Light treatment enhances photoreceptor survival in dystrophic retinas of Royal College of Surgeons rats.
Light treatment enhances photoreceptor survival in dystrophic retinas of Royal College of Surgeons rats.
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发表时间：
1999-09
影响因子：
4.4
通讯作者：
I. Nir;Changdong Liu;Rong Wen
中科院分区：
文献类型：
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作者：
I. Nir;Changdong Liu;Rong Wen
目的确定强光治疗是否能引起保护性反应，提高遗传性视网膜变性大鼠的光感受器存活率。方法用130只白光或绿光照射RCS大鼠10~12h。将处于低周期光照下的未处理的凋落物作为对照对象。光感受器存活通过光感受器核的定量分析和细胞组织的超微结构评估来确定。在基因和蛋白水平检测碱性成纤维细胞生长因子和睫状神经营养因子的基因表达。结果RCS大鼠出生后第23天单次强光照射可显著提高光感受器存活率。超微结构分析显示，光处理的视网膜内节段完整，而未处理的视网膜仅观察到残留的内节段。到P42时，光处理组大鼠视网膜后部可见大量存活的细胞核，而未处理的RCS大鼠视网膜中剩余的核大部分高度固缩。单次强光照射后2.5d，RCS大鼠视网膜bFGF基因表达明显高于未处理组。到P42时，治疗组视网膜中bFGF蛋白水平仍显著高于对照组。结论外源性碱性成纤维细胞生长因子可促进RCS大鼠视网膜光感受器存活。因此，在光处理的RCS大鼠视网膜中检测到的bFGF表达的增加可能是对光应激的保护性反应，这支持了观察到的光处理RCS大鼠视网膜光感受器的拯救。
PURPOSE To determine whether treatment with bright light elicits a protective response that enhances photoreceptor survival in Royal College of Surgeons (RCS) rats with inherited retinal degeneration. METHODS RCS rats were illuminated for 10 to 12 hours with 130 foot-candles (fc) of white or green light. Untreated littermates that were kept under low cyclic light levels were used as control subjects. Photoreceptor survival was determined by quantitative analysis of photoreceptor nuclei and ultrastructural assessment of cellular organization. Basic fibroblast growth factor (bFGF) and ciliary neurotrophic factor (CNTF) gene expression were determined at the mRNA and protein levels. RESULTS Treatments of RCS rats with a single dose of bright light on postnatal day 23 (P23) greatly enhanced photoreceptor survival. Ultrasturctural analysis revealed intact inner segments in light-treated retinas, whereas in untreated retinas only remnants of inner segments were observed. By P42, numerous viable nuclei were counted in the posterior retina of light-treated rats, whereas most of the remaining nuclei in untreated RCS rat retinas were highly pyknotic. At 2.5 days after treatment with a single dose of bright light, bFGF gene expression was significantly higher than in untreated RCS rat retinas. By P42, bFGF protein levels were still significantly higher in the treated retinas. CONCLUSIONS Exogenous bFGF has been shown to promote photoreceptor survival in the RCS rat retina. Thus, the increased bFGF expression that was measured in the light-treated RCS rat retinas may be a protective response to light stress, which supports the observed rescue of photoreceptors in light-treated RCS rat retinas.