肺组织CD14、TLR4受体易感性在老年大鼠多器官功能障碍综合征中作用机制研究

发布时间：2018-06-20 17:56

本文选题：多器官功能障碍综合征 + 急性呼吸窘迫综合征　；参考：《第三军医大学》2005年博士论文

【摘要】：老年多器官功能障碍综合征(MODSE)往往继发于肺部感染且以肺损伤出现最早,表明老年肺脏更易受到脂多糖(LPS)的攻击,在MODSE发生过程中起着更为关键的作用。其原因可能是老年肺脏对LPS敏感性增强所致。本课题采用油酸(OA)和LPS致伤SD大鼠,建立二次致伤MODSE和青年多器官功能障碍综合征(MODSY)动物模型对比观察各自脏器损伤的特点及差异,在此模型的基础上,检测肺、心、肝、肾不同脏器组织中细胞因子TNF-α、IL-6蛋白及mRNA表达,内毒素含量,以及CD14、TLR4受体mRNA及蛋白表达变化,并检测肺组织中转录因子NF-κB活化情况,从老年鼠肺组织CD14、TLR4受体易感性及其对内毒素亲和性的角度,探讨老年肺易损机制,及其在MODSE发生中的作用。方法: 1.建立OA/LPS二次致伤MODSE和MODSY大鼠模型。 2.ELISA法检测血浆及肺、心、肝、肾组织中细胞因子TNF-α、IL-6蛋白含量,RT-PCR检测上述组织中mRNA表达。 3.鲎试剂凝胶法检测肺、心、肝、肾组织中内毒素含量。 4.RT-PCR检测肺、心、肝、肾组织中CD14、TLR4 mRNA表达水平,免疫组化方法检测其蛋白表达。 5.免疫组化方法检测肺组织中转录因子NF-κB活化情况。结果: 1.OA/LPS致伤后2h,青年组和老年组PaO_2降至最低值(分别为67.5±8.66mmHg,59.3±7.41mmHg,P0.01),心、肝、肾生化指标于6h达峰值(P0.05～0.01),且老年组脏器损害较同时相点青年组严重(P0.05～0.01)。符合动物MODS诊断标准。 2.伤后2h,血清及肺、心、肝和肾组织中TNF-α、IL-6含量和组织中mRNA表达显著升高达峰值,且持续高于正常对照组(P0.05～0.01),以肺组织升高幅度最大。老年组2h、6h时相点TNF-α、IL-6含量和mRNA表达均显著高于同时相点的青年组(P0.05)。
[Abstract]:Multiple organ dysfunction syndrome (MODSE) in the elderly is usually secondary to pulmonary infection and the earliest occurrence of lung injury, indicating that the elderly lung is more vulnerable to the LPSs attack, and plays a more critical role in the pathogenesis of MODSE. This may be due to the increased sensitivity of the elderly lung to LPS. In this study, SD rats were injured by oleic acid (OAA) and lipopolysaccharide (LPS). The animal models of secondary injury MODSE and young multiple organ dysfunction syndrome (MODSYS) were established to observe the characteristics and differences of organ injury. On the basis of the model, lung, heart and liver were detected. The expression of TNF- 伪 and IL-6 protein and mRNA, the content of endotoxin, the expression of CD14 TLR4 receptor mRNA and protein in different organs of kidney, and the activation of transcription factor NF- 魏 B in lung tissue were detected. From the point of view of susceptibility of CD14 TLR4 receptor and its affinity to endotoxin in aged rats, the mechanism of lung damage and its role in the pathogenesis of MODSE were discussed. Methods: 1. The model of MODSE and MODSY rats with secondary injury induced by OAP / LPS was established. 2. Elisa was used to detect plasma, lung, heart and liver. The protein content of TNF- 伪 and IL-6 in renal tissue was detected by RT-PCR. 3. 3. The content of endotoxin in lung, heart, liver and kidney was detected by Limulus amebocyte lysate gel method. 4. The expression of CD14 TLR4 mRNA in lung, heart, liver and kidney was detected by reverse transcription-polymerase chain reaction (RT-PCR). Immunohistochemical method was used to detect its protein expression. 5. 5. The activation of NF-魏 B in lung tissue was detected by immunohistochemistry. Results: 1. At 2 h after OAP / LPS injury, PaO-2 decreased to the lowest value in young group and old group (67.5 卤8.66 mm HgGN 59.3 卤7.41 mm HgP 0.01, heart, liver, respectively). The renal biochemical index reached the peak value at 6 h, and the organ damage in the elderly group was more serious than that in the young group at the same time. In accordance with animal mods diagnostic criteria. 2. TNF- 伪 IL-6 content and mRNA expression in serum, lung, heart, liver and kidney increased to the peak at 2 h after injury, and continued to be higher than that in the normal control group (P 0.05), especially in lung tissue. The content and mRNA expression of TNF- 伪 IL-6 in the aged group were significantly higher than those in the young group at 2 h or 6 h.
【学位授予单位】：第三军医大学
【学位级别】：博士
【学位授予年份】：2005
【分类号】：R363

【参考文献】