Glial activity during axonal regrowth following cryogenic injury of rat spinal cord

The cryogenic model of spinal cord injury is associated with regrowth of axons through a zone of injury which is composed of a complex matrix of intact blood vessels, cells and extracellular materials. We have used this, therefore, as a means for studying the relationship between these cellular components, particularly the astrocytes, and the regrowing axons. For the time period of 60 days following injury we have found that, from an undifferentiated group of cells which appears early, there develops a population of astrocytes which is associated with the restoration of neural structure, including the return of axons, to the damaged area. We interpret these associations to be supportive through direct axonal interactions and indirect environmental contributions.