Changes in spontaneous unit activity in lumbar spinal cord after reversible aortic occlusion in the rat

Lumbar dorsal horn neuronal multiunit activity was recorded in the halothane anesthetized rat before, during, and after a 30 min interval of spinal cord ischemia induced by inflation of a balloon catheter inserted through the femoral artery. After initiation of ischemia, there was typically a brief burst of neuronal activity, followed by electrical silence. During reperfusion, there was a progressive increase in discharge activity over the ensuing 30 min. Spontaneous activity was significantly increased, as measured by the number of discriminable cells and frequency of discharges. Post-ischemic hyperactivity reached maximal values typically after 60-90 min of reperfusion. The character and time course of recorded activity are consistent with the behavioral sequelae of transient spinal ischemia.