析因设计评价盲肠结扎穿孔(CLP)脓毒症大鼠模型严重程度的影响因素

目的目的探究盲肠结扎穿孔(CLP)脓毒症大鼠模型严重程度的影响因素。方法以盲肠结扎比例、穿刺针型号、抗生素使用情况为研究因素,分别选择结扎比例25%、50%、75%三种结扎方式,12号、16号穿刺针两种型号,使用抗生素与未使用抗生素两种情况,按照3×2×2型析因实验设计方法将84大鼠按随机数字表法随机分为14组,每组6只,建立CLP大鼠模型,以大鼠生存率、24h肝脏IL-1α、TNF-α、IL-6细胞因子的相对表达量为研究因素,运用SPSS21.0统计软件包进行析因方差分析。结果随着盲肠结扎比例的增加,CLP脓毒症大鼠的死亡率上升,存活时间缩短,差异具有显著统计学意义(P0.05),同时IL-1α、TNF-α、IL-6表达水平均值逐渐升高;析因方差分析显示三种固定因素中盲肠结扎比例在三种细胞因子表达水平的主效应具有显著统计学差异(P0.05),穿刺针型号及抗生素使用情况的主效应无显著统计学意义(P0.05),盲肠结扎比例与抗生素使用情况两因素具有交互作用(P0.05)。结论盲肠结扎比例是CLP脓毒症大鼠模型死亡率及感染程度的重要决定因素,盲肠结扎比例与抗生素应用情况两因素间对细胞因子表达水平具有交互性作用。

Influence factors of severity in the establishment of CLP septic rat models by factorial desigh method

Objective To explore the influence factors of severity in the establishment of CLP septic rat models. Methods There were three investigated factors： the proportion of cecum ligation （25%, 50%, 75%）, the size of the puncture needles （12-gauge needle, 16-gauge needle） and the utilization of ceftriaxone sodium after postoperative. The experiment design was according to 3 × 2× 2 factorial experimental design,all ofthe 84 male Wistar rats were randomly divided in accordance with the random number tablein- to 14 groups to establish CLP rat models of sepsis,and the indexes were survival rate and the relative expression of IL-1α,TNF-α,IL-6 in liver after 24 hours. Statistical analysis was done by SPSS 21.0 software. Results Along with the increasing of the proportion of cecum ligation, the mortality ratein all the groups of sepsis increaseded and themean survival timegradually shortened with statistically significant difference （ P 〈0.05）;meanwhile, the mean expression level of IL-lα,TNF-α,IL-6 keeped increasing. ; The result of factorial analysis shows that the mean expression level of IL-lα,TNF-α,IL-6 showed significant difference with thechanging of the proportion of cecum ligation,neither of other two fixed factors：the size of the puncture needles and the utilization of ceftriaxone sodium after postoperative. What＇s more,the proportion of cecum ligation and the utilization of ceftriaxone sodium after postoperative had remarkable interaction to the expression of IL-lα,TNF-α,IL-6（ P 〈0.05 ）. Conclusion The proportion of cecum ligation isan important determinants of survival rate and severity of infection in septic rat models,The propor- tion of cecum ligation and the utilizationof ceftriaxone sodium exerts interactive effect in the expression of cytokines in liver of septic rat models.