摘要
目的 :研究腹腔感染后主要脏器 Toll样受体 (TL R) 2 / 4 m RNA表达的变化规律及组织分布特点 ,并对其诱生机制进行初步探讨。方法 :采用大鼠盲肠结扎穿孔 (CL P)造成严重脓毒症模型。动物分为正常对照组(10只 )、假手术组 (10只 )、CL P组 (6 0只 )及杀菌 /通透性增加蛋白 (BPI)治疗组 (2 0只 )。分别检测肝、肺、肾、小肠组织 TL R2 / 4 m RNA表达及血浆肿瘤坏死因子α(TNFα)和白介素 10 (IL 10 )水平。结果 :CL P后 2 h肝、肺、肾及小肠组织中 TL R2 / 4 m RNA表达开始增高 ,伤后 6～ 12 h各组织 TL R2 / 4 m RNA表达迅速达峰值。 TL R4 m RNA表达于伤后 2 4～ 4 8h开始下降 ,CL P后 72 h趋于伤前范围甚至阴性 ,而 TL R2 m RNA表达则持续增高至 72 h。早期给予 BPI治疗后 ,动物 12～ 2 4 h肝、肺、肾及小肠组织 TL R2 m RNA水平均显著降低(P<0 .0 5或 P<0 .0 1) ,同时 CL P后 12 h各组织 TL R4 m RNA表达亦不同程度下调 (P<0 .0 5或 P<0 .0 1)。BPI治疗组伤后 12 h血浆 TNFα水平显著降低 (P<0 .0 5 ) ,恢复至伤前正常范围 ,但伤后 2 4 h血浆 IL 10水平显著升高 (P<0 .0 1)。结论 :严重腹腔感染可迅速上调体内多器官 TL R2 / 4的基因表达 ,诱导促炎细胞因子产生 ,TL
Objective: To investigate the changes in Toll-like receptor (TLR) 2 and 4 gene expression in vital organs in septic rats and their potential regulation mechanism. Methods: One hundred Wistar rats were randomly divided into normal controls (n=10), sham-operated group (n=10), septic group (n=60), and recombinant bactericidal/permeability increasing protein (BPI)-treated group (n=20). Severe sepsis was replicated by cecal ligation and puncture (CLP). Animals were sacrificed at different time points after CLP, tissue TLR2/4 mRNA expression in the liver, lungs, kidneys as well as intestine were measured by reverse transcription-polymerase chain reaction (RT-PCR). Plasma levels of tumor necrosis factor-α(TNF-α) and interleukin-10 (IL-10) were also determined by enzyme linked immunoadsorbent assay(ELISA). Results: TLR2/4 mRNA could be detected in various tissues with low values both in normal controls and sham- operated group, but they were markedly up-regulated at 2 hours after CLP, peaking at 6-12 hours. Tissue TLR4 mRNA was gradually down-regulated 24 hours later, while TLR2 mRNA levels maintained high values up to 72 hours. In comparison with the CLP group, treatment with BPI significantly decreased TLR2 mRNA in various tissues at 12 and 24 hours (P<0.05 or P<0.01), also tissue TLR4 mRNA at 12 hours ( P<0.05 or P<0.01), without marked influence on TLR4 mRNA expression at 24 hours in liver, lungs and small intestine (P>0.05). In addition, treatment with BPI could significantly lower plasma TNF-α levels at 12 hours post-CLP, on the other hand markedly elevate plasma IL-10 levels 24 hours later (P<0.01). Conclusion: These data suggest that severe peritoneal infection could result in up-regulation of TLR2/4 mRNA expression in vital organs, which might play important roles in mediating proinflammatory cytokine synthesis and release. Endotoxemia appears to be involved in the activation of tissue TLR2/4 expression associated with CLP-induced sepsis.
出处
《中国危重病急救医学》
CAS
CSCD
2003年第11期646-650,共5页
Chinese Critical Care Medicine
基金
国家重点基础研究发展规划项目(G19990542032)
国家杰出青年科学基金(30125020)
北京市"十五"科技计划重大项(H020920020530)
军队"十五"医药卫生科研基金(01MA207)
