Abstract: Objective To investigate the mechanism of effects of acitretin on the treatment of psoriasis. Methods The expression of vascular endothelial growth factor (VEGF) and micro-vascular density (MVD) were detected by immunohistochemical technique before and after treatment with acitretin in 32 patients with psoriasis. Serum level of VEGF was measured by double antibody sandwich enzyme-linked immunosorbent assay (ELISA). Results The expression of VEGF protein and MVD were significantly higher in psoriatic lesions before treatment with acitretin than those after treatment (P<0.05) and those in the normal controls (P<0.001). Conclusions VEGF plays an important role in the angiogenesis of psoriasis, which indicates that anti-angiogenesis may be involved in the mechanism of effects of acitretin on the treatment of psoriasis.

Key words: Acitretin, Psoriasis, Endothelial growth factors, Neovascularization, pathologic, Micro-vascular density