ABSTRACT
This study was designed to compare skin wound healing in three groups of Wistar rats: normal, genetically diabetic, and streptozotocin-induced diabetic. All diabetic animals received daily insulin. Full-thickness midline dorsal skin wounds were analyzed biomechanically for strength, toughness, and elasticity (Young's modulus) at 1 and 3 weeks after wounding. Wounds from normal controls were the strongest, toughest, and least compliant. Genetically diabetic rat wounds were the weakest and had the lowest elastic modulus. Wounds from the streptozotocin-induced rats were intermediate for all parameters measured (ANOVA, p = 0.001). Toxin-induced diabetes is less detrimental to skin wound healing than diabetes of endogenous origin. Whether this is due to basic differences in the models or to differences in duration of diabetes is unknown.
Subject(s)
Diabetes Mellitus, Experimental/physiopathology , Skin/physiopathology , Wound Healing , Animals , Biomechanical Phenomena , Diabetes Mellitus, Experimental/chemically induced , Rats , Rats, Wistar , Skin/injuries , StreptozocinABSTRACT
This study was designed to evaluate biomechanically defined wound healing in full-thickness skin explants in tissue culture. The requirement for preculture incubation of wounds in situ was characterized. Full-thickness skin incisions were made in 44 rats and closed immediately. Wounds were incubated in situ for 0, 12, 24, 36, 48, 72, or 96 hours before harvesting and placement into tissue culture media for 6 weeks. Healing was evaluated by biomechanical criteria: tensiometric distraction to wound rupture generated true stress and energy absorption data. Burst-strength (maximum true stress) and toughness (energy absorption) were five times higher in the 48-hour group than in any other group; other groups were not different from each other. This study demonstrates long-term survival of full-thickness skin in culture and shows that full-thickness skin explants heal in tissue culture. Possible explanations for the narrow window of opportunity for harvest (48 hours, no more and no less) are discussed.