Microscopic analysis of early histopathological spinal cord alterations following trauma in normal and catecholamine-depleted cats

The progressive histopathological sequence over the first 3 hr after a 400 g-cm blunt injury to the spinal cord of catecholamine (CA)-intact and CA-depleted cats is described. Norepinephrine levels were measured in all animals. The experiments were designed to determine the role of CA in progressive hemorrhagic necrosis of the spinal cord by removing CA from one group of animals prior to trauma. A second group of CA-intact animals was subjected to identical experimentally-induced trauma. Upon analysis of the histopathological changes, it appears that the sequential nature of the development of hemorrhagic necrosis is both qualitatively and quantitatively similar in both experimental groups. The general conclusion is drawn that catecholamines in greater than normal amounts are present at the lesion site after trauma, but these catecholamines are probably not involved in the process of central hemorrhagic necrosis.