$sup 85$Sr retention in Japanese after single administrations

The retention of /sup 85/Sr administered intravenously or orally to 14 Japanese was studied for a period of less than one month. The whole-body retention curve, as determined from excreta, could be fitted well by a sum of two component exponential functions when the amount of /sup 85/Sr exogenously excreted into the feces was excluded. However, the sizes and the rate constants of the respective components varied with individuals. The absorption coefficient of /sup 85/Sr was calculated for four subjects and found to be about 50% for normal cases and 30% for subjects with osteoporosis. Cumulative urinary excretion of /sup 85/Sr was not less than cumulative fecal excretion for absorbed /sup 85/Sr. The fractions (f/sub u/) of the element excreted in 24 hr urine over that in 24 hr total excreta of both stable Sr and Ca, which included exogenous origins, were higher for the subjects in this study than those for the normal male adults. The fraction varied greatly day to day when the amount of stable Sr exogenously excreted into the feces was included in this calculation. A higher content of stable Sr in the excreta of the subjects in this study was generally observed in comparison withmore » that of the normal male adults, but the amount of Ca in excreta of the subjects in this study was comparable to that of the normal male adults. (auth)« less