增龄大鼠视网膜老化过程中各层细胞数目变化

Change of number of cells in each layer of retina of aging rats

目的动态观察大鼠视网膜神经节细胞层、内核层、外核层细胞数目随年龄增长的变化趋势。方法雄性SD大鼠36只,按1个月龄、3个月龄、6个月龄、12个月龄、18个月龄、24个月龄分为6组,采用眼球视网膜组织病理切片、HE染色,分层计数各层视网膜细胞数目。结果1个月龄、3个月龄、6个月龄、12个月龄、18个月龄、24个月龄组大鼠视网膜神经节细胞层细胞平均数目分别为6.83±1.47、6.67±1.63、6.27±1.17、5.73±1.51、5.40±1.79、5.00±1.41;各月龄组大鼠视网膜内核层细胞数目平均分别为38.33±3.50、37.17±7.55、37.17±3.31、36.17±7.70、37.83±4.11、35.50±4.51;各月龄组大鼠视网膜外核层细胞平均数目分别为72.50±10.19、71.17±7.65、67.00±8.07、66.83±10.50、63.67±8.12、61.83±7.50。1个月龄组及24个月龄组大鼠视网膜神经节细胞层和外核层细胞数目比较差异均有统计学意义(P<0.05),1个月龄及24个月龄外核层细胞数目比较差异也有统计学意义(P<0.05),其余各层视网膜各组细胞数目比较差异均无统计学意义(P>0.05)。相关分析表明神经节细胞层细胞数目及外核层细胞数目与月龄呈负相关(R=-0.673,-0.589;P<0.05),内核层细胞数目与月龄无相关关系(R=-0.120;P>0.05)。结论大鼠视网膜神经节细胞层细胞数目及外核层细胞数目均随年龄增长呈下降趋势,而内核层细胞数目随年龄增长无明显变化,提示视网膜组织在老化过程中细胞数目的减少主要发生在神经节细胞层及外核层。

Objective To investigate the change of the number of cells in each layer of the retina of aging rats. Methods Thirty-six Sprague Dawley （SD） rats were divided into six groups by age, including 1 month group, 3 months group, 6 months group, 12 months group, 18 months group, 2A months group,six rats in each group. Pathological section and hematoxylin and eosin （HE） staining were used to count cells in each layer of retina. Results In 1 month group, 3 months group, 6 months group, 12 months group, 18 months group,24 months group,the number of retinal ganglial cells （RGC） were 6.83 ± 1.47,6.67 ± 1.63,6.27 ± 1.17,5.73 ± 1.51,5.40 ± 1.79,5.00 ± 1.41 ,respectively;The number of inner nuclear layer cells were 38.33 ± 3.50,37.17 ± 7.55,37.17± 3.31, 36.17 ± 7.70,37.83 ± 4.11,35.50 ± 4.51, respectively; The number of outer nuclear layer cells were 72.50 ± 10.19,71.17 ± 7.65,67.00 ± 8.07,66.83 ± 10. 50,63. 67 ± 8.12, 61.83 ± 7.50 ,respectively. The number of RGC and outer nuclear layer cells were statistical different between 1 month group and 24 months group （P 〈 0.05）. The number of cells were not statistical different between other groups of each layer （P 〉 0.05 ）. The number of RGC and month＇ s age correlated inversely （ R = - 0. 673;P 〈 0.05 ）. The number of outer nuclear layer cells and month＇ s age correlated inversely（R = - 0.589; P 〈 0.05 ）. The number of inner nuclear layer cells and month＇s age was no correlation（R = -0. 120;P〉0.05）. Conclusion The number of RGC and outer nuclear layer cells decreased with aging, while the number of inner nuclear layer cells was not. This phenomenon indicates that the reduction of the number of cells mainly happens in RGC and outer nuclear layer in the aging process of retina.