“…Daily administration of 1,25(OH)2-vitamin-D3 (1)(2)(3)(4) jug/kg body weight) or of 10000 units of 25(OH)-vitamin-D3 result in clinical healing. These results suggest a defective renal 1-hydroxylase as the primary defect of this animal model (Harmeyer & Plonait, 1967;Meyer & Plonait, 1968;Plonait, 1969;Harmeyer, Martens & Vogelsang, 1975;Wilke, Harmeyer, von Grabe, Hehrmann & Hesch, 1979;Winkler, Schreiner & Harmeyer, 1986).…”