The pathological lesion in spinal injury is usually more severe in the central gray matter and spreads centrifugally to surrounding white matter. Opiate antagonists, naloxone, by blocking the pathophysiologic effect of endorphins, should increase both mean arterial pressure and spinal cord blood flow and limit neurologic injury. Naloxone produce increase of lateral column blood flow and ameliorate the central gray matter ischemia. We have investigated to thoracic cord confusion. The spinal cord of naloxone-treated cats has less tissue damage than would be observed in time-matched standards.