视神经纤维离断对成年大鼠视网膜PTEN/mTOR活性的影响

The effect of optic nerve axotomy on retinal PTEN/mTOR activity of adult rat

目的 探讨视神经纤维离断（ONA）对成年大鼠视网膜第十号染色体缺失与磷酸酶和张力蛋白同源基因（PTEN）/哺乳动物雷帕霉素靶蛋白（mTOR）活性的影响.方法 球后视神经钳夹法制作成年大鼠右眼ONA模型,对侧眼作为正常对照组.ONA后7d和14 d,分别以Western-blot、免疫荧光检测视网膜PTEN、磷酸化核糖体S6蛋白（pS6）的表达.结果 ONA后7d和14 d,大鼠视网膜PTEN的表达均增高,与正常对照组的差异均有统计学意义（P =0.0065、0.0219）;而同期pS6的表达降低,与正常对照组的差异均有统计学意义（P=0.0003、0.0000）.结论 ONA可上调成年大鼠视网膜PTEN的表达而抑制mTOR的活性.

Objective To investigate the effect of optic nerve axotomy （ONA） on phosphate and tension homology deleted on chromsome ten （PTEN）/mammalian target of rapamycin （mTOR） activity of adult rat retina.Methods Right ONA models of adult rats were established by crushing optic nerve and evaluated with FluoroGoldTM labeling retinal ganglion cells （RGCs） retrogradely.The left eyes were intact and served as normal control group.The expression of PTEN and phosphorylated ribosomal protein S6 （pS6）,biochemical marker of mTOR activity,were measured with Western blotting assay and immunofluorescence respectively at 7 and 14 days after ONA.Results The completeness of ONA was confirmed by FluoroGold^TM retrograde labeling.Compared with normal control group,the expression of PTEN of experimental group was significantly increased at 7 and 14 days after ONA （P =0.0065,0.0219）,meanwhile the expression of pS6 of experimental group was significantly decreased （P =0.0003,0.0000）.Conclusion ONA can stimulate the expression of PTEN and subsequently diminish the mTOR activity of adult rat retina.