The objectives of this proposal are to identify the collagen makeup of hypertrophic scars and explore new ways to effectively control scar formation. The identification of collagen types within scar has been greatly facilitated by a newly developed technique which has been named Zone Chromatography. It can quickly separate native collagens into their various genetically distinctive types. At present we have identified and quantitated 5 collagen types in hypertrophic scar: Type I, Type III, Type I trimer, Types A-B collagens. The use of antimitotic agents as inhibitors of scar formation have been investigated in the rat model system. Colchicine which can modify healing in rabbits, is not effective in rats; but vinblastine is effective and retards wound healing and new collagen synthesis. Using the rat healing model, it has been found that frozen injuries heal without contraction; while burns rely upon contraction for healing. The cellular and matrix components of freeze and burn injuries are currently being examined and compared. Preliminary evidence suggests that the cellular makeup of both forms of trauma are similar but the connective tissue matrix is different. In general injuries heal like full thickness grafted wounds, while burn wounds heal like open wounds.