Absorption of Cu64, Zn65, Mo99, and Fe59 from Ligated Segments of the Rat Gastrointestinal Tract

Abstract
Portions of rat intestinal tract were ligated to provide the following isolated, in vivo, segments: stomach: duodenum, mid-section, or ileum. In successive studies, Cu64, Zn65, Fe59, or Mo99 was injected into one of the ligated segments. After a predetermined period of time, the rats were killed and tissue samples were taken for isotope analysis. On the basis of these tissue counts, the following relative rates of absorption were indicated. For Cu64, absorption was greatest from the stomach and declined as the isotope was placed further away from the pylorus. Zn65 and Fe59 were taken up most rapidly from the duodenum, somewhat more slowly from the ileum and the mid-section, and with the least absorption occurring from the stomach. Mo99 was absorbed readily from the stomach and all 3 intestinal segments. Absorption from the 3 intestinal segments was at similar rates and all three yielded significantly higher rates than the stomach.