The Effects of Diet Calcium, Protein and Acidity on Calcium Retention in the Rat, Particularly as Related to the Inner and Outer Surfaces of Tubular Bone: A Possible Model for the Treatment or Prevention of Osteoporosis

摘要

The effects of graded levels of diet calcium, protein and acidity on radiographic and gravimetric measurements, and on mineral composition of femurs were studied in Long Evans, young and old, female rats. With increased diet calcium, femur potassium percent in ash is decreased in both young and old rats. Otherwise, bone (as a tissue) is chemically unaffected by diet treatment. Increasing diet protein results in increased bone turnover at both bone surfaces, as well as increased cortical area and bone density in young rats. The effects of graded levels of diet calcium, protein and acidity on soft tissue calcification were also studied in female rats fed diets with varying magnesium levels which met National Research Council Requirements but which induced elevated kidney calcium levels as reported by some reseachers. Low magnesium diets in the young growing rat induced nephrocalcinosis which was shown by histopathologic examination to be an intracellular-initated dystrophic calcification.