In vitro spinal cord trauma.

Fetal mouse spinal cord explants were harvested and allowed to grow in Maximow chambers. Normal appearing matured cultures were subjected to a brief episode of impact trauma by dropping the flat surface of 25 to 105 mg dressmaker's pins from a height of 10 cm directly onto the exposed surface of the culture. Light and electron microscopic studies at selected posttrauma intervals revealed discrete foci of necrosis preceded or accompanied by nerve fiber changes (granular axoplasm, vesicular myelin, pleomorphic spheroids) identical with those documented in spinal cord trauma in vivo. Although no inherent calcification was observed, calcium was added to some of the traumatized cultures and it was subsequently localized by pyroantimonate in the axoplasm; within mitochondria, adjacent to neurofilaments, and in the cytosol. The study indicates that the morphologic sequence of events of spinal cord trauma in vitro are similar to those observed in vivo, and that the latter may occur in the absence of vascular injury.