短期间歇性闭合式腹腔灌洗治疗大鼠早期重症胰腺炎的免疫机制

Effect of short-term intermittent peritoneal lavage on immune function in rats with early severe acute pancreatitis

目的:建立L-精氨酸诱导的重症急性胰腺炎大鼠模型,研究腹膜透析液腹腔灌洗治疗下Toll样受体4(Toll like receptor4,TLR4)、单核-巨噬细胞表面可溶性抗原(soluble CD14,sCD14)、核因子κB(nuclear factor κB,NF-κB)在其免疫机制中的作用.方法:腹腔注射70g/L的L-精氨酸(3.5g/100g)制成重症急性胰腺炎大鼠模型.48只大鼠,随机分成3组:SAP模型组(12、24、36h,每组6只);对照组(12、24、36h,每组4只);灌洗组(12、24、36h,每组6只).模型组和对照组分别腹腔注射70g/L的L-精氨酸(3.5g/100g,分3次注射,1次/h)和等量0.9%生理盐水(分3次注射,1次/h)后12、24、36h麻醉处死.灌洗组在造模后1h于腹部上、下方置管行腹膜透析液腹腔灌洗(1次/6h,100mL/次,灌洗速度60滴/min左右;12h组灌洗2次,24h组灌洗4次,36h组灌洗6次),完成灌洗后即刻处死大鼠.测定血清淀粉酶、脂肪酶含量及血TLR4、sCD14浓度,观察胰腺组织病理学改变和胰腺组织NF-κB表达水平.结果:L-精氨酸诱导重症急性胰腺炎大鼠模型成功.灌洗组血清淀粉酶、脂肪酶含量较模型组降低(12h:1253.3±195.2vs1953.3±316.9,20.0±6.5vs86.3±36.8;24h:2299.2±416.4vs4047.7±589.3,33.7±15.5vs238.2±73.2;36h:1581.3±391.6vs2327.8±354.6,22.0±9.3vs158.3±38.5,均P<0.05),较对照组无明显统计学意义(P>0.05).灌洗组胰腺组织病理学评分较模型组和对照组均有统计学意义(P<0.05).灌洗组血TLR4、sCD14浓度在各时点较模型组降低(P<0.05),较对照组无明显统计学意义(P>0.05).灌洗组胰腺组织NF-κB表达水平较模型组下降,对照组NF-κB表达较少或基本无表达.结论:短期间歇性闭合式腹腔灌洗对早期重症急性胰腺炎大鼠有较好的免疫抑制作用.

AIM： To analyze the role of Toll-like receptor 4 （TLR4）, soluble CD14 （sCD14） on monocyte- macrophage cell surface, and nuclear factor loB （NF-kB） in immune mechanisms involved in the therapeutic effect of peritoneal lavage against L-arginine-induced severe acute pan- creatitis in rats. METHODS： Severe acute pancreatitis was in- duced in rats by intraperitoneal injection of L-arginine （3.5 g/100 g） at a concentration of 70 g/L. Forty-eight rats were randomly divided into three groups： severe acute pancreatitis group （for testing at 12, 24, and 36 h, 6 rats per subgroup）, control group （12, 24, and 36 h, 4 rats per subgroup）, and lavage group （12, 24, and 36 h, 6 rats per subgroup）. Rats of the severe acute pancreatitis group were killed at 12, 24 and 36 h after modeling. Rats of the control group were also killed at the above point of time after intra- peritoneal injection of normal saline. Rats of the lavage group were catheterized in the upper and lower abdomen for peritoneal lavage at I h after modeling （100 mL, once per 6 h, lavage speed at 60 drops/min; 12 h subgroup, twice; 24 h sub- group, four times; 36 h subgroup, six times）. Af- ter the lavage was finished, the rats were killed. The contents of serum amylase and lipase and the concentrations of TLR4 and sCD14 in the blood were determined, and histopathological changes and expression levels of NF-kB in the pancreatic tissue were observed. RESULTS： The rat model of severe acute pan- creafitis was successfully replicated by intraperi- toneal injection of L-arginine. The contents of se- rum amylase and lipase in the lavage group were significantly lower than those in the severe acute pancreatitis group （12 h： 1 253.3 ± 195.2 vs 1 953.3 ± 316.9, 20.0 ± 6.5 vs 86.3 ± 36.8; 24 h： 2 299.2 ±416.4 vs 4 047.7± 589.3, 33.7 ±15.5 vs 238.2 ±73.2; 36 h： 1 581.3± 391.6 vs 2 327.8 ± 354.6, 22.0±9.3 vs 158.3 ± 38.5, all P 〈 0.05）, but showed no signifi- cant difference compared to the control group （all P 〉 0.05）. Pathological changes in the pancreatic tissue in the lavage group were significantly im- proved compared to the severe acute pancreatitis group and control group （both P 〈 0.05）. The concentrations of TLR4 and sCD14 in the blood were significantly lower in the lavage group than in the severe acute pancreatitis group （P 〈 0.05）, but showed no statistically significant difference compared with the control group at various time points. Expression of NF-KB in the pancreatic tissue was lower in the lavage group than in the severe acute pancreatitis group, but was almost undetectable in the control group.CONCLUSION： Short-term intermittent perito- neal lavage has a remarkable inhibitory effect on immune function in rats with early severe acute pancreatitis.