Effects of low concentration 5-fluorouracil and triamcinolone acetonide on ear hypertrophic scar in a rat model

Abstract

Objective To explore the effect of low concentration 5-fluorouracil combined with triamcinolone acetonide on rabbit ear hypertrophic scar model. Methods White rabbits post-traumatic scars were randomly divided into A , B , C and D groups, each group contained 18 cases. Group A was given triamcinolone acetonide and low concentration 5-fluorouracil, Group B was given low concentration 5 - fluorouracil, Group C was given triamcinolone acetonide and Group D was used as the control group. The dynamic changes of the scar were observed by naked eyes, hematoxylin-eosin (HE) staining and van Gieson (VG) staining through microscope. Vascular endothelial growth factor (VEGF) and CD34 were detected and compared within 4 groups by immunohistochemical staining. Results We successfully established a rabbit ear scar model. It was observed that the scars of Groups A, B and C had been shorter and flatter than Group D, close to the normal tissue. In HE and VG staining, the number of fibroblasts, inflammatory cells, blood vessels in groups A, B and C had been decreased, compared with Group D. Immunohistochemical results showed that the positive rates of VEGF and CD34 from the most to the lest were Groups D, B, C and A. The scar proliferation index from the most to the lest were Groups D, B, C and A. Conclusions The effect of low concentration 5-fluorouracil in treatment of the rabbit ear hypertrophic scar is better than that of triamcinolone acetonide. Low concentration 5-fluorouracil combined with triamcinolone acetonide has a synergistic effect in treatment of hypertrophic scar, which has better effect than that of low concentration 5-fluorouracil or triamcinolone acetonide alone. Key words: Hypertrophic scar; 5-fluorouracil; Triamcinolone acetonide; Vascular endothelial growth factor; CD34