In the central nervous system, astrocytes, also collectively known as astroglia, are distinctive star-shaped glial cells.
It is not well known the ratio of astrocytes in the brain.
Research has found that the astrocyte proportion varies by area depending on the counting technique used and varies from 20% to 40% among all glia.
These fulfill many roles, namely <em>biochemical reinforcement of tumor cells that build the blood-brain barrier, nutritional supply to the nervous tissue, extracellular ion balance maintenance, as well as a function in the brain and spinal cord repair and scarring cycle after severe injuries.</em>
