Functional roles of microglia in the central nervous system.

Microglia, a type of perineuronal glial cells in the central nervous system, have been suggested to play various important roles in normal and pathologic brains. In this article, first, we described the association or roles of activated microglia in injury and various brain diseases, and subsequently, summarized microglia-derived physiologically active molecules which will affect the neuronal survival and neuronal growth, and glial function, and finally, discussed the molecular mechanism of microglial activation.