| Part oneThe Temporal Profile of Astrocytes and JAK-STAT Signal Pathway after Spinal Ischemia and Reperfusion Injury in RabbitsObjective:To observe the evolution of astrocytes,GDNF,BDNF and JAK-STAT signal pathway after spinal cord ischemia-reperfusion(SCIR)injury in rabbits.Methods:Spinal cord ischemia was induced by means of balloon occlusion of the infrarenal aorta for 22 minutes in 54 male New Zealand white rabbits.We assigned rabbits to 9 groups(n=6 in each),one sham group,eight operation group.The operation process in the sham group was the same as the operation group except the ischemia reperfusion of the spinal cord.At Oh,1h,2h,3h,8h,24h,48h and 72h after reperfusion,animals were killed and the spinal cord was removed for histologic,immunohistochemical study and western blotting.Results:Normal neurons were decreased with the extension of reperfusion time.TUNEL-positive cells were increased at 8h and peaked at 24h after spinal cord injury.Levels of GFAP increased at 3h and reached a peak at 48h after reperfusion.GDNF was increased reaching two peaks after injury,the first peak was at 3h,the second was at 72h.BDNF level was increased and peaked at 24h after reperfusion.The expression of p-STAT3 showed a biphasic pattern which peaked at 1h and 48h in SCIR.GFAP,GDNF,BDNF,TUNEL-positive cells were rare and the level of p-STAT3 could be neglected in sham group.Conclusion:Spinal cord ischemia-reperfusion injury could induce the activation of astrocytes,the expression of GDNF,BDNF and the activation of JAK-STAT signal pathway.They showed different expression rules in this study.Part twoThe activation of microglia and the changes of inflammatory cytokine after spinal cord ischemia reperfusion in rabbitsObjective:To observe the activation of microglia cells,the expression rules of inflammatory cytokines such as IL-6,IL-10,and NF-κB after spinal cord ischemia-reperfusion(SCIR)injury in rabbits.Providing theoretical basis for postconditioning time.Methods:Spinal cord ischemia was induced by means of balloon occlusion of the infrarenal aorta for 22 minutes in 54 male New Zealand white rabbits.Rabbits were randomly divided into 9 group s(n=6 in each),one sham group,eight ischemia-reperfusion groups:C0、C1、C2、C3、C8、C24、C48、C72.At Oh,1h,2h,3h,8h,24h,48h and 72h after reperfusion,animals were killed and the ischemia spinal segments were removed for histologic,immunohistochemical study and western blotting test.Results:Normal neurons were decreased with the extension of reperfusion time.TUNEL-positive cells were increased at 8h and peaked at 24h after spinal cord injury.The level of Iba-1 was increased at 2h and reached a peak at 8h after reperfusion.NF-κB level was increased at 3h and peaked at 8h after reperfusion.IL-6 and IL-10 were increased to the peaks at 24h after injury.The expression of Iba-1,IL-6,IL-10,NF-κB were absolutely less as well as the number of TUNEL-positive cells in sham group.The expression levels of NF-κB,IL-6,IL-10 were all positive correlated with the Iba-1 expression.Conclusion:Spinal cord ischemia-reperfusion injury could induce the activation of microglia cells,and significant positive correlations were observed between the expression of Iba-1 and IL-6,IL-10,NF-κB,respectively.Giving post treatment before the microglia activation could reduce the neuronal injury. |
