TACALCITOL (1,24(OH)(2)D-3, TV-02) INHIBITS PHORBOL ESTER-INDUCED EPIDERMAL PROLIFERATION AND CUTANEOUS INFLAMMATION, AND INDUCES EPIDERMALDIFFERENTIATION IN MICE

In this study, we examined the cutanaeous effects of tacalcitol [1, 24 (R)(OH)(2)D-3] on epidermal proliferation, differentiation, and skin i nflammation in vivo using hairless mice. Tacalcitol was shown to inhib it epidermal proliferation using TPA-induced ornithine decarboxylase a ctivity and DNA synthesis as indices, and the induction of epidermal d ifferentiation using type I transglutaminase activity as an index. Tac alcitol also displayed an antiinflammatory effect on TPA-induced infla mmatory changes histopathologically. These results confirm the clinica l efficacy of tacalcitol in psoriasis, and suggest that it may be effi cacious in the treatment of other inflammatory skin diseases.