Astrocytes are intimately involved in the formation and development of retinal vessels. Astrocyte dysfunction is a major cause of blood-retinal barrier injury and other retinal vascular diseases. In this study, the de...Astrocytes are intimately involved in the formation and development of retinal vessels. Astrocyte dysfunction is a major cause of blood-retinal barrier injury and other retinal vascular diseases. In this study, the development of the retinal vascular system and the formation of the blood-ret-inal barrier in mice were investigated using immunolfuorescence staining, gelatin-ink perfusion, and transmission electron microscopy. The results showed that the retinal vascular system of mice develops from the optic disc after birth, and radiates out gradually to cover the entire retina, taking the papilla optica as the center. First, the superifcial vasculature is formed on the inner retinal layer;then, the vasculature extends into the inner and outer edges of the retinal inner nuclear layer, forming the deep vasculature that is parallel to the superifcial vasculature. The blood-retinal barrier is mainly composed of endothelium, basal lamina and the end-feet of astrocytes, which become mature during mouse development. Initially, the naive endothelial cells were immature with few organelles and many microvilli. The basal lamina was uniform in thickness, and the glial end-feet surrounded the outer basal lamina incompletely. In the end, the blood-retinal barrier matures with smooth endothelia connected through tight junctions, rela-tively thin and even basal lamina, and relatively thin glial cell end-feet. These ifndings indicate that the development of the vasculature in the retina follows the rules of“center to periphery”and“superifcial layer to deep layers”. Its development and maturation are spatially and tempo-rally consistent with the functional performance of retinal neurons and photosensitivity. The blood-retinal barrier gradually becomes mature via the process of interactions between astro-cytes and blood vessel cells.展开更多
基金supported by the National Natural Science Foundation of China,No.30771140,31070952 and U1204311
文摘Astrocytes are intimately involved in the formation and development of retinal vessels. Astrocyte dysfunction is a major cause of blood-retinal barrier injury and other retinal vascular diseases. In this study, the development of the retinal vascular system and the formation of the blood-ret-inal barrier in mice were investigated using immunolfuorescence staining, gelatin-ink perfusion, and transmission electron microscopy. The results showed that the retinal vascular system of mice develops from the optic disc after birth, and radiates out gradually to cover the entire retina, taking the papilla optica as the center. First, the superifcial vasculature is formed on the inner retinal layer;then, the vasculature extends into the inner and outer edges of the retinal inner nuclear layer, forming the deep vasculature that is parallel to the superifcial vasculature. The blood-retinal barrier is mainly composed of endothelium, basal lamina and the end-feet of astrocytes, which become mature during mouse development. Initially, the naive endothelial cells were immature with few organelles and many microvilli. The basal lamina was uniform in thickness, and the glial end-feet surrounded the outer basal lamina incompletely. In the end, the blood-retinal barrier matures with smooth endothelia connected through tight junctions, rela-tively thin and even basal lamina, and relatively thin glial cell end-feet. These ifndings indicate that the development of the vasculature in the retina follows the rules of“center to periphery”and“superifcial layer to deep layers”. Its development and maturation are spatially and tempo-rally consistent with the functional performance of retinal neurons and photosensitivity. The blood-retinal barrier gradually becomes mature via the process of interactions between astro-cytes and blood vessel cells.