부산대학교 도서관

The comparative metabolism of Sr/sup 85/ and Ba/sup 140/ was studied in the ends and shaft of the femur, in the molar and incisor teeth, and in the serum, liver, lungs, muscle, and submaxillary giand of rats aged 6 to 8 weeks and 15 months by using double-tracer techniques. In bone the uptake of both Sr/sup 85/ and Ba/sup 140/ decreases with age, and more Ba/sup 140/ than Sr/sup 85/ is retained. It is suggested that this may be due to deposition of Ba/sup 140/ by surface adsorption as well as by exchange. Both Sr/sup 85/ and Ba/sup 140/ are taken up by the incisor teeth of young and old rats, the uptake in the old animal being about twice that of the young rat. In molar teeth the uptakes of both Sr/ sup 85/ and Ba/sup 140/ are similar in old and young animals, but in the old animal both are rapidly removed from these teeth, in contrast with the young animal where retention is prolonged. After intravenous injection the concentrations of Sr/sup 85/ and Ba/sup 140/ in the soft tissues closely follow those in the blood, and except in the submaxillary gland the Sr/sup 85/: Ba/sup 140/ ratio is always greater than 1. The submaxillary gland concentrates both Sr/ sup 85/ and Ba/sup 140/ from the serum, but the concentration of Ba/sup 140/ is always greater than that of Sr/sup 85/. The uptake of both Sr/sup 85/ and Ba/sup 140/ in soft tissues is generally in proportion to the calcium content of the tissues. (auth)