论文部分内容阅读
目的:探讨亚低温能否抑制脓毒症小鼠白细胞介素-3（IL-3）的表达与释放，从而对脓毒症小鼠起保护性作用。方法:120只雄性C57BL/6小鼠按随机数字表法分成假手术组（Sham组）、脓毒症常温组（NT组）、脓毒症亚低温组（HT组），每组40只。采用盲肠结扎穿孔术（CLP）制备小鼠急性脓毒症模型，HT组术后1 h予以亚低温治疗，控制肛温在32～34 ℃，亚低温干预8 h后缓慢复温；NT组CLP术后常规复苏小鼠，维持肛温在36～38 ℃；Sham组不结扎和刺破盲肠，常规复苏。每组取20只小鼠监测术后12 h平均动脉压（MAP）并观察术后4 d死亡情况及生存时间；其余小鼠于术后12 h留取血清并处死取材，用酶联免疫吸附试验（ELISA）测定血清IL-3、白细胞介素-6（IL-6）及肿瘤坏死因子-α（TNF-α）水平；用蛋白质免疫印迹试验（Western blotting）检测脾组织和肺组织IL-3蛋白的表达。光镜下观察肺组织及肝组织病理改变并进行半定量评分。结果:NT组和HT组MAP随CLP术后时间延长而下降，HT组在术后10 h、12 h MAP（mmHg，1 mmHg＝0.133 kPa）明显高于NT组（10 h：74.4±12.4比62.9±7.2，12 h：68.4±3.7比57.5±9.6，均n P<0.01）。与Sham组比较，NT组和HT组在CLP术后12 h血清IL-3、IL-6、TNF-α水平均显著升高〔IL-3（ng/L）：2.21±0.87、0.18±0.04比0，IL-6（ng/L）：51.22±18.65、24.68±6.20比1.36±0.34，TNF-α（ng/L）：101.43±38.60、72.15±25.12比14.49±5.17，均n P<0.01〕；与Sham组比较，NT组和HT组脾组织、肺组织IL-3蛋白表达显著升高（IL-3/β-actin：脾组织0.200±0.039、0.135±0.023比0.090±0.023，肺组织0.085±0.009、0.056±0.009比0.039±0.005，均n P<0.01）。HT组小鼠血清中IL-3、IL-6、TNF-α水平较NT组明显下降〔IL-3（ng/L）：0.18±0.04比2.21±0.87，IL-6（ng/L）：24.68±6.20比51.22±18.65，TNF-α（ng/L）：72.15±25.12比101.43±38.60，均n P<0.01〕；HT组脾组织、肺组织IL-3蛋白表达较NT组显著下降（IL-3/β-actin：脾组织0.135±0.023比0.200±0.039，肺组织0.056±0.009比0.085±0.009，均n P<0.01）。HT组肺组织损伤评分及肝组织损伤评分较NT组显著降低〔肺组织损伤评分（分）：4.00±1.41比6.67±2.16，n P＝0.03；肝组织损伤评分（分）：3.83±1.47比7.17±2.14，n P＝0.01〕。与NT组比较，HT组小鼠4 d存活率显著提高（50%比30%，n P<0.01）。n 结论:亚低温可显著抑制脓毒症小鼠IL-3的表达与释放，减轻器官损伤，对脓毒症小鼠起护性作用。“,”Objective:To investigate whether or not mild hypothermia can inhibit the expression and release of interleukin-3 (IL-3) in septic mice and whether it has a protective effect on septic mice.Methods:According to random number table method, 120 male C57BL/6 mice were divided into sham operation group (Sham group), sepsis normal temperature group (NT group) and sepsis mild hypothermia group (HT group), with 40 mice in each group. The acute septic mice model was established by cecal ligation and puncture (CLP) method. In the HT group, body temperature decreased to 32-34 ℃ at 1 hour after CLP and was maintained for 8 hours, followed by rewarming slowly to 36-38 ℃. In the NT group, mice were resuscitated after CLP and body temperature was maintained at 36-38 ℃ throughout the experimental periods, while in Sham group, the cecum was not ligated or punctured and resuscitated routinely. The average arterial pressure (MAP) of 20 mice in each group was monitored for 12 hours after CLP, and the survival time was observed for 4 days. The serum of remaining mice was collected at 12 hours after CLP, and the mice were killed for organ tissues. The serum levels of IL-3, interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α) were determined by enzyme linked immunosorbent assay (ELISA). Western blotting was used to detect IL-3 protein expression in spleen and lung tissues. The pathological changes of lung and liver tissues were observed under microscope and the semi-quantitative scoring was performed.Results:MAP of NT group and HT group decreased after CLP with the prolongation of time. MAP (mmHg, 1 mmHg = 0.133 kPa) of HT group at 10 hours and 12 hours after CLP were significantly higher than those of NT group (10 hours: 74.4±12.4 vs. 62.9±7.2, 12 hours: 68.4±3.7 vs. 57.5±9.6, both n P < 0.01). Compared with Sham group, serum levels of IL-3, IL-6 and TNF-α in NT group and HT group were significantly increased at 12 hours after CLP [IL-3 (ng/L): 2.21±0.87, 0.18±0.04 vs. 0, IL-6 (ng/L): 51.22±18.65, 24.68±6.20 vs. 1.36±0.34, TNF-α (ng/L): 101.43±38.60, 72.15±25.12 vs. 14.49±5.17, all n P < 0.01]. IL-3 protein expressions of spleen and lung tissues in NT group and HT group were significantly increased compared to those in Sham group (IL-3/β-actin: spleen tissue 0.200±0.039, 0.135±0.023 vs. 0.090±0.023, lung tissue 0.085±0.009, 0.056±0.009 vs. 0.039±0.005, all n P < 0.01). The serum levels of IL-3, IL-6 and TNF-α were significantly lower in HT group than those in the NT group [IL-3 (ng/L): 0.18±0.04 vs. 2.21±0.87, IL-6 (ng/L): 24.68±6.20 vs. 51.22±18.65, TNF-α (ng/L): 72.15±25.12 vs. 101.43±38.60, all n P < 0.01]. The expressions of IL-3 protein in HT group were significantly lower than those in NT group (IL-3/β-actin: spleen tissue 0.135±0.023 vs. 0.200±0.039, lung tissue 0.056±0.009 vs. 0.085±0.009, both n P < 0.01). The lung tissue injury and liver tissue injury scores in HT group were significantly lower than those in NT group (lung tissue injury score: 4.00±1.41 vs. 6.67±2.16, n P = 0.03, liver tissue injury score: 3.83±1.47 vs. 7.17±2.14, n P = 0.01). Compared to NT group, the 4-day survival rate of HT group was significantly improved (50% vs. 30%, n P < 0.01).n Conclusion:Mild hypothermia can significantly inhibit the expression and release of IL-3 in septic mice, attenuate organ injury, and protecte septic mice.