Astroglial physiology

Astroglia are neural cells of ectodermal, neuroepithelial origin that provide for homeostasis and defence of the central nervous system. Astroglia include several cell types, including numerous types of astrocytes, radial glia, ependymocytes and, in higher primates, specialised interlaminar astrocytes and astrocytes with varicose projections. Astroglial cells are highly heterogeneous in morphological appearance and physiological properties; they express a multitude of receptors, channels and membrane transporters. This extended complement of signalling and homeostatic molecules underlies the remarkable adaptive plasticity of astroglial cells and enables the functional maintenance of the CNS in development and ageing. Astroglia are fully integrated into neural networks and control homeostasis of the CNS at all levels of organisation from molecular to the whole organ.