炎症因子在小鼠肾缺血再灌注损伤相关的肺损伤中的表达

目的观察炎症因子在肾缺血再灌注损伤小鼠全身和肺组织局部表达的变化,探讨炎症反应在肾缺血再灌注损伤相关的急性肺损伤中的作用。方法选取8～10周龄雄性C57BL/6小鼠30只,随机分为假手术组（Sham组n=10）、缺血再灌注组（I/R组n=10）和双肾切除组（BNx组n=10）。分别于术后6、24h留取小鼠肾和肺组织及血浆标本,观察肾和肺组织学改变,计算肺组织中中性粒细胞浸润数,称肺湿干重,计算肺湿干重比（W/D）;ELISA法检测小鼠血清和肺冲洗液中的IL-6、IL-1β、TNF-α的浓度,实时定量PCR检测小鼠肺组织IL-6、IL-1β、TNF-α基因表达,免疫组化检测肺组织IL-6、IL-1β和TNF-α蛋白的表达。结果 I/R组和BNx组小鼠术后24h时的BUN和Scr均显著高于Sham组（P均〈0.05）,I/R组和BNx组小鼠术后24h出现肺组织炎症细胞浸润、肺泡周围毛细血管出血和肺间质水肿,两组肺组织中性粒细胞计数均高于Sham组（P〈0.05）。术后6h时I/R组和BNx组小鼠血清IL-6、IL-1β和TNF-α浓度与Sham组相比显著升高（分别为606.32±59.07和300.22±169.73vs121.52±9.12pg/ml;443.93±91.98和959.47±184.46vs21.71±2.47pg/ml,119.67±21.66和132.33±62.64vs30.21±2.46pg/ml,P均〈0.05）;I/R组和BNx组小鼠肺组织冲洗液中IL-6、IL-1β和TNF-α的水平与Sham组比较显著升高（109.74±15.91和70.00±2.42vs37.69±7.96pg/mg,117.02±27.46和215.35±18.49vs42.10±5.20pg/mg,512.31±71.95和988.25±133.55vs52.76±12.82pg/mg,P〈0.05）;术后6h肺组织IL-6、IL-1β、TNF-α的mRNA表达较Sham组显著升高（P均〈0.05）;免疫组化显示了相似的结果。结论肾缺血再灌注损伤可以介导急性肺损伤,全身和肺组织局部的炎症因子表达明显升高可能参与了肾缺血再灌注损伤相关的肺损伤。

The expression of inflammatory factors in mice with renal ischemia-reperfusion injury related lung injury

Objective To observe the expression change of inflammatory factors systemically and locally in lung tissue in mice with renal ischemia-reperfusion injury, and to understand the role of inflammatory response in renal ischemia-reperfusion injury related acute lung injury. Methods Thirty male C57BL/ 6 mice were randomly divided into control group （sham operation group, n=10）, ischemia-reperfusion group （I/R group, n=10）, or acute uremia group by bilateral nephrectomy （BNx group, n=10）. After the operations for 6 or 24 h, mice were sacrificed, and serum, lung and kidney tissues were collected. Pathological changes in kidney and lung were examined after H-E staining, and the number of infiltrated neutrophils was evaluated. The wet/dry ratio of lung was obtained by weighing wet lung and dried lung. Protein concentration in bronchoalveolar lavage （BAL） was measured by BCA method. The concentrations of IL-6, IL-1 and TNF-a in serum and BAL were assayed by ELISA. IL-6, IL-1 and TNF-a mRNAs in lung were quantified by realtime quantitative PCR. IL-6, IL-1 and TNF-a in lung were also detected by immunohistochemistry. Result In I/R and BNx groups, urea nitrogen （BUN） and Scr increased significantly after the operation for 24 h, as compared with those in sham group （P 0.05）. In I/R and BNx groups after the operation, lung tissues showed that infiltration of inflammatory cells, capillary hemorrhage around alveoli, interstitial edema, andneutrophil number were higher than those in sham group （P0.05）. In I/R, BNx and sham groups after the operation for 6 h, serum IL-6 was 606.32±59.07, 300.22±169.73 and 121.52±9.12 pg/ml, respectively; serum IL-1 was 443.93±91.98, 959.47±184.46 and 21.71±2.47 pg/ml, respectively; serum TNF-a was 119.67±21.66, 132.33±62.64 and 30.21±2.46 pg/ml, respectively. These cytokines in serum were signifi-cantly higher in I/R and BNx groups than in sham group （P0.05）. In I/R, BNx and sham groups after the operation for 6 h, BAL IL-6 was 109.74±15.91, 70.00±2.42 and 37.69±7.96 pg/mg, respectively; BAL IL-1 was 117.02±27.46, 215.35±18.49 and 42.10±5.20 pg/mg, respectively; BAL TNF-a was 512.31 ± 71.95, 988.25±133.55 and 52.76±12.82 pg/mg, respectively. These cytokines in BAL were significantly higher in I/R and BNx groups than in sham group （P0.05）. In I/R and BNx groups after the operation for 6 h, IL-6, IL-1 and TNF-a mRNAs in lung increased significantly. Immunohistochemistry for IL-6, IL-1 and TNF-a in lung demonstrated the similar results. Conclusion Renal ischemiareperfusion injury may mediate acute lung injury. The increase of inflammation factors in lung and serum may involve in the renal ischemia-reperfusion injury related lung injury.