Male Wistar rats aged 6 weeks corresponding to the school-childhood period in humans were used. A low calcium diet was given for 3 weeks, resulting in bone loss, and was then changed to a normal diet for another 3 weeks, in the low calcium diet control diet group. The low calcium diet was given for 3 weeks, resulting in bone loss, and was then changed to a normal diet containing Ipriflavone for another 3 weeks in the low calcium dietnormal calcium diet (Ipriflavone mixture) group. The effects on the metaphysis of the tibia were investigated.
The results were reported as follows.
1. Densitometry
The low calcium group showed a significantly lower density than the control group, and the low calcium normal diet groups (p<0.01). The group with the low calcium, normal diet containing Ipriflavone showed a higher dentisty than the low calcium normal diet groups (p<0.01).
2. Histopathologic findings
Compared with the low calcium diet normal diet groups, the low calcium diet normal diet groups (with the ipriflavone mixture) showed a decrease in the width of the chondrocytic layer, an increased calcified matrix and erosion, of this indicating advanced endochondral ossification.
Based on these results, it was found that if the bone mass is fully achieved with a normal diet in the school childhood, period even though bone loss is induced, the recovery of the bone formation can be achieved by the bone formation promoting action of Ipriflavone.