Role of free radical scavenger in protection of spinal cord during ischemia

Previous work in our laboratory established an experimental model for the production of paraplegia in the anesthetized normothermic adult mongrel dog. The current study involves 24 animals divided into two equal groups: Group 1 served as control, and Group 2 received treatment with scavenger agent. Vascular occlusive clamps were placed on the thoracic aorta proximal to the left subclavian artery, on the left subclavian artery at its origin, and on the distal thoracic aorta at the diaphragm for 30 minutes. In Group 1,200 ml of normal saline solution (37 degrees C) was perfused into the occluded aortic segment at the rate of 0.33 ml per kilogram of body weight per minute. In Group 2, 90% dimethyl sulfoxide (DMSO) in a dose of 0.1 gm/kg in normal saline solution (37 degrees C) for a total volume of 200 ml, was likewise injected into the occluded aortic segment at the same infusion rate. Animals were observed for evidence of paresis in the postoperative period. Microscopic analysis revealed evidence of ischemic myelopathy in the control group but none in the treated group. Under the conditions of this experiment, we conclude that the scavenger agent DMSO has a highly protective effect on the spinal cord during ischemic insult.