金钠多、灯盏花素对N-甲基-N-亚硝脲诱导SD大鼠视网膜变性的保护作用

Ginaton and Breviscapin rescueing N-Methyl-N-nitrosourea-induced retinal deg eneration in SD rats

目的 观察金钠多 (Gin)、灯盏花素 (Bre)对N 甲基 N 亚硝脲 (MNU)诱导SD大鼠视网膜变性的保护作用及机制。方法 雌性SD大鼠随机分为正常对照组、模型组、Gin组和Bre组。其中Gin又分大剂量和中剂量组 ,Bre分大剂量、中剂量和小剂量组。于生后 47d开始腹腔注射给药 ,每日 1次 ,连续给药 4d和 10d ,并于生后 50d腹腔注射MNU 60mg/kg。在MNU处理 2 4h和 7d后处死动物 ,取眼球。通过视网膜形态学分析测量周边视网膜的总厚度 ,TUNEL试剂盒检测光感受器细胞凋亡。结果 MNU处理 7d后 ,模型组周边视网膜的总厚度为 3 6μm ,Gin组和Bre组分别为 44、3 7、58、43和 3 9μm。MNU处理 2 4h后 ,模型组周边视网膜的光感受器细胞凋亡指数为 (3 8 0± 3 6) % ,Gin组和Bre组分别为 (2 6 3± 2 7) %、(3 7 4± 2 9) %、(19 4± 1 9) %、(2 8 0± 3 0 ) %和 (3 6 9± 2 1) %。结论 Gin和Bre对MNU引起的周边视网膜损伤有一定的保护作用 ,呈剂量依赖性 ,其作用机制是通过抑制光感受器细胞发生凋亡。

Object iv eTo observe the effect of Ginaton ( Gin ) and Breviscapin ( Bre ) on N-methyl -N-nitrosourea (MNU )-induced retinal degeneration in SD rats and its mechani sm.MethodsFemale SD rats were randomly divided into:①control group,②model group,③Gin groups,in which the rats were subdivided into big and medium groups and ④Bre groups,including big ,medium and small groups.50-day SD rats receive d a single intraperitoneal injection of 60 mg/kg MNU and were sacrificed at 24 h and 7 d after the treatment.Gin and Bre were injected intraperitoneally in 47- day SD rats for 4 d and 10 d once a day.Peripheral retinal damage was evaluated based on retinal thickness change at the 7th d after MNU treatment,and the apopt otic index of the photoreceptor cells was detected by TUNEL labeling at 24 h fo llowing MNU treatment.ResultsTotal retinal thickness in 7 d after MNU inject ion was 36 μm in model group.Gin and Bre injection increased these values to 44 ,37,58,43 and 39 μm,respectively.In the peripheral retina,the apoptotic index a t 24 h in post-MNU was(38 0±3 6)%,but(26 3±2 7)%,(37 4±2 9)%,(1 9 4±1 9)%,(28 0±3 0)%and(36 9±2 1)% in Gin and Bre groups,respecti vely.ConclusionGin or Bre can effectively suppress MNU-induced peripheral r etinal damage by anti-apoptosis in a dose-dependent manner.However,no protecti ve effect on MNU-induced central retinal damage is found.