Ethane 1-hydroxy-1, 1-diphosphonate (EHDP) counteracts the inhibitory effect of uranyl nitrate on bone formation

The beneficial effect of ethane 1-hydroxy-1, 1-diphosphonate (EHDP) in restoring the inhibition of bone formation in cases of acute uranium intoxication is presented. Bone formation was studied histomorphometrically in a model of alveolar bone healing. After tooth extraction, 40 rats were divided into 4 groups that received (1) no further treatment, (2) 10 daily intraperitoneal injections of 7.5 mg/kg of body weight of EHDP, (3) an intraperitoneal injection of 2.0 mg/kg of body weight of uranyl nitrate, and (4) the same treatment as was provided rats in groups 2 and 3. The results showed that the healing of bone did not occur in exposed animals, whereas healing in EHDP-treated exposed animals did not differ from that of nonexposed controls. This effect might result from a blocking and/or competitive action of EHDP and/or the stimulation that EHDP elicits at the doses and in the administration period studied.