大鼠间断及持续缺氧皮肤扩张模型的构建

Establishment of rat intermittent and persistent hypoxia skin expansion model

目的构建大鼠背部间断缺氧及持续缺氧皮肤软组织扩张模型,为皮肤软组织扩张术的基础研究提供稳定的动物模型。方法将24只体质量200~250g SD大鼠分为持续缺氧扩张组和间断缺氧扩张组,每组12只;在每只大鼠背部近尾端置入1枚10 ml皮肤软组织扩张器。两组在扩张过程中监测经皮氧分压,通过注水调节,维持扩张皮肤处于持续或间断缺氧状态。扩张结束后采集各组扩张区域中央皮肤组织样本行HE染色,并在镜下观察皮肤结构的变化,计数毛囊;应用CD31免疫组织化学染色行血管计数;应用组织缺氧探针(hypoxyprob^(TM)-1)免疫荧光染色,对各组真皮层缺氧的成纤维细胞及总成纤维细胞计数,计算缺氧细胞比率。结果镜下观察组织切片可见持续和间断缺氧组扩张后的表皮层较正常皮肤明显增厚,真皮层均变薄;间断缺氧及持续缺氧扩张组的表皮厚度较正常皮肤明显增厚,血管密度明显增加;持续缺氧组较间断缺氧组的真皮层成纤维细胞缺氧探针表达的阳性率高。结论成功构建了大鼠背部间断及持续缺氧皮肤软组织扩张模型,其具有良好的稳定性及可重复性。

Objective To establish a skin soft tissue expansion model for rat dorsum intermittent and persistent hypoxia and provide a stable animal model for the basic research of skin and soft tissue dilatation. Methods Twenty-four Sprague-Dawley Rats weighing from 200 to 250 grams, were divided into 2 groups： the persistent hypoxia group（PH） and the intermittent hypoxia group（IH）, with 12 rats in each group. A skin soft tissue expander of 10 ml was subcutaneously implanted near the tail of each rat dorsum. The expanders in the PH and IH groups received saline injection daily and the transcutaneous oxygen pressure（tcp O2） of the expanded skin was monitored during the expansion process. The skin samples in the center of the expanding region in each group were collected, fixed, embedded in paraffin,sectioned, and stained with HE. The hair follicle was counted. The microvascular count was obtained through CD31 immunohistochemical staining. The state of hypoxia in the tissue was quantitatively determined with immunofluorescent staining of a hypoxia-specific probe（Hypoxyprob-（TM）-1） in the pre-treated skin tissues. The ratio of anoxic cells was calculated. Results Compared with normal skin, the epidermal layer of the expanded region was significantly thickened and the dermis layer was thinned in IH and PH groups. More dermal hypoxic fibroblasts were found in PH group than in the IH group. Microvascular density was significantly increased in both the PH and IH groups. In the PH group, the positive rate of hypoxia probe expression in dermal fibroblasts was higher than that in the IH group. Conclusion The intermittent and persistent hypoxia skin soft tissue expansion model of a rat dorsum was successfully established. It has good stability and repeatability.