A Mouse Model of Scald Wounds

Background: There were many mouse models of scald wounds have been created in the previous study. However, expensive materials, complicated and dangerous operation and poor repeatability were all disadvantages of most of these models. The purpose of this study was to establish a mouse model of scald wounds with controllable depth and area using some common consumables in the laboratory. Materials and Methods: A homemade scald-producing device was produced in our laboratory by using some common consumables, including 50ml centrifuge tube, water bath kettle, thermometer etc. Twelve male C57BL/6 mice were randomly divided into two groups (n=6 in each group). Mice in control group were not burned. Mice in experiment group were scalded with hot water. More specifically, the mice in experiment group were fixed into the home-made fixture device, allowing the shaved dorsum expose to 90°C water for 9s. 24h later, skin samples of all mice in two groups were harvested for histopathological examination (H&E), masson staining and CD31 Immunohistochemistry assay. Terminal-Deoxynucleoitidyl Transferase Mediated Nick End Labeling (TUNEL) assay was performed to detect the apoptosis of scald wound. Results: This mouse model of full-thickness scald injury could be produced successfully by scalding with 90°C hot water for 9s. At 24h after scald, the skin tissues of mice in the experiment group exhibited the fractured and necrotic epidermal layer away from dermal layer, with almost unviable dermal hair follicles. Amounts of collagen degeneration, blood vessels necrosis and lots of increased apoptotic cells were demonstrated in scald skin. In addition, compared with the control group, coagulation necrosis and homogenization change of partial subcutaneous adipose tissue were observed in the scald skin. And even the superficial portion of some intradermal muscle layer was injured. The above experiments were repeated three times. The mouse model of scald wounds was successfully produced every time. The depth and area of burn were controllable. The model possessed a great repeatability. Conclusions: These results indicated that the homemade scald-producing device could be successfully and conveniently used for producing the mouse model of scald wounds. Simple structures, low cost, transparent fixture device for easy observation and safe operation are all its advantages. Much more important, the depth and area are controllable through precise temperature control and standardized animal positioning.