Utilization of a radioiodinated bile salt for kinetic studies and hepatic scintigraphy. Studies in nonhuman mammals.

An 125I- or 131I-labeled bile salt derivative, cholylglycyliodohistamine, has been synthesized and purified. The bile salt derivative is rapidly cleared from the circulation when injected intravenously into rats and rabbits. Ten minutes after injection, approximately 50% of the recovered bile salt derivative was in the jejunum and ileum, and 36% was found in the liver. Sixty minutes after injection, 99% of the recovered radioactivity was found in the luminal gastrointestinal tract. The isotope was cleared from the circulation of rabbits with a t1/2 of approximately 2 min. Hepatic scintigraphy using rabbits demonstrated rapid uptake by the liver and excretion into the intestine. Quantitative analysis of scintigraphy showed an uptake rate of 14%/min and a subsequent excretory rate of 4.6/min.