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wounds on the ears of 47 rabbits were created including rounds 6 mm in diamiter on ventrol or dorsal side and 1.5 cm x 4.5 cm rectangular
wounds. Histological and histochemical analyses, in situ hybridization and cell apoptosis were tested.
RESULTS: 70 percent of the
wounds can from excess dermal
scarring which is similar to human
hypertrophic scar. The hight of excess dermal
scarring is as 3-4 times high as original
ventol skin. The excess
scarring can last 150 days at the most. while 80 percent appears on rectangular
wounds and it lasts more than 262 days. Large amount of fibroblasts, nodular and spiral structures exist in excessive dermal
scarring. Local injection of
TGF-beta 1 and IFN-r can promote and inhibit the formation of excessive dermal
scarring respectively. SDS-PAGE shows that
type III collagen content increased in excessive dermal
scarring. In situ hybridization shows long-lasting expression of type I and III precollagen
mRNA in excessive dermal scarrint.
TGF-beta 1 mRNA also cope with that of precollagen. Fibroblast apoptosis in excessive dermal
scarring of this model indicate that fibroblast apoptosis plays an important role in the process of occurrance, development of abnormal
scar.
CONCLUSION: After wounding, rabbit ears can produce excessive dermal
scarring which is similar to human
hypertrophic scar. This can be used as an experimental model for the study of
cicatrix.