OBJECTIVE: To observe the effect of chitosan/alginate (CTS/ALG) dressings on wound immersed in seawater. METHODS: Twenty-five healthy SD rats weighing 250-300 g were used to establish skin wound model through cutting 1.8 cm circle-shaped wound along spine bilaterally. The left side served as experimental group, and the right side as control group. The wounds were immersed in the prepared artificial seawater for 1 hour, then the experimental group was treated with CTS/ALG dressings, while the control group was treated with sterile gauze. Gross observation was performed and wound healing time was recorded. At 3, 5, 7, 10 and 12 days after operation, 2 cm x 2 cm skin tissues including the wounds were removed and underwent HE staining and immunohistochemistry staining using Envision method. Histological change of wound and expression of EGF receptor (EGFR) and bFGF were observed. RESULTS: In the experimental group, wound inflammatory response was slight and incrustation shrinked faster, while the incrustation in the control group shrinked slowly. The wound healing time of the experimental group and the control group was (11.68 +/- 0.57) and (12.51 +/- 0.54) days, respectively, suggesting there was a significant difference between two groups (P < 0.05). In the experimental group, granulation tissue proliferation, cell infiltration, collagen tissue proliferation, wound shrinkage and epithelization appeared at 3 days after operation; regularly lined collagen tissue, complete epithelization and occurrence of skin appendages were observed at 10 days after operation; complete wound healing was noted at 12 days after operation; while in the control group, at the corresponding time point, late cell infiltration and epithelization were observed and granulation tissue with ulcer was noted. Immunohistochemistry observation: high expression of bFGF in vascular endothelial cells and interstitial fibroblasts and high expression of EGFR in vascular endothelial cells were observed in the experimental group at 3 and 5 days after operation, and their expressions were low at 7, 10 and 12 days after operation; while in the control group, there were no or low expression of bFGF and EGFR at the same time point. CONCLUSION: CTS/ALG dressings can promote the healing of wound immersed in seawater, but its mechanism needs further study.
OBJECTIVE: To observe the effect of chitosan/alginate (CTS/ALG) dressings on wound immersed in seawater. METHODS: Twenty-five healthy SD rats weighing 250-300 g were used to establish skin wound model through cutting 1.8 cm circle-shaped wound along spine bilaterally. The left side served as experimental group, and the right side as control group. The wounds were immersed in the prepared artificial seawater for 1 hour, then the experimental group was treated with CTS/ALG dressings, while the control group was treated with sterile gauze. Gross observation was performed and wound healing time was recorded. At 3, 5, 7, 10 and 12 days after operation, 2 cm x 2 cm skin tissues including the wounds were removed and underwent HE staining and immunohistochemistry staining using Envision method. Histological change of wound and expression of EGF receptor (EGFR) and bFGF were observed. RESULTS: In the experimental group, wound inflammatory response was slight and incrustation shrinked faster, while the incrustation in the control group shrinked slowly. The wound healing time of the experimental group and the control group was (11.68 +/- 0.57) and (12.51 +/- 0.54) days, respectively, suggesting there was a significant difference between two groups (P < 0.05). In the experimental group, granulation tissue proliferation, cell infiltration, collagen tissue proliferation, wound shrinkage and epithelization appeared at 3 days after operation; regularly lined collagen tissue, complete epithelization and occurrence of skin appendages were observed at 10 days after operation; complete wound healing was noted at 12 days after operation; while in the control group, at the corresponding time point, late cell infiltration and epithelization were observed and granulation tissue with ulcer was noted. Immunohistochemistry observation: high expression of bFGF in vascular endothelial cells and interstitial fibroblasts and high expression of EGFR in vascular endothelial cells were observed in the experimental group at 3 and 5 days after operation, and their expressions were low at 7, 10 and 12 days after operation; while in the control group, there were no or low expression of bFGF and EGFR at the same time point. CONCLUSION: CTS/ALG dressings can promote the healing of wound immersed in seawater, but its mechanism needs further study.