摘要目的 探讨不同波长光照射对rd12和C57BL/6J小鼠视网膜光损伤的影响.方法 取rd12和C57BL/6J小鼠各32只,随机分成对照组、白光组、中波长光(505 nm)组和短波长光(405 nm)组,各组光照强度为(800±130) Lux,每天照射12h,持续7d.于光照前1d和光照后1、4、7d进行视网膜电流图(ERG)检测,光照7d后通过活体组织氧化应激活性氧(ROS)高质荧光检测ROS水平,免疫荧光法和蛋白质免疫印迹法检测抗过氧化物酶6(PRDX6)的表达,测定半胱氨酸蛋白酶-3(Caspase-3)活性.结果 C57BL/6J小鼠ERG反应随光照时间延长振幅逐渐降低,短波长光组下降最明显,光照后1、4、7d各组明视反应b波振幅率比较,差异均有统计学意义(F=4.412,5.082,9.980；P＜0.01).7d时对照组、白光组、中波长光组和短波长光组b波振幅率分别下降至(85±10)％、(70±19)％、(57±22)％、(46±19)％比较,其中,短波长光组与白光组比较,差异有统计学意义(t=3.19,P＜0.01).ROS含量测定显示,rd12小鼠各组ROS相对量比较,差异有统计学意义(F=16.08,P＜0.01),短波长光较其它组明显升高.PPDX表达比较,差异有统计学意义(F=7.214,P＜0.05).短波长光组较其它Caspase-3相对活性检测结果比较,差异有统计学意义(F=7.530,P＜0.05).C57BL/6J小鼠各组ROS含量、PRDX6蛋白及Caspase-3活性测定结果比较,差异均无统计学意义(F=3.625,1.993,1.133;P＞0.05).rd12与C57BL/6J小鼠各组比较,仅短波长光组Caspase-3相对活性检测结果差异有统计学意义(t=5.474,P＜0.05).结论 短波长光照射对小鼠视网膜具有损伤作用,其对rd12小鼠的影响较C57BL/6J小鼠显著.损伤机制可能与氧化损伤有关.

abstractsObjective To investigate the effects of lights with different wavelength on the retina of rd12 and C57BL/6J mice.Methods Thirty two rd12 mice and C57BL/6J mice were randomly divided into the control group,white light group,mid-wavelength light (505 nm) group and short-wavelength light (405nm) group,with eight mice in each group.Besides the control group,other groups were exposed to cycle illuminations [12 hours dark,12 hours (800 ± 130) Lux] for seven days to establish the model of retinal light damage.Electroretinogram (ERG) responses of all mice were recorded at the day before illumination and 1st,4th and 7th days after illumination.The eyes were enucleated at 7th days after illumination to assess levels of reactive oxygen species (ROS),expression of peroxiredoxin 6 (PRDX6),and activity of caspase-3.Results ERG amplitudes of all groups declined gradually in C57BL/6J mice,and the most significant effects was found in the short-wavelength light group.The amplitudes of photopic b-wave were significantly different at 1st,4th and 7th days (F=4.412,5.082,9.980; P＜0.01).The amplitudes of cone b-wave of the four groups decreased to (85±10) ％,(70±19) ％,(57±22) ％ and (46±19) ％ at 7th days,respectively,and were significantly different between white light group and short-wavelength light group(t=3.19,P＜0.01).The levels of ROS were significantly different in rd12 mice (F=16.08,P＜0.01),and elevated obviously in short-wavelength light group.The expressions of PRDX6 of retina were significantly different in rd12 mice (F =7.214,P＜0.05),and were decreased obviously in shortwavelength light group.The caspase-3 relative activity was significantly different in rdl2 retina (F=7.530,P＜0.05) ; but there was no significant difference in C57BL/6J mice (F=3.625,1.993,1.133; P＞0.05).The caspase-3 relative activity were significant different between rd12 mice and C57BL/6J mice in short wavelength light group (t =5.474,P＜0.05).Conclusions Short-waveleugth light can induce retinal damage of mouse retina,especially in rd12 mouse.The retinal light damage possibly relates to the oxidative damage.