Simple method of open skin wound healing model in corticosteroid-treated and diabetic rats: standardization of semi-quantitative and quantitative histological assessments

The use of a simple and reproducible model is inevitable for objective statement of the effects of external factors on wound healing. Hence, present study was conducted to establish an excisional model of skin wound healing in corticosteroid treated, and streptozotocine induced diabetic rats as well as to standardized the semi-quantitative and quantitative evaluation of selected parameters. Round full thickness skin wounds were performed on the back of male Sprague-Dawley rats. Animals were sacrificed two, six, and fourteen days after surgery. Sections were stained with hematoxylin-eosin and van Gieson. Both semi-quantitative (wound reepithelization; presence of: inflammatory cells, fibroblasts, new wessels, and collagen) and quantitative methods (polymorphonuclear leucocytes/tissue macrophages ratio, percentage of re-epithelization, area of the granulation tissue) were used to evaluate the histological changes during wound healing. As compared to the control group the wound healing process of both experimental groups was decelerated. Interestingly, wound reepithelization and angiogenesis were significantly inhibited only in the steroid rats while epithelization was accelerated in diabetic rats. In conclusion, when compared to primary sutured wound healing it can be concluded that the excisional model is more appropriate for histological assessment of the effect of various factors on wound healing. In addition, administration of corticosteroids represents simple and inexpensive model of a complex skin wound healing impairment.