Tissue disposition of 26aluminum in rats measured by accelerator mass spectrometry.

A trace quantity of 26aluminum (26Al) was administered intravenously to 1 normal and 1 uremic rat. After a 3-week period, the animals were sacrificed and samples of bone, muscle, kidney, liver, heart, and brain were analyzed for their 26Al content. In the normal and uremic rats, most of the tissue 26Al was found in bone amounting to 0.9% and 2.0%, respectively, of administered dose/g dry weight of tissue. Much smaller amounts of isotope were found in the other tissues in both animals. In the normal rat, the descending order of 26Al content in other tissues was: kidney, 0.2% > liver, 0.06% > heart, 0.03%, > brain and muscle, 0.02%. In the uremic rat, the same order of tissue 26Al content was found with kidney, 0.37% > liver, 0.06% > heart, 0.02% > brain and muscle, 0.01% per g dry weight of tissue. When expressed per g wet weight of tissue in the 2 animals, a similar order of tissue 26Al content was found. In comparing the amount of 26Al in the bone of the 2 rats, the uremic animal was found to have more than twice that found in the bone of the normal rat when expressed either per g dry or wet weight of bone. However, 26Al content of other tissues was similar in the 2 animals. This suggests that uremic bone may have a greater affinity for aluminum than normal bone, but kidney, liver, brain, heart, and muscle appear to behave similarly in uremic and normal rats in regard to incorporation of a single trace dose of isotope in the 3-week time frame of the present study.