The Correlation Between Cx43 And BSCB In Improving Spinal Cord Ischemia Reperfusion Injury In Rabbits By Remote Ischemic Preconditioning

[Aims] To investigate the correlation between C x43 and BSCB in improving spinal cord ischemia reperfusion injury in rabbits by remote ischemic preconditioning.[Methods] Thirty-six Japanese white rabbits were randomly equally divided to 3 groups: sham-operation group(S ham);ischemia-reperfusion group(I/R);ischemia-reperfusion with remote ischemic preconditioning(I/R+R).Sham Group underwent a time matched sham procedure without intervention.I/R Group underwent a 40 min aortic occlusion followed by reperfusion.I/R+R Group underwent bilateral femoral artery occlusion(10 min ischemia/ 10 min reperfusion,2 cycles)one hour before I/R procedures.Sham Group and I/R Group separated the bilateral femoral artery without cross-clamping at the same time point.At 48 h after reperfusion,Tarlov criteria assessed the Hind-limb motor function,and the pathological changes of spinal cord was observed by histologic evaluation and Tunel stains.The permeability of the blood-spinal cord barrier was measured by the EB content of spinal cord.The expression of Connexin 43(Cx43),Tumor Necrosis Factor-?(TNF-?),Interleukin-1?(IL-1?),and matrix metalloproteinase-2/9(MMP-2/9)were detected by Western blot and RT-PCR.[Results] Remote ischemic preconditioning improved the neuromotor function and histopathologic destruction and alleviated EB extravasation at 48 h after spinal cord ischemia reperfusion injury.Besides,compared with I/R group,Remote ischemic preconditioning suppressed the increases of C x43,TNF-?,IL-1? and MMP-2/9 induced by spinal cord ischemia reperfusion injury in the I/R+R group(P<0.05).[Conclusion] Remote ischemic preconditioning stabilized the blood-spinal cord barrier integrity after spinal cord ischemia reperfusion injury in a rabbit model.This beneficial effect may be connected with suppressing the expression of Cx43,which subsequently down-regulated the expression of TNF-?,IL-1? and MMP-2/9.