霍乱毒素及妊娠对金黄地鼠视网膜节细胞再生的作用

Cholera toxin and pregnancy promote regeneration of the retinal ganglion cells in golden hamster

目的：观察霍乱毒素（CTx）及妊娠对成年金黄地鼠视神经扎断后视网膜节细胞（RGCs）轴突再生的促进作用。方法：确定成年金黄地鼠交配3d后，扎断视神经（ON）近端，玻璃体内注射CTx。动物随机分为实验组和对照组：对照组为单纯扎断ON为损伤组、损伤PBS组；实验组分为CTx组与妊娠后扎断ON妊娠损伤组与妊娠CTx组。术后动物存活3周。用荧光金逆行标记再生的视网膜节细胞（RGCs），在荧光镜下观察视网膜平铺片再生RGCs的数量变化，并比较实验组各组再生RGCs的周长。结果：CTx组、妊娠损伤组、妊娠CTx组视网膜再生RGCs平均数比损伤组及PBS组增加，差异具有统计学意义。妊娠CTx组比CTx组、妊娠损伤组视网膜再生RGCs平均数增加。实验组各组再生的RGCs周长相比差异无统计学意义。结论：妊娠及玻璃体注入CTx具有促进视神经扎断后视网膜节细胞轴突再生的作用，两者有协同作用，各组再生的RGCs大小无明显差别。

Objective： To investigate the effects of cholera toxin （CTx） and pregnancy on promoting the axon regeneration of retinal ganglion cells （RGCs） in hamster retina. Methods： In day 3 after golden hamster mating, optic nerve （ON） microcrushed, CTx was injected intravitrously. The rats were separated into a regenerating control group （injuried group and inj uried＋ PBS group） and an experiment group （injuried＋CTx group, pregnancy-c injuried group, pregnancy＋ injuried＋ CTx group）. The rats in each group were allowed to survive for 3 weeks. The regenerating RGCs were labeled retrogradely with fluorogold, and changes in number of regenerating RGCs in each retina were observed under a fluorescence microscope. The circumference of regenerating RGCs in each experimental group was compared. Results： The mean numbers of regenerating RC-Cs in the injuried＋CTx group, pregnancy＋injuried group and pregnancy＋injuried＋CTx group were increased and sig nificantly higher than those in the injuried group and injuried＋PBS group. The mean numbers of regenerating RGCs in the pregnancy＋injuried＋CTx group were increased and significantly higher than those in the injuried＋CTx group and pregnancy＋injuried group. Conelusion： Our results indicate that both pregnancy and injection of CTx intravitrously could enhance the axon regeneration of the microcrushed RGCs significantly. These 2 factors have synergistic effect on RGCs regeneration. There is no significant difference in the size of regenerating RGCs in each experimental group.