CLODRONATE PREVENTS IMMOBILIZATION OSTEOPENIA IN RATS

We investigated the effect of clodronate on immobilization osteopenia (IO) induced by sciatic neurectomy in rats. 100 Wistar female rats wer e divided into 5 groups of 20 animals each: 1) sham-operated, control group, 2) IO + saline control group, 3) IO + clodronate 3 mg/kg/day, 4 ) IO + clodronate 10 mg/kg/day, and 5) IO + clodronate 30 mg/kg/day. C lodronate was administered subcutaneously beginning on the day after n erve sectioning. After 7 weeks, the animals were killed and both tibia e were removed. Bone mineral density, ash weight and calcium, phosphor us and magnesium contents of the ash of the tibiae were analyzed. The weight of the rats did not differ between the groups during the experi ment. The ash weight of the tibiae decreased by 6.6 percent and the mi neral density decreased by 5.1 percent after neurectomy. Clodronate re duced IO in a dose-dependent manner and the highest dose neutralized t he effect of neurectomy. The calcium content of the ash decreased afte r neurectomy as compared to the sham-operated group, and clodronate in creased it to the sham-operated level. The bone Ca/P ratio remained no rmal.