RESUMEN
Wounds on the limbs of horses are notoriously difficult to heal, with over production of TGFß1 thought to be responsible for excessive scarring; in contrast, wounds in the oral cavity heal rapidly with minimal scarring. This experiment aimed to determine the effect of TGFß1 on the production of mRNA and proteins for various extracellular matrix components by two equine fibroblast cell lines isolated from the oral mucosa and distal limb. Fibronectin mRNA was up-regulated by TGFß1 in the limb but not the oral cells. TGFß1 increased the ratio of mRNA for collagen types I-III for the oral cells only. mRNA expression for TGFß receptors-I and -II was significantly lower in limb fibroblasts, and treatment of either cell line with TGFß1 down-regulated mRNA expression for both receptors. These differences may account for the improved healing seen in oral wounds compared to the excessive scarring seen in limb wounds.