The main functions of glial cells

Through research, biologists have divided cells into several types, each of which has unique functions. Glial cells are one of the main cells distributed in neurons. The main function of glial cells is to protect, repair and nourish neurons, especially in the aspects of repair and transport of nutrients. Please read the following content for details.

1. Glia

Neuroglia is the abbreviation of glial cells. It is another major type of cell in the nervous tissue besides neurons, distributed between neurons to form a mesh-like scaffold. Their number is 10-50 times greater than that of neurons. Glial cells also have multiple processes, but there is no distinction between dendrites and axons. The cytoplasm does not contain Nissl bodies and neurofibrils, and has no function of sensing stimuli and conducting impulses. But they are involved in the activities of neurons and have multiple functions for neurons, including support, protection, nutrition, myelination and repair.

2. Related functions

(1) Supportive role: Since glial cells extensively and tightly surround nerve cells, they play a supporting role. In addition, during the development of the cerebral cortex and cerebellar cortex of humans and monkeys, neurons migrate along the direction of the glial cell processes to the site where they will later "settle". Therefore, glial cells seem to provide a certain basic scaffold for the development and organization of nerve cells.

(2) Isolation and insulation: glial cells may have the function of limiting the diffusion of K and neurotransmitters.

(3) Uptake of chemical substances. The dorsal root ganglia, spinal cord, autonomic ganglia of mammals and the glial cells at the neuromuscular junctions of crustaceans can take up GABA.

(4) Secretory function. Glial cells have secretory function. For example, in chronically denervated skeletal muscle, Schwann cells occupy the position of nerve endings, which can secrete acetylcholine and induce microendplate potentials.

(5) Repair and regeneration: the glial cells of adult animals still retain the ability to grow and divide. When nerve cells disappear due to damage or aging, their gaps are filled by dividing and proliferating glial cells, which play a role in repair and regeneration. During peripheral nerve regeneration, axons grow along the paths opened up by Schwann cells.

(6) Nutritional transport: some end feet of glial cells are attached to the capillary walls, while other end feet are in contact with neurons, which may play a role in transporting nutrients.