浅Ⅱ度烫伤复合机械力牵拉刺激动物模型的建立及评估

A novel mechanical stretch model in mice with superficial second degree burn

目的建立浅Ⅱ度烫伤复合机械力牵拉刺激动物模型,并对模型的稳定性、可靠性进行评估。方法选用10~12周C57BL/6小鼠60只进行实验。实验分为A组(浅Ⅱ度烫伤+机械力牵拉组)、B组(浅Ⅱ度烫伤+假手术对照组)和C组(正常对照组)。A组、B组根据不同取材时间(0、1、3、5、7、14d及21d)分为A1~A7亚组和B1~B7亚组。将小鼠编号并随机分到A1~A7亚组、B1~B7亚组和C组,每组4只小鼠。备皮后,用YLS-5Q台式恒温烫伤仪分别在A组、B组小鼠背部L1水平建立2cm2浅Ⅱ度烫伤创面,并利用组织缺损缝合的方法在A组小鼠上建立机械力牵拉刺激。分别在制创后的0、1、3、5、7、14及21d,取A组、B组小鼠的烫伤创面及C组相同部位的皮肤标本,进行病理学评估。结果成功建立了A、B组动物模型;病理分析可见A组烫伤创面痂下愈合速度较B组快;在烫伤后第1天,A组烫伤创面显著大于B组;在烫伤后第5、7和第14天,A组残余面积显著小于B组(P<0.05),且标准差0.01~0.15,说明张力控制方法至少可持续至建模第14天,且稳定可靠、可重复性好,能再现张力对创面的作用规律。结论本研究成功建立了一种简单、科学的小鼠背部浅Ⅱ度烫伤复合机械力牵拉刺激动物模型,为研究张力对烫伤创面愈合的影响奠定了基础。

Objective To establish a novel mechanical stretch model in mice with superficial second de- gree bums,and to evaluate the stability and reliability of the model. Methods Sixty C57BL/6 mice aged 10 - 12 weeks were selected and randomly divided into 3 groups,including group A （ mechanical stretch ＆ superficial second degree bums ） , group B （ sham operation ＆ superficial second degree bums ） and group C （ normal ）. Seven sub- groups were set separately in group A and B according to different time points, with 4 mice in each group. After the skin was prepared, a 2 cm2 area of superficial second degree bum wound was established on mice back in group A and B at L1 level using YLS-5Q Desktop Scald Thermostatic Instrument. And the mechanical stretch was established on each mouse in group A by tissue defect suture method. The bum wound samples were taken for pathologic evalu- ation at 0,1,3,5,7,14d and 21d in group A and group B,as well as the skin in the same site of mice in group C. Results Superficial second degree burns were successfully built. According to pathologic evaluation results, the healing rate of wound in group A was significantly faster than that in group B. Group A had significantly larger wounds at 1 d but had significantly smaller residual area at 5,7,14d than group B （ P 〈 0.05 ）. The standard devia- tion was between 0.01 and 0. 15, indicating that a stable and reliable mechanical stretch was sustainable until at least modeling day 14. Conclusion This study has successfully established a simple and scientific animal model of mechanical stretch stimulation with superficial second degree bum, which provides possible basis for studying the role of tension in scald wound.