Tags: Anatomical Structure.
Microglia are a type of glial cell that are the resident macrophages of the brain and spinal cord and thus act as the first and main form of active immune defense in the central nervous system (CNS).Microglia constitute 10-15% of the total glial cell population within the brain. Microglia (and astrocytes) are distributed in large non-overlapping regions throughout the brain and spinal cord.Microglia are constantly scavenging the CNS for plaques damaged neurons and infectious agents.