晶状体上皮细胞凋亡与过氧化氢诱导白内障形成研究

目的 探讨晶状体上皮细胞凋亡与皮质性白内障形成的关系。方法用200μmol／L过氧化氢(H2O2)诱导离体兔晶状体白内障形成，TUNEL法检测H：0：作用1，6，18，24，48h的晶状体上皮凋亡细胞，同时测定晶状体超氧化物歧化酶(SOD)活性。结果H2O2作用1h，晶状体保持透明，未发现凋亡上皮细胞。随着作用时间的延长，凋亡上皮细胞数量逐渐增多，晶状体逐渐变混浊。SOD活性早期无变化，18h后逐渐降低。结论晶状体上皮细胞凋亡是皮质性白内障形成的细胞学基础，其发生先于晶状体抗氧化机制的变化。

An experimental study oflens epithelial cells apoptosis and hydrogen peroxide induced cataract formation

ObjectiveTo explore the relationship between lens epithelial cells apoptosis and cortical cataract formation.MethodsCultured rabbit lenses were treated with 200 μmol/L hydrogen peroxide(H2O2)to establish cataract models in vitro.The pacification of lenses was observed dynamically.The apoptotic epithelial cells of lens were determined by TdT labeling at 1,6,18,24 and 48 h treatment with H2O2,respectively.Lens superoxide dismutase(SOD)activity was determined at the same time.　ResultsThe lens transparence and the morphology of lens epithelial cells appeared normal,and no SOD activity alterations were observed in control at 48 h.The lenses remained transparent and no apoptotic cells were found at 1 h treatment with H2O2.The apoptotic epithelial cells appeared at 6 h,and the equatorial region of lens became completely opaque.The number of apoptotic epithelial cells gradually increased during incubation,and lens opacification gradually developed from the equatorial region to the center.The percent of apoptotic lens epithelial cells increased to 11.5% at 18 h and 34.3% at 24 h.A few apoptotic cells were detected from the anterior capsule at 24 h treatment with H2O2.At 48 h,a large number of apoptotic epithelial cells were detected from the capsule,only a few non-apoptotic cells left.By this time,the lens developed complete pacification.No lens SOD activity alterations were observed at 0 h and 6 h treatment with H2O2.Lens SOD activity was found declined at 18 h(P<0.01),and continued declining following incubation from 528.21 U/g at 18 h to 382.51 U/g at 48 h.ConclusionLens epithelial cells apoptosis is the cytological base of cortical cataract formation that happened prior to the change of antioxidation mechanism in lens