ABSTRACT
Neuroglia comprise the main cellular homeostatic element of the central nervous system. Glial cells are classically divided into macroglia (astrocytes, oligodendrocytes, and NG2 cells, all of ectodermal origin) and microglia (the resident Central Nervous System (CNS) macrophages of myeloid origin). The functions of these cells are many (for review see Iadecola and Nedergaard 2007; Magistretti 2006; Nedergaard et al. 2003; Newman et al. 1984; Simard and Nedergaard 2004; Zonta et al. 2003; Kettenmann and Verkhratsky 2008; Verkhratsky 2009, 2010; Verkhratsky and Kirchhoff 2007); however, all of them are speci¡cally involved in control of brain homeostasis at various levels, from control over ion and neurotransmitter concentrations in brain interstitium to regulation of morphological plasticity of neural networks, including synapto-and neurogenesis.
