The age dependence of bile acid metabolism in rats.

The age dependence of bile acid metabolism in rats was investigated and the following results were obtained. 1) Synthesis rate, pool size and total secretion decreased in old rats (24 month) significantly compared to young rats (6 weeks). 2) The quotient of taurine to glycine conjugates is is significant lower in old rats compared to young rats. 3) The lithogenic index remains unchanged in all age groups. 4) Old rats show a significantly higher Km for cholic acid uptake, whereas the diffusion coefficient is decreased. The possible influence of humoral factors on age dependent regulations of bile metabolism is discussed.