Dezawa M, Mo X, Oshitari T, Takano M, Meyer-Rochow V B, Sawada H, Eguchi E
Department of Anatomy, Yokohama City University School of Medicine, 3-9 Fukuura, Kanazawa-ku, Yokohama 236-0004, Japan.
Acta Neurobiol Exp (Wars). 2001;61(2):85-91. doi: 10.55782/ane-2001-1388.
Effects of light and darkness on the apoptosis of retinal ganglion cells (RGCs) in young carp were measured by TUNEL method after transection of the optic nerve. Following the operation, the fish were kept under one of four regimens; constant darkness (DD), constant light (LL), 12 hr light and 12 hr dark (LD) and 3 hr of flickering light followed by 21 hr in the dark (FL). On day 3, the highest ratio of apoptotic RGCs was seen under conditions of DD, followed by LL, LD, and FL. On day 6, the percentages of apoptotic RGCs were lower under every experimental condition than what they had been earlier on day 3, but the same ranking order was maintained. Immunohistochemically it could be shown that phosphorylated ERKs were more intensively localized in FL rather than DD retinas. The results suggest that illumination regimens, and in particular cyclic diurnal light/dark changes, have an influence on the degree of apoptosis of damaged RGCs, and that inhibition of apoptosis is correlated with the higher expression of phosphorylated ERKs.
通过TUNEL法在视神经横断后测量光照和黑暗对幼鲤视网膜神经节细胞（RGCs）凋亡的影响。手术后，将鱼置于四种饲养方案之一；持续黑暗（DD）、持续光照（LL）、12小时光照和12小时黑暗（LD）以及3小时闪烁光后接着21小时黑暗（FL）。在第3天，在DD条件下观察到凋亡RGCs的比例最高，其次是LL、LD和FL。在第6天，每个实验条件下凋亡RGCs的百分比都比第3天早些时候低，但保持相同的排名顺序。免疫组织化学显示，磷酸化的细胞外信号调节激酶（ERK）在FL视网膜中比在DD视网膜中定位更密集。结果表明，光照方案，特别是昼夜循环的光/暗变化，对受损RGCs的凋亡程度有影响，并且凋亡的抑制与磷酸化ERK的较高表达相关。
