EFFECT OF DIETARY-FAT LEVEL ON THE CALCIUM CONTENT OF HEART AND KIDNEY IN DBA 2 AND C57BL/6 MICE/

High-fat and low-fat diets were fed for 24 weeks to two strains of mic e differing in susceptibility to the development of dystrophic cardiac calcinosis (DCC). The severity of DCC was assessed by histological ex amination and measurement of heart calcium concentrations. Plasma and renal tissue mineral levels were also measured. On the basis of macros copic examination, feeding the high-fat diet did not influence the sev erity of DCC in the susceptible DBA/2 mice. Heart calcium concentratio ns were reduced in both strains; in DBA/2 mice more than in DCC-resist ant C57BL/6 mice. Cardiac concentrations of magnesium and phosphorus w ere similar in the two strains of mice and unaffected by the amount of dietary fat. Kidney calcium concentrations were higher in the DBA/2 t han in the C57BL/6 mice and the high-fat diet also reduced kidney calc ium concentrations in the DBA/2 mice. The amount of dietary fat, at le ast during growth and maintenance, did not appear to affect the develo pment of DCC in DBA/2 mice.