Abstract: Measurement of calrnoduliu (CaM) was made with microspectrophotometer in psoriatic dispersed epidermal basal cells. Fluorescence from total CaM was induced by anti-CaM-FITC and that from activated CaM was induced by its antaguoist trifluoperazine(TFP). The results showed that both CaM and active. ted CaM were siginificantly higher in psoriatic basal oelis (10 patients) than normal controls.Level of totxl CaM in the uninvolved basal cells was also elevated but to a lesser degree. Sut the activated CaM in uninvolved skin showed no significant difference with normal control. Meanwhile, total CaM and activated CaM in both normal and diseased cells were increased from G₁ through S to C₂M.