Radial glial cell and OPCs can be generated from radial glial cells "in vitro", more evidence is yet needed to conclude whether this process also occurs in the developing brain. Recently, radial glia that exclusively generate upper-layer cortical neurons have also been discovered. Since upper cortical layers have expanded greatly in recent evolution, and are associated with higher-level information processing and thinking, radial glia have been implicated as important mediators of brain evolution. The best characterized and first widely accepted function of radial glia is their role as scaffolds for neuronal migration in the cerebral and cerebellar cortexes. This role can be easily
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