Catalani Elisabetta, Tomassini Silvia, Dal Monte Massimo, Bosco Luigi, Casini Giovanni
Dipartimento di Scienze Ambientali, Università della Tuscia, Largo dell'Università snc, Blocco D, 01100, Viterbo, Italy.
Cell Tissue Res. 2009 Jun;336(3):423-38. doi: 10.1007/s00441-009-0787-9. Epub 2009 May 1.
Fibroblast growth factors (FGFs) exert basic functions both during embryonic development and in the adult. The expression of FGFs and their receptors has been reported in mammalian retinas, although information on the organization of the FGF system is still incomplete. Here, we report a detailed double-label immunohistochemical investigation of the localization patterns of FGF1 and its receptors FGFR1 and FGFR2 in adult and early postnatal mouse retinas. In adult retinas, FGF1 is localized to ganglion cells, horizontal cells, and photoreceptor inner and outer segments. FGFR1 is found in ganglion cells and Müller cells, whereas FGFR2 is primarily located in ganglion cells, the nuclei of Müller cells, and glycine-containing amacrine cells. During postnatal development, the patterns of FGF1, FGFR1, and FGFR2 immunostaining are similar to those in the adult, although transient FGF1-expressing cells have been detected in the proximal inner nuclear layer before eye opening. These patterns are consistent with a major involvement of FGF1, FGFR1, and FGFR2 in ganglion cell maturation (during development) and survival (in the adult). Moreover, FGF1 may affect amacrine cell development, whereas Müller cells appear to be regulated via both FGFR1 and FGFR2 throughout postnatal life. In immature retinas, large numbers of amacrine cells, including those containing calbindin and glycine, display both FGF1 and FGFR2 immunoreactivities in their nuclei, suggesting an action of FGF1 on FGFR2 leading to the maturation of these amacrine cells during a restricted period of postnatal development.
成纤维细胞生长因子（FGFs）在胚胎发育和成年期均发挥着基本功能。尽管关于FGF系统组织的信息仍不完整，但已有报道称FGFs及其受体在哺乳动物视网膜中表达。在此，我们报告了一项详细的双标免疫组织化学研究，该研究针对成年和出生后早期小鼠视网膜中FGF1及其受体FGFR1和FGFR2的定位模式展开。在成年视网膜中，FGF1定位于神经节细胞、水平细胞以及光感受器的内节和外节。FGFR1存在于神经节细胞和Müller细胞中，而FGFR2主要位于神经节细胞、Müller细胞的细胞核以及含甘氨酸的无长突细胞中。在出生后发育过程中，FGF1、FGFR1和FGFR2的免疫染色模式与成年期相似，尽管在睁眼之前，在近端内核层中检测到了短暂表达FGF1的细胞。这些模式与FGF1、FGFR1和FGFR2在神经节细胞成熟（发育过程中）和存活（成年期）中的主要作用一致。此外，FGF1可能影响无长突细胞的发育，而Müller细胞在出生后的整个生命过程中似乎受到FGFR1和FGFR2的双重调节。在未成熟的视网膜中，大量无长突细胞，包括那些含有钙结合蛋白和甘氨酸的细胞，在其细胞核中同时显示FGF1和FGFR2免疫反应性，这表明FGF1对FGFR2有作用，导致这些无长突细胞在出生后发育的特定时期成熟。
