The figure on the side shows the main cell types. Astrocytes Astrocytes are abundant in the brain, and help regulate the chemical milieu of the extracellular space.
Astrocytes can take up neurotransmitters, and even possess neurotransmitter receptors.
Astrocytes also proliferate in response to brain injury, and contribute significantly to the scarring process that appears to prevent reinnervation after stroke or spinal injuries. Microglia Another type of glia in the CNS, the microglia, are the immune cells of the brain. They respond in a similar fashion to macrophages peripherally, and possess complement proteins that may contribute to certain CNS disorders. See our Neuroinflammatory Programme for more information.