Sam Schmidt Paralysis Foundation a cell body, which houses the nucleus. Axons and dendrites form extensions from the cell body. Glial cells are "nerve-helper" cells that provide structural support, nourishment and protection for neurons. Astrocytes, a kind of glial cell, are the primary support cells of the brain and spinal cord. They make and secrete proteins called neurotrophic factors, which assist in the maintenance of nerve cells in the central nervous system. They also break down and remove proteins or chemicals that might be harmful to neurons (for example, glutamate, a neurotransmitter that in excess causes cells to become overexcited and die by a
Satellite glial cell found in different cells. Although SGCs express glial fibrillary acidic protein (GFAP) and different S-100 proteins, the most useful marker available today for SGC identification is glutamine synthetase (GS). The levels of GS are relatively low at rest, but they greatly increase if the neuron undergoes axonal damage. Furthermore, SGCs also possess mechanisms to release cytokines, adenosine triphosphate (ATP), and other chemical messengers. Research is currently ongoing in determining the physiological role of satellite glial cells. Current theories suggest that SGCs have a significant role in controlling the microenvironment of the sympathetic ganglia. This is based on the observation that