Topographic analysis of the microdistribution of 241Am in the rat femur as influenced by DTPA treatment.
Topographic analysis of the microdistribution of 241Am in the rat femur as influenced by DTPA treatment.
复制标题
受 DTPA 处理影响的大鼠股骨中 241Am 微分布的形貌分析。
作者：
E. Polig
The influence of growth and Na/sub 3/Ca-DTPA treatment on the microscopic distribution of Am(III) in the distal femora of 8-week-old female rats were examined by means of solid-state nuclear-track detectors and an electronic scanning technique. The iv dose of (/sup 241/Am)citrate was 30 ..mu..Ci/kg; Ca-DTPA was administered ip once weekly in a dose of 30 ..mu..mole/kg, and the first dose was injected 1.5 hr after the /sup 241/Am. The animals were sacrificed 7, 14, 28, and 56 days after the /sup 241/Am injection. The distribution of /sup 241/Am was presented as computer-generated scan plots giving quantitative information about radiation dose rates. The redeposition of /sup 241/Am in newly formed bone tissue between the zone of heavy initial uptake and the epiphyseal cartilage plate was absent in the case of DTPA treatment. There was a diminution of activity by DTPA in the metaphyseal band to 40 percent of the control values on the 7th day and to 26 percent on the 56th day. While DTPA does not significantly affect removal of the epiphyseal deposit of /sup 241/Am, there is a continuing effectiveness in the metaphysis and diaphysis, yielding a reduction to 70 percent of the control radioactivity at the 7th day,more » and 28 percent at the 56th day. Bone remodeling tended to increase the nonuniformity of the dose-rate distribution, which, for example, led to an enhancement of the maximum dose rates in the metaphyseal band. This increase of the nonuniformity of the dose-rate distribution is even enhanced by DTPA treatment. The information contained in the dose-rate scans was reduced to probability density curves and compared for the effects of aging and DTPA.« less
