Influence of magnesium deficiency on concentration of calcium in soft tissue of uremic rats.

The influence of magnesium (Mg) deficiency on the concentration of calcium (Ca) in the aorta, heart, and kidney was evaluated in uremic rats. A total of 32 rats were randomly assigned to two groups: one group made uremic by the 5/6 nephrectomy method, and the other serving as sham-operated controls. Both groups were randomly assigned to two subgroups: one group given a Mg-deficient diet and the other fed a Mg-supplemented diet. After 12 weeks on the regimen, all animals were sacrificed. In Mg-supplemented uremic rats, the concentration of Ca in the aorta was higher than in Mg-supplemented control rats. The concentration of Ca in the aorta was further increased in Mg-deficient uremic rats. The concentrations of Ca in the heart and the kidney were also increased in Mg-deficient uremic rats, as compared with Mg-supplemented uremic rats. The concentration of Mg was decreased in the aorta and increased in the kidney of Mg-deficient rats. There was no significant influence of Mg deficiency on the concentration of phosphate in tissue. Results suggest that Mg deficiency in uremia may increase aortic calcification.