Astrocytes: There are two main types of astrocytes. The first of them is known as the fibrous astrocyte. Fibrous astrocytes are astrocytes that are mainly found in the white matter of the nervous system. However, some can be found in the gray matter, such as in the thalamus of people. The second major kind is the protoplasmic astrocyte. Protoplasmic astrocytes are mainly found in the gray matter of the nervous system. Astrocytes have numerous functions. If our central nervous system were a city, then some astrocytes work in the public water department. That's because that department is responsible for ensuring that water gets to its citizens in an appropriate manner through the pipes. Well, the central nervous system has pipes of its own, blood vessels, and the astrocytes help regulate the flow of blood through these vessels.