Abstract
The development of rachitis was observed on albino rats of Wistar strain which were resistant to vitamin D depletion. The development of rachitis was assessed from the width of the epiphyseal plate in radius and serum inorganic phosphorus level. Three weeks depletion period, which has been recommened for the line test, did not show clear evidence of rachitis in Wistar strain rats. Six weeks depletion period was shown to be suitable, namely, the width of the epiphyseal plate was widen to 1.50 mm and serum inorganic phosphorus level was reduced to 3.4 mg/dl. Therefore, the effects of vitamin D_3 and 1α-hydroxyvitamin D_3 (1α-OH- D_3) on the healing of rachitis were observed on Wistar strain rats which were raised on rachitogenic diet for 6 weeks. In good agreement with the findings of other investigators which Holzman strain rats were raised on rachitogenic diet for three weeks. 1α-OH-D_3 was more effective than vitamin D_3 for the healing of rachitis and the elevation of serum inorganic phosphorus level.
