目的：观察多器官功能障碍综合征（MODS）家猪内皮祖细胞（EPC）的数量与功能，探讨创伤后MODS的发病机制。方法将40头家猪按随机数字表法分为假手术组和实验组，每组20头。采取失血性休克和内毒素血症的“二次打击法”制备MODS动物模型。分别于失血前（T1）、内毒素注射前（T2）及注射后1、24、48 h（T3、T4、T5）取外周静脉血，采用蛋白质免疫印迹试验（Western Blot）检测外周血单核细胞磷酸化p38丝裂素活化蛋白激酶（p-p38MAPK）的表达；酶联免疫吸附试验（ELISA）检测血浆肿瘤坏死因子-α（TNF-α）浓度；流式细胞仪检测外周血EPC数量。结果实验组有17头家猪成功复制MODS模型，动物的外周血单核细胞p-p38MAPK表达（A值）于T3时达到高峰（4.83±0.52），T4、T5时逐渐下降（4.36±0.43、1.93±0.33），T3、T4、T5时均显著高于T1时（1.00±0.22，均P＜0.01）。实验组血浆TNF-α浓度（ng/L）于T3时显著高于假手术组并达高峰（532.43±52.17比129.03±20.45，t＝31.163，P＜0.001），随后逐渐下降，T4、T5时仍显著高于假手术组（T4：398.93±35.75比131.12±29.53，t＝26.562，P＜0.001；T5：287.48±27.26比126.44±26.96，t＝17.861，P＜0.001）。实验组外周血EPC数量（×107/L）于T3时显著高于假手术组并达高峰（4.832±0.624比3.545±0.363，t＝9.542，P＜0.001），随后逐渐下降，T4、T5时显著低于假手术组（T4：2.628±0.627比3.442±0.325，t＝5.043，P＜0.001；T5：2.203±0.711比3.471±0.323，t＝2.972，P＜0.001）。结论在创伤性MODS的发生机制中，外周血单核细胞中p38MAPK的磷酸化可以促使血浆中TNF-α浓度升高，EPC数量下降，可能为其机制之一。%Objective To study the modulation in number and function of endothelial progenitor cell ( EPC ) in multiple organ dysfunction syndrome ( MODS ) after trauma in swine, and to investigate its pathogenesis. Methods Forty pigs were divided into sham group and MODS group ( each, n = 20 ). The model of MODS of "two-hit" injury, namely hemorrhagic shock and endotoxemia, was reproduced. The peripheral blood was collected before hemorrhage ( T1 ) and endotoxin injection ( T2 ), and 1 hour ( T3 ), 24 hours ( T4 ), 48 hours ( T5 ) after endotoxin injection. Phosphorylation of p38 mitogen-activated protein kinase ( p-p38MAPK ) in mononuclear cell was determined by Western Blot, the content of tumor necrosis factor-α ( TNF-α) was determined with enzyme linked immunosorbent assay ( ELISA ), and the number of EPC was determined with flow cytometry. Results Model of MODS was successfully reproduced in 17 pigs. In model group, the expression of p-p38MAPK ( A value ) peaked at T3 ( 4.83±0.52 ), and gradually declined at T4 and T5 ( 4.36±0.43, 1.93±0.33 ), and the expression of p-p38MAPK at T3-T5 was significantly higher than that at T1 ( 1.00±0.22, all P<0.01 ). The plasma concentration of TNF-α( ng/L ) at T3 in MODS group was obviously elevated compared with that of sham group ( 532.43±52.17 vs. 129.03±20.45, t=31.163, P<0.001 ), and it peaked at T3, it then gradually lowered, and it was significantly higher at T4 and T5 than that in sham group ( T4: 398.93±35.75 vs. 131.12±29.53, t = 26.562, P < 0.001; T5: 287.48±27.26 vs. 126.44±26.96, t=17.861, P<0.001 ). The number of EPC ( ×107/L ) was apparently increased in MODS group at T3 compared with sham group ( 4.832±0.624 vs. 3.545±0.363, t=9.542, P<0.001 ), and it peaked at T3, then gradually decreased, and the number of EPC at T4 and T5 was significantly lower than that in sham group ( T4:2.628±0.627 vs. 3.442±0.325, t=5.043, P<0.001;T5:2.203±0.711 vs. 3.471±0.323, t=2.972, P<0.001 ). Conclusion Phosphorylation of p38MAPK could increase the plasma concentration of TNF-αand decrease the quantity of EPC in MODS,which may be one of the mechanisms of MODS.
展开▼
