[Experimental study of antagonizing effect of calcium and magnesium against fluoride toxicity in collagen].

SD rats were given fluoride 20 mg/kg for 14 days through a gastrointestinal tube, body weight growth depressed obviously, the ratio of the Liver and Kidney weight to body weight increased significantly, hemoglobin concentration dropped and morphology and metabolism of collagen all became abnormal. All these effects can be antagonised by giving calcium (100 mg/kg), magnesium (100 mg/kg) or calcium and magnesium combined (50 mg/kg each). When Ca and Mg is given combined, the antagonizing effect is even better.