不同致病因素致脓毒性休克早期多糖包被变化的研究

A study on the changes of endothelial glycocalyx in rabbits with septic shock induced by different factors

目的建立脓毒性休克兔模型,初步观察在不同致病因素打击下内皮多糖包被的损伤情况。方法采用随机数字表法将36只雄性新西兰兔分为盲肠结扎穿孔(cecal ligation and puncture,CLP)组、CLP对照组、CLP30mL组、脂多糖(lipopolysaccharide,LPS)组、LPS对照组、LPS 30mL组各6只,分别复制CLP及LPS动物模型后,记录成模时间及临床指标,CLP 30mL组和LPS 30mL组给予静脉泵入去甲肾上腺素联合30mL/kg液体复苏。并于模型建立后早期不同时间点检测血浆多糖包被标志物浓度,成模6h后活杀动物留取肾脏组织,分别采用免疫组织化学和Western blot方法检测多糖包被表达情况。结果 2种动物模型成模时间差异有统计学意义(P<0.05),血白细胞计数和乳酸值差异均无统计学意义(P>0.05)。LPS组和CLP组中心静脉血氧饱和度均低于LPS对照组和CLP对照组,LPS组高于CLP组,差异有统计学意义(P<0.05);血浆多糖包被标志物syndecan-1均明显升高,且CLP组高于LPS组(P<0.05)。HE染色观察发现2种动物模型LPS组肾组织损伤低于CLP组,肾组织免疫组织化学检测显示LPS组syndecan-1染色深,其程度大于CLP组。应用Western blot对2种模型及液体复苏后的syndecan-1蛋白在肾组织表达量进行比较,LPS各组syndecan-1表达量明显高于CLP组。结论 LPS和CLP均可导致内皮多糖包被的损伤。前者的内皮多糖包被的损伤程度较后者轻。经适当液体复苏联合去甲肾上腺素治疗后,短期内多糖包被在LPS部分恢复的可能性较大。

Objective To observe the alterations of endothelial glycocalyx in early septic shock rabbits induced by different pathogenic factors.Methods Thirty-six male New Zealand rabbits were divided into puncture cecal ligation and puncture(CLP)group,the CLP control group,the CLP30mL group,the lipopolysaccharide(LPS)group,the LPS control group and the LPS30mL group,6rabbits in each group according to a random number table.After establishment of rabbit model of LPS and CLP induced septic shock,they were managed accordingly and the clinical indicators and time for model establishment of each group were recorded and compared.Concentrations of syndecan-1in plasma were measured by enzyme linked immunosorbent assay at different time points early after septic model was established.After six hours,the rabbits were sacrificed,and various organs and tissues were harvested.Western blot and immunohistochemistry were used to detect the expression of endothelial glycocalyx.Results The modeling time of CLP group and LPS group was significantly different(P<0.05).There were no statistical differencesin white blood cell count and lactic acid between CLP group and LPS group(P>0.05),as well as between CLP control group and LPS control group(P>0.05).However,significant differences were found between model group and control group.In addition,model group and control group showed significant differences in central venous blood oxygen saturation(P<0.05),as well as between LPS group and CLP group(P<0.05).Results of plasma markers revealed that the concentration of plasma syndecan-1was significantly higher in CLP group than in LPS group.HE staining revealed less renal damage in LPS group than in CLP group.Immunohistochemical results showed that the expression of syndencan-1which was darker and higher in LPS group than in CLP group.Western blot results indicated that the expressions of syndecan-1in renal tissues in LPS groups were higher than that in CLP groups.Conclusion The endothelial glycocalyx was damaged by both LPS and CLP.LPS caused less damage to endothelial glycocalyx than CLP.After fluid resuscitationcombined with norepinephrine,endothelial glycocalyx will be more likely to be partially restored in LPS group in a short term.