【作者】 彭珊珊；

【导师】 张伟；

【作者基本信息】 南昌大学 ， 内科学（呼吸疾病）（专业学位）， 2018， 硕士

【摘要】 目的:建立内毒素气管内滴注诱发的急性呼吸窘迫综合征（ARDS）模型兔,采用高频振荡通气（HFOV）联合骨髓间充质干细胞移植（MSCs）治疗,探讨该方案对ARDS兔的保护作用。方法:家兔34只,2只用于制备骨髓间充质干细胞,全骨髓培养法体外培养兔MSCs,传至第3代备用。剩余32只家兔通过向气管内滴注内毒素（其主要致病成分为脂多糖LPS）建立ARDS致伤模型后,按完全随机的方法分为四组,每组8只。其中A组为ARDS对照组、B组为HFOV组、C组为MSCs移植组、D组为HFOV+MSCs移植组。分别在干预后2、6及24 h采集股动脉血,进行血气分析。将动物24 h后予以处死,用生理盐水灌洗肺组织,收集灌洗液,检测BALF中性粒细胞数目及蛋白含量;取左肺下叶称重量后,计算湿质量/干质量比值（W/D）;右肺取标本,行病理学检查。结果:1.气管内注入LPS后观察模型组实验兔均出现了呼吸急促窘迫,烦躁,四肢发绀。正常对照组在整个实验过程当中Pa O₂、Pa O₂/Fi O₂和Pa CO₂变化不明显;模型兔在经气管内注入LPS后Pa O₂、Pa O₂/Fi O₂和PaCO₂明显下降,始终显著低于正常对照组（p<0.05）;表明ARDS模型复制成功;2.动脉血气变化:HFOV+MSCs组PaO₂在三个时间均明显高于ARDS组（P<0.05）,与MSCs组及HFOV组比较,在24h时间点氧分压差异均有统计学意义（P<0.05）;且在24 h时间点PaCO₂数值上,HFOV+MSCs组明显低于其余三组（P<0.05）;3.肺组织湿/干比,支气管肺泡灌洗液:与其余三组分别比较,HFOV+MSCs组24 h肺组织W/D、BALF中性粒细胞数目及蛋白含量显著降低（P<0.05）;4.肺组织病理学改变:A组肺组织结构损伤明显,肺泡结构消失间隔增厚,肺泡腔可见渗出、出血及水肿;B组肺组织炎症细胞浸润减少,肺泡内出血渗出液明显减少,大部分肺泡正常;C组仅见散在脱落细胞,炎症细胞浸润减轻,肺泡结构相对完整,肺泡壁无增厚,肺泡腔内炎性渗出和出血明显减轻;D组肺泡结构完整,炎症细胞浸润明显减轻,可见少量肺泡内轻度红色渗出,损伤最轻。结论:1.将LPS（2mg/kg）气管内注入可以复制ARDS动物模型。2.HFOV联合MSCs可以明显改善肺组织的气体交换功能,减轻炎症反应及肺组织损伤,从而对LPS诱发的ARDS兔起到一定的保护作用,优于单一方法,具有协同作用。更多还原

【Abstract】 Objective:To investigate the prevention of endotoxin—induced acute respiratory distress syndrome in rabbit by high frequency oscillatory ventilation combined with bone marrow mesenehymal stem cells（MSCs）transplantation.Methods:A total of 34 rabbits were used in this study.Two rabbits were utilized to culture BMSCs.32 rabbits were randomly assigned to four groups:ARDS group,high frequency oscillatory ventilation（HFOV）group,BMSCs transplantation group and HFOV combined with MSCs transplantation group（n=8 for each group）.Rabbit BMSCs were isolated and cultured by the whole bone marrow culture method.At the third passage,BMSCs were harvested for transplantation.Endotoxin Was infused into the trachea to establish models of ARDS.Femoral arterial blood samples were obtained 2 h,6 h and 24 h after intervention for blood gas analysis.24 h after intervention,the upper lobe of left lung Was weighed for calculating wet-to-dry weight ratio（W/D）.The right lung Was lavaged with 10 mL of saline in order to detect the number of neutrophils and protein content in the lavage fluid.The lower lobe of left lung Was excised for histological observation.Results:1.Intratracheal injection of LPS were observed in model group rabbits showed shortness of breath distress,irritability,limbs cyanosis.In normal control group,Pa O₂,Pa O₂/Fi O₂ and Pa CO₂ remained relatively stable throughout the whole experimental process.In model group,Pa O₂,Pa O₂/Fi O₂ and Pa CO₂decreased significantly after LPS was injected into the trachea.It was always significantly lower than the normal control group（p<0.05）;It shows that the replication of ARDS model is successful.2.Arterial blood gas change:Pa0₂ in the HFOV+MSCs group at three time points were higher than those in ARDS groups,respectively（P<0.05）.Pa0₂ in HFOV+MSCs group at 24 h was also compared to MSCs group and HFOV group respectively,and the differences were statistically significant（P<0.05）;PaC0₂ in the HFOV+MSCs group at 24 h was significantly lower than those in the other three groups（P<0.05）.3.Lung tissue wet/dry ratio,bronchoalveolar lavage fluid:Compared with the other three groups,the number of neutrophils and protein content in W/D and bronchoalveolar lavage fluid in group HFOV+MSCs and 24 h were significantly decreased（P<0.05）.The HFOV+MSCs group at 24 h was significantly reduced in W/D,bronchoalveolar lavage fluid neutrophil number and protein content compared with the other three groups.4.Pathological changes of lung tissue:In group A,lung tissue structure was damaged obviously,alveolar structure disappeared,diffuse alveolar cavity appeared,edema and hemorrhage,alveolar septal thickening.In group B,infiltration of inflammatory cells decreased,alveolar hemorrhage and exudate decreased significantly,and most alveolar cells were normal.In group C,only scattered cells were scattered,inflammatory exudation and bleeding were obviously alleviated in the alveolar cavity,the alveolar wall was not thickened,the infiltration of inflammatory cells was reduced,and the alveolar structure was relatively complete.In group D,the inflammatory reaction in lung tissue was significantly reduced,alveolar structure was intact,and a small amount of red exudation in the alveoli was the least lightest.The lung histological injury was lowest in HFOV+MSCs group and significantly reduced in HFOV and MSCs group.Conclusions:1.Intratracheal injection of LPS（2mg/kg）can replicate ARDS animal model.2.HFOV combined with MSCs can obviously improve the gas exchange function of lung tissue,reduce the degree of inflammatory reaction and lung injury,and thus protect the rabbit ARDS caused by LPS,which is better than a single method,and has synergistic effect.更多还原