Takeda H, Tomita M, Tanahashi N, Kobari M, Yokoyama M, Takao M, Ito D, Fukuuchi Y
Department of Neurology, School of Medicine, Keio University, Tokyo, Japan.
Neurosci Lett. 1998 Jan 2;240(1):5-8. doi: 10.1016/s0304-3940(97)00917-8.
Microglia are considered to serve as a guardian of the brain. In achieving this task, they have been observed to transform into a reactive form and then an ameboid form. Several substances are implicated in the control of such behavior. We examined the effect of hydrogen peroxide on cultured microglia of ameboid form obtained from the fetal rat brain employing video-enhanced contrast-differential interference contrast microscopy. Microglia harvested from the culture bottle were observed to float in a spherical shape with abundant filopodia on the surface. However, on coming into contact with the glass surface of a cover slip, they immediately transformed into an ameboid form. The microglia spread themselves out, surrounded by thin transparent lammellipodia, which would not be clearly observable by either light microscopy or electron microscopy. In a concentration-dependent fashion, 10(-3)-10(-1) M hydrogen peroxide solution enhanced the ruffling process of the lamellipodia and formation of vesicles (phagosomes), which displayed a typical phagocytotic form. It is concluded that an increase in free radicals in ischemic tissue tends to facilitate the phagocytosis of ameboid microglia as macrophages.
小胶质细胞被认为是大脑的守护者。在完成这项任务的过程中，人们观察到它们会转变为反应性形式，然后再转变为阿米巴样形态。有几种物质参与了对这种行为的控制。我们使用视频增强对比度-微分干涉对比显微镜，研究了过氧化氢对从胎鼠大脑获得的阿米巴样形态的培养小胶质细胞的影响。从培养瓶中收获的小胶质细胞呈球形漂浮，表面有丰富的丝状伪足。然而，当它们接触到盖玻片的玻璃表面时，会立即转变为阿米巴样形态。小胶质细胞展开，周围环绕着薄的透明片状伪足，而光学显微镜或电子显微镜都无法清晰观察到这些伪足。以浓度依赖的方式，10(-3)-10(-1)M的过氧化氢溶液增强了片状伪足的褶皱过程和囊泡（吞噬体）的形成，这些囊泡呈现出典型的吞噬形式。可以得出结论，缺血组织中自由基的增加倾向于促进阿米巴样小胶质细胞作为巨噬细胞的吞噬作用。
