模拟绞窄性肠梗阻发展过程的大鼠模型的建立

Establishing the Strangulated Intestinal Obstruction Model in Rats

目的建立一种可以模拟绞窄性肠梗阻发展过程的大鼠模型,要求肠管的损伤程度呈现出较明显的时间相关性和同步性。方法选取成年健康雄性Sprague-Dawley大鼠,制作腹壁嵌顿疝模型。模型中腹壁缺损的长度(疝环的半周长)为待嵌顿肠管管径的80%,将长度为6cm的选定肠管自腹壁缺损处脱出埋置于皮下,形成腹壁嵌顿疝,模拟绞窄性肠梗阻。根据肠管嵌顿时间的增加,依次将模型分为六组,嵌顿时间自1h起,每组依次增加1h,最长为6h,设置假手术对照组。通过光镜下病理检查,确定肠管损伤程度并根据肠管坏死的程度进行分级,应用Ritid分析比较各组之间肠管损伤程度的差异。结果与对照组比较,各实验组均呈现不同程度的肠管损伤。经过Ritid分析,对照组肠管损伤分级的平均Ritid值为0.038,各实验组依嵌顿时间递增排序,自嵌顿1h组至嵌顿6h组,各组肠管损伤分级的平均Ritid值依次为0.248、0.329、0.464、0.551、0.765和0.874。通过方差分析中的LSD两两检验,可以看到各实验组与对照组相比,肠管损伤程度均存在明显差异,P值均小于0.035;各实验组间,嵌顿时间相差2h及以上者,肠管损伤程度均存在明显差异,P值均小于0.01;嵌顿4h与5h组间,肠管损伤程度存在明显差异,P=0.01,余嵌顿时间相差1h的各实验组间,肠管损伤程度无明显差异,P值均大于0.09。结论本实验制备的大鼠腹壁嵌顿疝模型较好地模拟了绞窄性肠梗阻的发展过程,随着嵌顿时间的延长,肠管损伤程度渐进性加重;相近的嵌顿时间,肠管的损伤程度无明显差别;肠管的损伤程度呈现出较明显的时间相关性及同步性。

Objective To establish a rat model of strangulated intestinal obstruction,which can present good time-dependent relation and unification between the intestinal incarceration time and the degree of intestinal necrosis. Methods By choosing adult healthy male Spraque-Dawley rats,an incarceration hernia model to imitate the strangulated intestinal obstruction was made. In the incarceration hernia model,a midline fascial defect was made,the length of the defect was set by the 80 percent of the diameter of incarceration bowel,and the length of incarceration bowel was 6 cm. All rats were divided into six groups by different intestinal incarceration time,from 1 hour to 6 hours step by 1 hour. With the sham operation group as the contral group,the grade of intestinal injury between the groups was compared by necrosis degrees under microscopy,and the statistic method was ritid analysis. Results Comparing with the control group,the different degree of intestinal necrosis was found,the longer intestinal incarceration time and the higher degree of intestinal necrosis. But with the same intestinal incarceration time,the degree of intestinal necrosis was similar. The mean ritid value of control group was 0. 038; the mean ritid value of each experimental group from 1 hour to 6 hours was 0. 248,0. 329,0. 464,0. 551,0. 765 and 0. 874,respectively. Using LSD test of analysis of variance,microscopic intestinal injury in each eaperimental group was significantly different from the control group（P 0. 035）; the significantly difference of intestinal injury was found between the experimental groups,which difference of intestinal incarceration time was 2 hours or more（P 0. 09）; no significantly difference of intestinal injury was found between the experiment groups,which difference of intestinal incarceration time was 1 hours,except for the 4 hours group and 5 hours group（P = 0. 01）. Conclusion A rat model of strangulated intestinal obstruction has been established,which can present good time-dependent relation and unification between the intestinal incarceration time and the degree of intestinal injury.