The Expression Of Bax And Fas After Hind Limbs Eschemia-reperfusion Injury Of In Spinal Cord And Effects Of PGE₁

Ischemia-reperfusion injury(IRI) of limb was observed frequently in surgery,so to investigate the ischemia-reperfusion injury of limb is very significant. Ischemia-reperfusion injury of limb not only caused local injury,but also provoked injury of distant organs,such as lung,kidney and brain etc,even caused multiple organ dysfunction syndrome(MODS).The research of wang Fa indicated that these were changes of morphology and electrophysiology in nervus peripheralis.Spinal cord is critical system in dominanting limbs.The change of nervus peripheralis may cause spinal cord injury. The evidence suggested that ischemia-reperfusion can induce apoptosis in cells.Could the ischemia-reperfusion of limb(LIR) induce apoptosis in spinal cord neuron? This study was discussing the expression of apoptosis corrective genes in spinal cord after LIR,and protection of PGE1.The results would provid us some ideas in terms of LIR.Objective:We determined the expression of apoptosis corrective genes,including Bax and Fas,after hind limbs inschemia-reperfusion(LIR) in rat spinal cord, and effective of PGE1Method:The experiments were carried out on male SD rats in three groups.①Sham group(n=24);②I/R group (n=24);③Drug group (n=24).The limbs inchemia-reperfusion model was established in rats.In Drug group,the rats were intravenous injected PGE1 with dose of 5μg·Kg-1 before reperfusion 30 min.The histopathological changes of spinal cord were determined by HE staining, the expression of apoptosis associated protein,such as Bax and Fas were determined with immunohistochemistry,apoptotic cells were detected with TUNEL.Result:Compared with the sham group,the expression of Bax and Fas following LIR significantiy increased in I/R group and Drug group (P<0.01 or P<0.05), the Bax positive neurons peaked at 12h after LIR,the Fas positive neurons peaked at 24h, and decresed gradually with time following LIR. There were no significant apoptosis cells in sham group.Ischemia-reperfusion increased obviously apoptosis index of spinal cord(P<0.01 or P<0.05),while PGE1 attenuated significantly these changes(P<0.01 or P<0.05).Conclusion:①Apoptosis of spinal cord neuron participated in the injury induced by ischemia-reperfusion of hind limbs.②Ischemia-reperfusion can increase Bax and Fas.③PGE1 injecting 30 min before reperfusion has inhibitive effect on spinal cord apoptosis following ischemia-reperfusion of hind limbs in rats. PGE1 may protect sipnal cord by decreasing Bax and Fas. The results might suggest that the expression of Bax and Fas may play a vital role in regulating the neural apoptosis following LIR in rats, PGE1 can protect spinal cord after LIR.