热应激预处理缩短皮管断蒂时间的实验研究

Heat stress pretreatment shortening amputation time of tube skin flap in dogs

目的:探讨热应激预处理对皮管的保护作用以及缩短皮管断蒂时间的可行性。方法:以Labrador犬为实验对象建立动物模型,行双侧下腹部皮管成形术,分为实验侧和对照侧进行自身对照,术后用红外线热疗仪对实验侧皮管局部加温进行热应激预处理,再分别延迟0 h、24 h、48 h、72 h、1周、2周皮管断蒂,对照侧皮管未经热应激预处理直接断蒂,每一时间段组各4只动物,断蒂7 d后观测比较两侧皮管存活情况,并用免疫组化ABC法观察两侧皮管组织中热休克蛋白70(heat shockprotein 70,HSP70)的相应动态变化。结果:实验侧皮管组织内HSP70表达阳性,以热应激预处理后延迟24 h及48 h断蒂皮管的表达最强,对照侧则均呈阴性;24 h、48 h、72 h、1周和2周各时段,热应激预处理侧(实验侧)的皮管存活率大于对照侧,两者差异有统计学意义(P<0.05)。结论:热应激预处理对皮管具有保护作用,能够提高皮管断蒂以后的存活率,缩短皮管断蒂时间,其机制可能与热应激预处理后皮管HSP70的诱导合成有关。

Objective:To explore the protective effect of heat stress pretreatment on tubal flap and its feasibility to shorten the pedicle amputation time of tubed flap.Methods: Twenty-four adult Labrador dogs were selected to establish the animal model with hypogastric tubed skin flaps being prepared below two ventral sides. The experimental lateral tube flaps received heat stress pretreatment before amputating the pedicle at different time points (0 h, 24 h, 48 h, 72 h, 1 w, 2 w), whereas the pedicles of the control lateral flaps were amputated without heat stress pretreatment. The surviving length of the tube flaps and their HSP 70 expression were observed and compared 7 d after pedicle amputation. Results: In all experimental tube flap tissues, stress conditioning induced marked HSP 70 expression, especially in those of 24 h and 48 h group,while the HSP 70 expression in control lateral flaps was negative. There was an overall statistical significant difference of flap survival between the heat stress pretreated flaps (0 h, 24 h, 48 h, 72 h, 1 w, 2 w) and the controls(P<0.05).Conclusion: Heat stress pretreatment plays a protective role in tubed skin flap. It can improve flap survival after pedicle amputation and shorten the amputation time of tubed skin flap,which may be related to HSP 70 inducement and synthesis.