远端缺血预适应对肠缺血再灌注损伤防护作用的研究

目的 通过建立大鼠远端缺血预适应(RIPC)和肠缺血再灌注损伤模型,探讨RIPC对肠缺血再灌注损伤是否有防护作用.方法 雄性SD大鼠分为肠缺血再灌注(L/R)组(8只)、RIPC组(8只)和假手术组(Sham组,5只).用充气套囊加压阻断右侧上下肢体血供5 min后放气恢复血供5 min的方法重复3次首先建立大鼠肢体缺血预适应模型.后经正中剖腹,阻断腹腔干动脉和肠系膜上动脉30 min后,恢复血运2h制作鼠肠缺血再灌注模型.取肠组织分别作苏木素-伊红染色、聚腺苷二磷酸核糖(PAR)免疫组织化学染色、原位凋亡检测、髓过氧化酶( MPO)活性和丙二醛检测.结果 肠组织损伤评分、PAR阳性表达率、MPO活性和丙二醛水平,I/R组均较Sham组明显增高[(4.65±0.82)分比(0.56±0.48)分,(23.8±2.8)％比(5.1±0.8)％；(330±15)U/g比(24±5)U/g；(248±15)μmol/( L· mg)比(36±7)μmol/(L·mg),均P＜0.05]；RIPC组上述指标[(2.92±0.74),(16.8±3.1)％,(218±17) U/g,(121±13) μmol/(L· mg)]均明显低于I/R组,但仍高于Sham组(P＜0.05).结论 RIPC可能会通过抑制肠炎症反应、脂质过氧化和降低PARP激活程度来减轻I/R后小肠组织损伤.

Effect of remote ischemic preconditioning on intestinal ischenia-reperfusion injury

Objective To investigate the effect of remote ischemic preconditioning （RICP） on intestinal is- chemia-reperfusion （I/R） injury in a rat model. Methods The model of remote isehemie preconditioning in rats was made by 3 x 5-min cycles of fight upper arm/leg ischemia and 5-min reperfusion. Then intestinal I/R was estab- lished by clamping both the celiac trunk and the superior mesenterie artery for 30 min, followed by reperfusion for 2h. The animals were assigned to different groups： I/R group, RICP group and Sham group. The morphological changes of intestine, PARP-1 activation, apoptosis were detected by means of HE,immunohistochemical staining for poly （ADP-ribose） and TUNEL. Regional inflammatory reaction and lipid peroxidation were indicated by myeloper- oxidase （MPO） activity and malonaldehyde （MDA）. Results In I/R group, the extent of intestinal injure and PARP-1 activation, Compared with Sham group, TUNEL positive-staining, MPO activity and MDA were elevated significantly in I/R group [ （ 4. 65± 0. 82） vs （0. 56 ± 0.48 ）, （ 23. 8 ±2. 8 ） % vs （ 5. 1 ±0. 8 ） % ; （ 330±15 ） U/g vs （24±5）U/g; （248± 15） μmol/（L.mg） vs （36 ±7）μmol/（L.mg） ,P 〈0. 05） ]. In RICP group, these variables [ （ 2. 92± 0. 74 ）, （ 16. 8±3. 1 ） %, （ 218±17 ） U/g, （ 121± 13 ） μmol/（ L.mg ） ] were statistically lower than those in I/R group （ P 〈 0. 05 ）, but higher than those of Sham group （ P 〈 0.05 ）. Condusion These findings demonstrat that RICP has the potential protection from intestinal I/R, which could be induced by inhibiting regional inflammatory reaction,lipid peroxidation and PARP-1 activation.