Anais Brasileiros de Dermatologia
On-line version ISSN 1806-4841
TENIUS, Fernando Pundek; BIONDO-SIMOES, Maria de Lourdes Pessole and IOSHII, Sérgio Ossamu. Effects of chronic use of dexamethasone on cutaneous wound healing in rats. An. Bras. Dermatol. [online]. 2007, vol.82, n.2, pp. 141-149. ISSN 1806-4841. http://dx.doi.org/10.1590/S0365-05962007000200005.
BACKGROUND: Glucocorticoids are believed to hinder healing process, causing decreased cell proliferation, neovascularization and matrix production. OBJECTIVE: To investigate the effects of the chronic use of corticosteroids on skin wound healing. METHODS: After daily injections of dexamethasone (0.1 mg/Kg) for 30 days, an excision was made in the dorsum of rats. Wound healing was evaluated at postoperative days 3, 7 and 14. Scar resistance, collagen density and inflammatory reaction were assessed by histometry. RESULTS: The scars of the dexamethasone-treated group were less resistant to traction in all days (p=0.008) and presented lower collagen density. Collagen III density was affected at all times (p<0.0001) and collagen I density was lower only on day 14 (p<0.0001). The inflammatory cell infiltration was less intense in the dexamethasone-treated group in the first two evaluations (p=0.001 and p=0.016), but there was no significant difference on day 14, (p=0.367). CONCLUSIONS: We observed decreased scar resistance and lower total collagen density in all periods studied. In the beginning of the process, low collagen III density was observed and later collagen type I density was also decreased. Reduced number of inflammatory cells was found in the first two evaluations.
Keywords : Collagen; Dexamethasone; Wound healing.