[Effects of vanadyl sulfate on osteopenia in streptozotocin-induced diabetic (STZD) rats. Comparison with those of insulin].

The insulin mimetic effects of vanadium salts on glucose metabolism have been well-documented in STZD rats. In this study, the long-term effects of vanadyl sulfate (vanadium) on osteopenia in STZD rats were examined and compared with those of insulin. From 2 days after an intravenous injection of streptozotocin (30 mg/kg), the rats with hyperglycemia (> 300 mg/dl) received either vanadium (0, 0.02, 0.1 or 0.5 mg/ml) in drinking water or daily subcutaneous injections of insulin (0, 0.4 or 4.0 U/day) for 54 days. Their tibiae and femurs were examined by chemical analyses, by contact microradiography and by the method of double tetracycline labeling. Decreases in bone mass, bone density and in the rate of bone formation were observed in STZD rats. Development of these symptoms in the STZD rats with osteopenia was prevented by the administration of either vanadium or insulin in a dose-dependent fashion. The effects of vanadium at a dose of 0.5 mg/ml for preventing bone loss in STZD rats were similar to those of insulin at a dose of 4.0 U/day. These results indicate that vanadium has insulin mimetic effects on osteopenia in STZD rats.