Ultrastructure of murine dermis following topical application of the vitamin D3 analogue KH-1060
The aim of this study, was to observe the effects of KH-1060, a new vitamin D3 analogue, on the dermis of hairless mice by electron microscopy. KH-1060 (0.2 micrograms/ml in isopropanol) or KH-1060 following betamethasone 17-valerate (2 mg/ml in isopropanol) was applied topically to the backs of hairless mice for 4 weeks. KH-1060 increased the number of dermal fibroblasts, the cytoplasm of which was dominated by secretory components. Mast cells contained normal mature granules and degranulated after disintegration. No extrusion of non-disintegrated granules was seen. Collagen fibrils were thickened and increased in number; however the content of type I collagen in the fibrils did not increase. Glycosaminoglycan figures appeared distinct. KH-1060 prevents betamethasone-induced changes in collagen fibrils and glycosaminoglycans, while no prevention was seen for mast cells.