Abstract
High magnesium intakes are known to inhibit the development of nephrocalcinosis in female rats but there was no information on the dose-response relationship and the underlying mechanism In an attempt to collect the lacking information, female rats were fed diets containing 0 02-0 24% magnesium as the only variable Increasing dietary magnesium concentrations were found to reduce nephrocalcinosis in a dose-dependent fashion The lowest dietary magnesium level produced a kidney calcium concentration of 10 6% in the dry matter whereas the highest magnesium intake reduced kidney calcium to 0 2% Increasing dietary magnesium concentrations produced increasing urinary magnesium concentrations in combination with decreasing phosphorus concentrations It is suggested that the magnesium-induced inhibition of nephrocalcinosis is caused by a decrease in urinary phosphorus and increase in urinary magnesium