Wound healing process of a full-thickness skin wound model in rats.

Using a rat full-thickness skin wound model, confocal laser scanning microscopy was carried out for examination of angiogenesis in granulation tissue formation. By semi-quantitation analysis with reverse transcription-polymerase chain reaction (RT-PCR), assessment was made of mRNA expression in the vascular endothelial growth factor (VEGF) and connective tissue growth factor (CTGF). Immunohistological analysis was also made to determine the location of these factors in granulation tissue at the protein level. Comparison was made of the cytokines in granulation and angiogenesis. Chronic granulation tissue with advanced fibrosis could be clearly demonstrated by the inhibition of wound contraction and epithelialization. From the results of the present study, VEGF would appear quite closely involved in angiogenesis in granulation tissue formation and pericytes may possibly give rise to VEGF and have significant roles in angiogenesis even with inhibition of epithelialization. CTGF expression in parenchyma is considerable during granulation and thus possibly may be related to the progress of fibrosis.