Objective: To investigate the role of growth factors and their receptors in partial-thickness burn wound healing.
Methods: SD rats were used. After 10% total body surface area partial-thickness burn, wound tissues were harvested on postburn days (PBDs) 0(normal control), 1, 3, 5, 7, 10 and 14 respectively. The gene expressions of growth factors and their receptors were determined in wound by in situ hybridization and slot blotting hybridization. At the same time, the process of the wound healing was observed histologically, and the regeneration cycle of epidermal cells and the temporal change in inflammatory cells were measured.
Results: Inflammatory cells infiltrated into wound surface were neutrophils, followed by macrophages and lastly lymphocytes. Epidermal cells proliferated most actively on PBD 3 and the mitoses of them increased significantly on day 7 after burn. The gene expression of PDGF, PDGFR and EGFR reached peaks on PBD 1 and the gene expression of EGF and TGF beta-R2 were highest on PBD 3. In addition, the gene expression of TGF beta-R1 and TGF beta 1 increased significantly on PBDs 5 and 7 respectively.
Conclusion: The data suggested that burn can induce gene expression of EGF, PDGF, TGF-beta 1 and their receptors temporally, spatially, and reversibility, which might play a major role in burn wound healing, and the mutual regulation may exist in the gene expression and the cell cycle.