Liu Guo Jun, Nagarajah Rajini, Banati Richard B, Bennett Max R
The Neurobiology Laboratory, Brain and Mind Research Institute, University of Sydney, NSW, Australia.
Eur J Neurosci. 2009 Mar;29(6):1108-18. doi: 10.1111/j.1460-9568.2009.06659.x.
Microglia in the brain possess dynamic processes that continually sample the surrounding parenchyma and respond to local insults by rapidly converging on the site of an injury. One of the chemotaxic agents responsible for this response is ATP. Here we show that the transmitter glutamate is another such chemotaxic agent. Microglia exposed to glutamate increase their cell membrane ruffling and migrate to a source of glutamate in cell culture and in spinal cord slices. This chemotaxis is meditated by alpha-amino-3-hydroxy-5-methylisoxazole-4-propionic acid (AMPA) and metabotropic glutamate receptors on the microglia. Chemotaxis is dependent on redistribution of actin filaments in the cells and on tubulin following receptor activation. Thus glutamate, which is released at synapses as well as from damaged cells, can mediate rapid chemotaxic responses from microglial cells.
大脑中的小胶质细胞具有动态的突起，这些突起不断地对周围实质进行采样，并通过迅速聚集到损伤部位对局部损伤做出反应。负责这种反应的趋化因子之一是三磷酸腺苷（ATP）。在这里，我们表明神经递质谷氨酸是另一种这样的趋化因子。暴露于谷氨酸的小胶质细胞会增加其细胞膜褶皱，并在细胞培养物和脊髓切片中迁移到谷氨酸源。这种趋化作用由小胶质细胞上的α-氨基-3-羟基-5-甲基异恶唑-4-丙酸（AMPA）和代谢型谷氨酸受体介导。趋化作用取决于受体激活后细胞中肌动蛋白丝和微管蛋白的重新分布。因此，在突触以及受损细胞中释放的谷氨酸可以介导小胶质细胞的快速趋化反应。
