Protection of hyperbaric oxygen preconditioning for acute ischemic spinal cord re-perfusion injury in rabbits.

Objective:To investigate the mechanism of hyperbaric oxygen preconditioning for acute ischemic spinal cord re-perfu-sion injury in rabbits.Methods:20 male New Zealand white rabbits were randomly allocated to 2 groups(10 in each group):animals in control group received room air and normal ambient pressure;animals in HBO group received HBO pretreatment.At 48 h after reperfu-sion,the neurologic status was scored by the Tarlov criteria.All the animals were sacrificed at 48 h after reperfusion and their spinal cords(L5-7)were removed to determine the activeness of antioxidase(SOD,CATand GSH-px)and the level of MAD.Results:The neuro-logic function scores in HBO group were higher than that in control groups at 4,12,24,48 h after reperfusion(P0.05).The activeness of antioxidase(SOD,CATand GSH-px) in HBO group were higher than that in control group and the level of MAD was lower than that in control group at 48h after reperfusion(P0.05).A positive correlation was found between the neurologic function scores and the active-ness of antioxidas in spinal cord(r=0.82,0.65,0.54,P0.05).A negative correlation was found between the neurologic function scores and the level of MAD in spinal cord(r=-0.69,P0.05).Conclusion:Thenmechanism of hyperbaric oxygen preconditioning-induced ischemic to lerance in the spinal cord of rabbits might be related to increasing of the activeness of antioxidas and the production of oxygen free rad-icals by HBO pret reatment.