Establishment of rat intermittent and persistent hypoxia skin expansion model

CUI Jiang-bo; LEI Lei; YU Zhou; DING Jian-ke; ZHANG Yu; LIU Heng-xin; MA Xian-jie; SU Ying-jun

doi:10.3969/j.issn.1673-7040.2018.05.012

Abstract：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 (tcpO2) 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 (HypoxyprobTM-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.