Neuroglial cells are the supportive cells of nervous tissue. They outnumber neurons about 10 to 1. Like neurons, glial cells are composed of cell bodies and cell processes. (Note: Glial processes are visible only in special stained preparations, such as a Golgi stain.)
Three major types of neuroglial cells are recognized in the central nervous system:
(a) astrocytes -- provide structural & functional support for the CNS;
(b) oligodendroglia -- form myelin in the CNS, and
(c) microglia -- serve as a macrophage in the CNS.
Astrocytes:On glass slide 49 in your Histology slide box, cerebral cortex of dog (Golgi stain), search for astrocytes such as those illustrated below.
On glass slide 49 in your Histology slide box, cerebral cortex of dog (Golgi stain), search for ologodendrocytes such as those illustrated below.
On glass slide A-1 in your Neuroanatomy slide box, canine spinal cord, search the white matter for astrocyte and ologodendrocyte cell bodies as they appear in routine stains, illustrated below.
Microglia are difficult to find. Microglial cells have small elongate perikarya and short cell processes. They comprise only about 4% of the glial cell population under normal circumstances. An example of a microglial cell will be on demonstration in the laboratory.