Brn-3a标记大鼠视网膜神经节细胞的实验研究

An Experimental Study on Brn-3a as a Marker of Retinal Ganglion Cells

目的对比Thy-1.1标记大鼠视网膜神经节细胞(RGCs)的方法,评估Brn-3a是否可作为一种可靠的内源性标记物,标记并计数大鼠RGCs。方法 20只SD大鼠,随机选取大鼠一眼为Thy-1.1组,另一眼作为Brn-3a组,常规H-E染色镜下观察RGCs的形态,运用免疫组织化学法检测Brn-3a与Thy-1.1的表达情况,每只眼球取1张切片,在每张待测视网膜切片上,以视网膜后极部中点为起点,至近角膜缘视网膜止点处,将视网膜分为3等份,即中央区、中间区及周边区,每个区域视网膜随机取5个高倍视野,分别计数Thy-1.1、Brn-3a阳性细胞均数。结果光镜下正常大鼠的视网膜从内向外可见3个细胞核层,依次为神经节细胞层(GCL)、内核层(INL)、外核层(ONL)。GCL的细胞呈单层排列,较为整齐,胞核清楚,数目相对较少,INL和ONL呈多层排列,且细胞排列紧密,数目相对较多。2种标记物染色都仅仅存在于视网膜的GCL,但在大鼠RGCs中分布呈明显差异:Brn-3a主要在胞核中着色,Thy-1.1主要在胞质中着色;运用此2种标记物标记计数RGCs,各个相同区域内Thy-1.1和Brn-3a阳性细胞计数比较,差别均无统计学意义(P>0.05)。Thy-1.1组和Brn-3a组中央区、中间区和周边区两两比较,差别均有统计学意义(P<0.01)。结论在大鼠视网膜中,Brn-3a可以作为一种比较可靠的内源性标记物,标记并计数大鼠RGCs。

Objective To identify Brn-3a is a reliable endogenous marker of RGCs by contrast with Thy-1.1 expression of the characteristics and differences count in rats.Methods 20 health adult SD rats were divided into two groups,one eye was selected randomly for group of Thy-1.1,at the other as group of Brn-3a in the same rat.Morphological structure was investigated by haematotoxylin-eosine staining of retinal paraffin section respectively.Expression of Brn-3a and Thy 1.1 was measured by immunohistochemical method.RGCs were counted by immunolabelled cells.Results There are ganglion cell layer（GCL）,inner nuclear layer（INL） and outer nuclear layer（ONL） in retina of rat.GCL was monolay er,alignment rarefaction.Brn-3a＋ cells were only present in the GCL and showed a spatial distribution comparable to that of Thy 1.1＋ cells：the Brn-3a signal was located in the nuclei,and the Thy-1.1 signal was major in the cytoplasm.There was no significant difference between the numbers of RCGs by labeling of these two markers in the same area.There was a significant difference among in the numbers of RCGs by labeling of these two markers in the different area.Conclusion Brn-3a can be used as a reliable marker to identify and quantify RGCs.