Reducing postischemic paraplegia using conjugated superoxide dismutase.
Paraplegia after thoracic aortic aneurysm repair has an incidence of 2.2% to 24%. Oxygen-derived free radicals after reperfusion of an ischemic spinal cord may be partly responsible for neuronal destruction. We studied the effects of polyethylene glycol-conjugated superoxide dismutase (PEG-SOD), a free radical scavenger, as a way of increasing spinal cord tolerance to ischemia. Thirty rabbits underwent 40 minutes of aortic occlusion (a known model of paraplegia). Ten of these animals received 25,000 U/kg of PEG-SOD 24 hours before aortic occlusion and two additional doses of 10,000 U/kg, one before and one subsequent to spinal ischemia. Ten animals received superoxide dismutase in the same dosages as those receiving PEG-SOD. Ten control animals received placebo. All animals were studied for 96 hours, at which time a final neurological examination was performed and the results were recorded. Of the 10 animals treated with PEG-SOD, 2 were completely paralyzed whereas 8 had less (7) or no (1) neurological impairment. Eight of the 10 control animals and 9 of the 10 animals receiving superoxide dismutase were completely paralyzed. None of the control animals or animals receiving superoxide dismutase had a normal neurological examination (p less than or equal to 0.05). Treatment with PEG-SOD before and during occlusion increased the rabbit spinal cord tolerance to a 40-minute ischemic insult. Scavenging free radicals may lessen experimental spinal cord injury.
Agee
J M
JM
Department of Surgery, University of Virginia Health Sciences Center, Charlottesville.
Flanagan
T
T
Blackbourne
L H
LH
Kron
I L
IL
Tribble
C G
CG
D000818:Animals; D001014:Aortic Aneurysm / Q000601:surgery; D001794:Blood Pressure / Q000187:drug effects; D006339:Heart Rate / Q000187:drug effects; D007511:Ischemia / Q000150:complications / Q000503:physiopathology*; D008297:Male; D010264:Paraplegia / Q000209:etiology / Q000517:prevention & control*; D011092:Polyethylene Glycols; D011183:Postoperative Complications; D011817:Rabbits; D013116:Spinal Cord / Q000098:blood supply*; D013482:Superoxide Dismutase / Q000494:pharmacology*
D011092:Polyethylene Glycols; D013482:Superoxide Dismutase