Neuroprotective effect of regional carnitine on spinal cord ischemia-reperfusion injury

Objective: The purpose of this study was to investigate the effect of regio nal infusion of carnitine on spinal cord ischemia-reperfusion (IR) in rabbi ts. Methods: The 36 rabbits were divided into four equal groups, group I (s ham operated, no I-R injury), group II (control, only IR), group III (I-R intraaortic lactated Ringer's, LR, during aortic occlusion), group IV (I-R + LR plus 100 mg/kg carnitine). Spinal cord ischemia was induced by clampi ng the aorta both below the left renal artery and above the aortic bifurcat ion. The spinal cord function of all animals was assessed clinically 24 h a fter aortic declamping. Spinal cord samples were taken to measure the level s of tissue malondialdehyde (MDA) and to evaluate the histopathological cha nges. Results: We found significant increases in the levels of MDA in group s II and III compared with group I (P < 0.01), and elevation of MDA in grou p IV was insignificant. In group II, all animals (100%) were paraplegic wit h Tarlov's score of 0 and in group III, eight animals (88%) were paraplegic with Tarlov's score of 0 or 1. None of the animals (0%) from group IV was paraplegic. Histologic examination of spinal cords from group IV animals re vealed that the appearance of the spinal cord was relatively preserved, whe reas spinal cords from groups II and III had evidence of acute neuronal inj ury. Conclusion: The results suggest that regional infusion of carnitine du ring aortic clamping reduces spinal cord injury and prevents neurologic dam age in rabbit spinal cord I-R model. (C) 2001 Elsevier Science B.V. All rig hts reserved.