抄録
Bioavailability of calcium carbonate, DL- or L-calcium lactates and powdered oyster shell as dietary calcium sources was investigated .Vitamin D-deficient rats were fed ad libitum a diet with normal calcium contents (0.44%) adjusted with one of the above four kinds of calcium compounds under vitamin D-deficient or -replete conditions for a week. During and after feeding, the concentrations of calcium, phosphorus and parathyroid hormone in plasma were measured. In addition, plasma alkaline phosphatase activity and femoral mineral contents were also measured. Among the compounds, the bioavailability of L-calcium lactate and powdered oyster shell appeared to be slightly better than the other two compounds in the increase of body weights, plasma calcium and phosphorus levels and femoral mineral contents, and the decrease of plasma parathyroid hormone level and alkaline phosphatase activity in vitamin D-replete condition. However, there was no significant difference among the compounds in vitamin D-deficient condition.
