Effects of chondroitinase on hypertrophic scar in rabbit ears

Objective To investigate the effects of chondroitinase on the formation of hypertrophic scar in rabbit ears. Methods Wound-healing models were established on ears of 12 healthy the Jepanes rabbits, which were randomly divided into the collagenase-treated group (group A), the chondroitinase ABC and collagenase -treated group (group B), the chondroitinase ABC-treated group (group C) and saline-treated group (group D ). Compound staining was used to observe the morphological and histological changes in hypertrophic scar. Image analysis technique and chemical way were employed to measure the contents of collagen and hydroxyproline. Results It was found that the colour of the acid mucopolysaccharide in each control group was turned into pale blue, the collagen fibers in hypertrophic scar arranged sparsely and destroyed greatly according to compound staining. Hydroxyproline content of the A, B, C and D were significantly different as time went by (P0.05). Compared with group A and C, hydroxyproline content of group B had significant difference on the 28th day (P0.05), and there was significant difference on the 35th day between group B and group A (P0.05), the hydroxyproline content of group B was much lower than those of other groups after two weeks′ treating (P0.05). Conclusion Chondroitinase A, B, C increase the degradation of collagen fibers after removing the acid mucopolysaccharide around the collagen fibers. This may provide a new way on hypertrophic scar treatment.