| Abstrakt: |
Standard wounds of approximately 17 mm.2 area have been made in the dorsolumbar region of rats by cutting out a small square of skin within a standard tattoo-mark. By this technique, at 5, 10, 15, and 25 days after operation, the amount of wound contraction (disregarding epithelialization) has been measured, and the area of repair has been removed for collagen estimation by the hydroxyproline method of Neuman & Logan (1950). Contraction had occurred significantly 5 days after operation, was very active between 5 and 10 days, and did not proceed farther after 10 days. There was a decrease in wet weight of the wound content parallel to its contraction in area. During contraction the wound changed in shape from a square to a 4-pointed star. The rim of old tissue surrounding the wound diminished in length and in area. When contraction had ceased the surrounding skin was under abnormal tension, judged by the expansion when the wounded area,was excised. These observations can be accounted for by supposing that the content of the wounded area exerts a contractile force, and that the rim of original skin has some rigidity. Chemically measurable collagen formation had started 5 days after operation and it continued beyond 10 days, i.e. after contraction had ceased. The result was a progressive rise in both concentration and absolute amount of collagen in the wound. By 25 days the area under repair was, however, not nearly back to normal in collagen per unit area or per unit wet weight. |
