[Effects of WO-1 on repair of bone defects in rabbits]

To evaluate the effect of WO-1 on repair of the bone defect in the New Zealand rabbit radius by an oral or local administration.

Bone defects were surgically created in the bilateral radii of 36 Zealand rabbits (1.6-2.0 kg), which were randomly divided into 3 groups. In Group A, the defective areas were given WO-1 0.1 ml (50 mg/ml) by the local injections; in Group B, the rabbits were given WO-1 5 mg each day by the oral administration. Group C was used as a control group. Among each of the 3 groups, 4 rabbits were randomly selected and were sacrificed at 20, 30 and 60 days after operation, respectively. Then, the serological, X-ray and histological examinations were performed.

The serum alkaline phosphatase and bone gla-protein levels were significantly higher at 20 and 30 days after operation in Groups A and B than in Group C, but significantly lower at 60 days after operation in Groups A and B than in Group C(P<0. 01). The X-ray and histological examinations at 20, 30 and 60 days after operation revealed that the callus formation and remodeling were earlier in Groups A and B than in Group C, and the remodeling was earlier and better in Group A than in Group B.

WO-1 can promote the repair of the radial defect in a rabbit; however, further studies on the dose-effect relationship, administration time, and administration route are still needed.