First of all, it should be noted that the nervous tissue is not a usual cluster of neurons, but a harmonious integration of interactions between neurons and glial cells that fill the free space. The parallel work of neurons coupled with the functionality of glial cells allows for full brain function. It is known that the number of such glial structures exceeds the number of neurons many times, and the imbalance between the two links has the potential to cause pathologies of the nervous system.
Due to the distinctive features of some glial cells, it was decided to divide them into different subtypes, including ependymal cells, oligodendrocytes and astrocytes, and microglia cells. The abundance of subspecies is justified not only by the form and size of cells but also by their functionality. In particular astrocytes have the star form expressed through a set of branches that deviate from a body of a cell in different directions. While some of the offshoots end up in neural contact, some of them are integrated into the blood system. The main functions of astrocytes include creating mechanical frame support for neurons, creating a hematoencephalic barrier, maintaining trace element concentrations, and participating in reparative processes after damage.
In contrast, oligodendrocytes are small oval-shaped cells with an abundance of fine short cells that are in the grey and white matter around the neurons. Among other issues, oligodendrocytes form myelin shells around long axons and long dendrites. In other words, the primary function of oligodendrocytes is to form an isolating layer for neurons. Microglial cells are much smaller, have an uneven star shape, and short spurs. The function of microglia is to protect neurons from inflammation and infection.
Finally, ependymocytes are cells that divide the ventricles of the brain and the central channel of the spinal cord by secreting cerebrospinal fluid. On the surface of the cells, which are prismatically shaped, there are cilium which, with their activity, promote the movement of cerebrospinal fluid. In addition, the ependymocytes participate in the metabolism of the CSF and the dissolution of substances in it.