清热活血调气方对坏死性小肠结肠炎模型新生大鼠Toll样受体4、核因子-κB表达及细菌易位的影响

摘要

[目的]探讨清热活血调气方对坏死性小肠结肠炎(NEC)模型新生大鼠回肠组织Toll样受体4(TLR4) mRNA、核因子-κB (NF-κB) mRNA表达及细菌易位的影响.[方法]选用3日龄SD新生大鼠随机分为3组:正常对照组、NEC模型组及治疗组.采用鼠代乳品人工喂养及缺氧冷刺激的方法,复制新生大鼠NEC模型.治疗组采用鼠乳代用品+清热活血调气方(15 g·kg-1·次-1,3次/d)人工喂养,同时予以缺氧冷刺激;正常对照组鼠乳喂养,不进行任何干预.第4天心脏穿刺采血后处死大鼠取近回盲部末端回肠2 cm,采用实时荧光定量PCR法检测回肠组织TLR4 mRNA、NF-κB mRNA 表达水平及血标本中细菌16S rRNA进而得出细菌易位发生率.[结果]与模型组比较,治疗组TLR4 mRNA、NF-κB mRNA 表达水平显著下降(P＜0.01),细菌易位发生率显著降低(P＜0.05).[结论]清热活血调气方可下调NEC模型新生大鼠回肠组织TLR4 mRNA、NF-κB mRNA表达,减少细菌易位的发生.%Objective To observe the effect of Qingre Huoxue Tiaoqi Recipe (QHTR) on mRNA expression of Toll-like receptor 4 (TLR4) and nuclear factor kappa B (NF-KB) and on bacterial translocation in neonatal ramodel of necrotizing enterocolitis (NEC). Methods Three-day-old neonatal SD rats were randomly divided into three groups; normal control group, NEC model group and treatment group. NEC rat model was established by feeding with rat-milk substitutes, and by exposing to 100% nitrogen gas for 90s and cold stress (4℃ ) for 10 min, twice per day for 3 days. The rats in the treatment group received QHTR ( 15 g o kg-1 each time, 3 times per day) mixed into the milk substitutes, and were simultaneously given hypoxia and cold stress. Rats in the normal control group were raised by their mothers and had no any intervention. After blood sampling via cardiac puncture, the rats were executed and 2-cm terminal ileum segment proximal to the ileocecal valve were obtained from the rats on the 4th day. Fluorescence quantitative PCR was applied to evaluate the levels of TLR4 mRNA and NF-KB mRNA, and to detect the bacterial DNA in blood samples for examining the incidence of bacterial translocation ( BT). Results Compared with NEC model group, the levels of TLR4 mRNA and NF-KB mRNA were significantly reduced ( P < 0. 01) and the incidence of bacterial translocation was significantly decreased (P < 0.05) in the treatment group. Conclusion QHTR shows certain effect on down-regulating the levels of TLR4 mRNA and NF-KB mRNA expression, and on decreasing the incidence of bacterial translocation in the ileum of NEC rats.