Comparison of Naloxone and Thyrotropin-Releasing Hormone in the Treatment of Experimental Spinal Injury. Annual Report August 1, 1983 - September 30, 1984

摘要

Traumatic injuries to the central nervous system (CNS: including spinal cord and brain) cause neurologic impairment not only by directly interrupting neuronal pathways but by initiating a series of pathophysiologic changes which lead to progressive ischemic damage. We have provided evidence that the secondary ischemic changes resulting from experimental spinal trauma are potentially reversible and result, in part, from a reduction of spinal cord blood flow related to the release of endogenous opioids. Previously, we have shown that the opiate receptor antagonist naloxone improves both spinal cord and blood flow and neurological outcome following experimental traumatic spinal cord injury in the cat. Subsequently, we found that thyrotropin-releasing hormone (TRH), which acts in part as a physiologic antagonist of endogenous opioid systems, also significantly improves blood flow and neurological recovery after experimental spinal injury. During this contract we have compared the effects of TRH and naloxone against corticosteroids and saline-treated controls. Both naloxone and TRH provided significantly superior to either saline or high-dose corticosteroids in improving long-term, functional neurological recovery in the cat. Moreover, TRH proved significantly better than naloxone in this regard. TRH treatment significantly improved neurological recovery even when the drug was not administered until fully 24 h after traumatic injury.