Chiba C
University of Tsukuba, Institute of Biological Sciences, Tsukuba, Ibaraki 305, Japan.
Brain Res. 1998 Feb 23;785(1):171-7. doi: 10.1016/s0006-8993(97)01427-3.
The appearance of endogenous glutamate during retinal regeneration in the newt was examined by immunohistochemistry. Glutamate-like immunoreactivity (Glu-LI) first appeared in prospective ganglion cells along the vitreal margin of retinas that were about six cells thick, in prospective photoreceptors immediately before segregation of retinal plexiform layers and then in prospective bipolar cells immediately after the initial appearance of thin plexiform layers. In retinas nearing complete regeneration, Müller cells showed immunoreactivity. The appearance of glutamatergic phenotypes during retinal regeneration seemed to follow the order of cell differentiation [T. Saito, Y. Kaneko, F. Maruo, M. Niino, Y. Sakaki, Study of the regenerating newt retina by electrophysiology and immunohistochemistry (bipolar- and cone-specific antigen localization), J. Exp. Zool. 270 (1994) 491-500]. However, changes in the amount of endogenous glutamate during retinal regeneration were more complex. On the one hand, Glu-LI at the prospective ganglion cell layer temporarily increased during the initial period of segregation of the inner plexiform layer. On the other hand, immunoreactivity in the photoreceptor layer declined during segregation of the outer plexiform layer. The transient expression of immunoreactivity may represent a function of glutamate in events such as cell survival or neurite extension during retinal regeneration.
通过免疫组织化学方法检测了蝾螈视网膜再生过程中内源性谷氨酸的出现情况。谷氨酸样免疫反应性（Glu-LI）首先出现在约六层细胞厚的视网膜玻璃体边缘的前体神经节细胞中，在视网膜神经丛状层分离前的前体光感受器中，然后在薄的神经丛状层最初出现后的前体双极细胞中。在接近完全再生的视网膜中，穆勒细胞显示出免疫反应性。视网膜再生过程中谷氨酸能表型的出现似乎遵循细胞分化的顺序[T. 斋藤、Y. 金子、F. 丸尾、M. 新野、Y. 坂木，用电生理学和免疫组织化学方法研究蝾螈再生视网膜（双极细胞和视锥细胞特异性抗原定位），《实验动物学杂志》270（1994）491 - 500]。然而，视网膜再生过程中内源性谷氨酸含量的变化更为复杂。一方面，在内侧神经丛状层分离初期，前体神经节细胞层的Glu-LI暂时增加。另一方面，在外侧神经丛状层分离过程中，光感受器层的免疫反应性下降。免疫反应性的短暂表达可能代表了谷氨酸在视网膜再生过程中的细胞存活或神经突延伸等事件中的作用。
