缺血预处理对肢体缺血/再灌注大鼠胃粘膜损伤的保护效应

THE PROTECT EFFECT OF ISCHEMIC PRECONDITIONING ON THE GASTRIC MUCOSAL INJURY FOLLOWING ISCHEMIA/REPERFUSION OF HIND LIMBS OF RATS

目的:观察肢体缺血再灌注(LI/R)对胃粘膜的损伤作用及缺血预处理对其影响,探讨胃粘膜损伤的机制及缺血预处理(IPC)的作用机理。方法:观察并测定肢体缺血4h再灌注4h后以及应用肢体缺血预处理干预后各组胃粘膜损伤指数,胃结合粘液量;检测胃粘膜中髓过氧化物酶(MPO)、超氧化物歧化酶(SOD)、丙二醛(MDA)、黄嘌呤氧化酶(XOD)含量的变化以及血浆中乳酸脱氢酶(LDH)的含量变化。结果:大鼠LI/R后胃粘膜损伤指数增加;胃结合粘液量较对照组显著下降;胃粘膜中MPO、MDA、XOD的值均较对照组增加,血浆中LDH的含量亦较对照组显著增加,胃粘膜组织中SOD的酶活力下降;IPC组与LIR组对比,胃结合粘液量较LIR组显著增加;胃粘膜损伤指数、胃粘膜中MPO的含量、以及胃粘膜中MDA、XOD、LDH均较LI/R组明显降低;胃粘膜中SOD酶活力增强。结论:LI/R作为应激原可引起胃粘膜损伤,导致应激性溃疡的发生;自由基在肢体缺血再/灌注后继发胃粘膜损伤过程中发挥作用。缺血预处理可减轻肢体缺血再灌注后的胃粘膜损伤,其作用机制可能是通过减少自由基的产生而发挥其保护作用。

Aim： To observe the degree of gastric mucosal injury following limb ischemia/reperfusion（LI/R）, and to investigate the mecha- nism of gastric mucosal injury and the protection of ischemic preconditioning（IPC） on gastric mucosal injury. Methods： The model rats which underwent 4 hours of ischemia and 4 hours of reperfusion of hind limbs were made. Then we respectively observed and determined the histologic lesion score after I/R and IPC ＋ I/R. The gastric barrier mucus in mucus were measured in different groups. The values of MPO , SOD , MDA and XOD in gastric mucos and the values of MDA, XOD, SOD, LDH in plasma were detected. Results： In the LI/R group, the histologic lesion score increased significantly. The content of gastric barrier mucus in mucus de- creased significantly. The value of MPO ,MDA ,XOD in gastric mucos and the values of MDA ,XOD, LDH in plasma increased remarkably and SOD activity in gastric mucos and in plasma decreased. However in the IPC group, the histologic lesion score decreased significantly and the content of gastric barrier mucus in mucus increased significantly and the value of MPO MDA XOD LDH in gastric mucos or in plasma decreased remarkably and the SOD activity increased compared to LI/R group. Conclusion： LI/R will lead to the development of stress ulcer, oxygen free radicals play an important role in it. IPC can alleviate the damage of gastric mucos following isehemia/reperfusion of hind limbs. The decrease of OFR is one of the protection mechanism of IPC.