<Tr> <Td> PNS </Td> <Td> Enteric glial cells </Td> <Td> <P> Are found in the intrinsic ganglia of the digestive system . They are thought to have many roles in the enteric system, some related to homeostasis and muscular digestive processes . </P> </Td> </Tr> <P> Are found in the intrinsic ganglia of the digestive system . They are thought to have many roles in the enteric system, some related to homeostasis and muscular digestive processes . </P> <P> Microglia are specialized macrophages capable of phagocytosis that protect neurons of the central nervous system . They are derived from the earliest wave of mononuclear cells that originate in yolk sac blood islands early in development, and colonize the brain shortly after the neural precursors begin to differentiate . </P> <P> These cells are found in all regions of the brain and spinal cord . Microglial cells are small relative to macroglial cells, with changing shapes and oblong nuclei . They are mobile within the brain and multiply when the brain is damaged . In the healthy central nervous system, microglia processes constantly sample all aspects of their environment (neurons, macroglia and blood vessels). In a healthy brain, microglia direct the immune response to brain damage and play an important role in the inflammation that accompanies the damage . Many diseases and disorders are associated with deficient microglia, such as, Alzheimer's disease, Parkinson's disease, and ALS . </P>

Neuroglia that support neurons and blood vessels are