were more resistant to H2O2 cytotoxicity than cells in the central and pre-equatorial regions. The antioxidant defense or repair systems for H2O2-induced damage do not appear to be uniformly distributed in subpopulations of the lens epithelium.