孤儿核受体1在大鼠视网膜发育过程中的表达

Expression patterns of NGFIB-β during rat retina development

目的：观察孤儿核受体1（NGFIB-13）在大鼠视网膜无长突细胞发育过程中蛋白表达的动态变化及与增殖细胞核抗原（PCNA）、突触融合蛋白、酪氨酸羟化酶（TH）的相关关系，探讨NGFIB-fl在视网膜发育过程中的表达意义。方法：采用石蜡包埋组织切片，免疫组织化学及免疫荧光双重显色。结果：NGFIB-13在视网膜发育过程中的表达呈现显著的动态变化，NGFIB-13从胚胎18d开始在大鼠视网膜组织出现少量表达，阳性表达主要在内核层内缘，随着发育的进行，阳性细胞数目明显增多，生后3～7d达到高峰，之后随着细胞的成熟，阳性表达又逐渐减少，成熟的视网膜组织内仅见少量阳性细胞，与PCNA的对比观察显示，两者表达在不同的部位和不同的细胞中，NGFIB-β主要表达在已分化的细胞中，在增殖细胞中不表达；NGFIB-β和视网膜无长突细胞特异性标记物syntaxin-1的免疫组织化学双重显色显示NGFIB-β阳性细胞为无长突细胞；NGFIB-β与TH的免疫组织化学双重标记显示两蛋白共表达在同一细胞中，但众多的NGFIB-β阳性细胞不表达TH。结论：NGFIB-β在大鼠视网膜多巴胺能无长突细胞及非多巴胺能无长突细胞从幼稚到成熟的分化过程中有重要调控作用．

Objective： NGFIB-β is a member of the nuclear receptor superfamily, and is involved in regulating the differentiation, migration and maturation of mesencephalic dopaminergie neurons. The present study was designed to observe NGFIB-β-protein expression patterns during rat retina development and the correlation with proliferating cell nuclear antigen （PCNA）, syntaxin-1 and tyrosine hydroxylase （TH）. Methods： Immunohistochemical double staining and fluorescence double staining was used. Results： The results revealed that dramatic and dynamic changed in NGFIB-β protein expression during retinal development. NGFIB-β-positive cells appeared in small quantities at embryonic day 18, and their number then increased markedly during development. The peak occurred at postnatal day 3-7. As maturation continued, the number of positive cells gradually decreased. Comparative observation of NGFIB-β and PCNA showed that NGFIB-β was confined to differentiated and migrating immature cells, and that it was not present in proliferating cells. NGFIB-β-positive cells, identified by comparative observation of NGFIB-β and syntaxin-1, were amacrine cells. In addition, the NGFIB-β and tyrosine hydroxylase coexisted in the same cells, but most cells with NGFIB-β expression did not express tyrosine hydroxylase. Conclusion： These results suggest that NGFIB-β may play a regulatory role in the differentiation and maturation of both dopaminergic and non-dopaminergic amacrine cells in the rat retina.