Glial scar brain and spinal cord. FGF2 has also been shown to increase astrocyte proliferation "in vitro". Ciliary neurotrophic factor (CNTF) is a cytosolic protein that is not secreted. CNTF has been shown to promote the survival of neuronal cultures "in vitro", and it can also act as a differentiator and trophic factor on glial cells. Further, CNTF has been previously shown to affect the differentiation of glial precursor cells "in vitro"; however, the influence of CNTF in the "in vivo" setting has only recently been determined. Winter "et al." used CNTF over-expressing transgenic mice as well as wildtype controls that had
Satellite glial cell grooves of the sheath, allowing for possible exchange of materials between the cells. In the sympathetic ganglia, satellite glial cells are one of three main types of cells, the other two being the sympathetic ganglion neurons and small intensely fluorescent (SIF) cells. SIF cells of sympathetic ganglia are separated into groups, each of which is surrounded by an SGC sheath. The SGCs of the sympathetic ganglia come from the neural crest and do not proliferate during embryonic development until the neurons are present and mature, indicating that the neurons signal the division and maturation of the SGCs. The SGCs of