Biliary excretion of barium was studied in Sprague-Dawley bileduct-cannulated rats injected intravenously with 1.8 μg Ba/rat as133Ba-labeled barium chloride. Approximately 0.5% of the barium dose was excreted into bile within 2 h. The time-course profile of biliary excretion of the radiotracer closely reflected that of plasma concentrations. Biliary barium levels reached their peak in the first 15-min period after administration and rapidly declined thereafter. The plasma-to-bile barium-concentration ratio was approx 1 at 2 h after injection. There was no tendency of barium to concentrate in liver, and the133Ba levels in stomach and small intestine largely exceeded hepatic levels. There is evidence indicating that barium is predominantly excreted with feces following parenteral administration in rats and humans. The results of this study suggest that biliary excretion is of little quantitative importance and that physiological routes other than bile contribute to elimination of barium by the digestive tract.
- barium in rat tissue and plasma
- Biliary excretion of barium
- binding of barium to bile and liver cytosol
- hepatic intracellular distribution of barium
ASJC Scopus subject areas
- Endocrinology, Diabetes and Metabolism
- Biochemistry, Genetics and Molecular Biology(all)