Hepatic bile salt transport. A review of subcellular binding sites.

Bile-salt transport is an example of the remarkable ability of the liver to remove anions rapidly and efficiently from blood and excrete them into bile. It appears that uptake of bile salts involves receptor proteins in the hepatocyte membrane whereas transport across the cell is by diffusion in free solution. Excretion into bile may also require receptor proteins. It is worth emphasizing that many of the studies described in this review were performed in rats. Unlike humans the rat does not possess a gall bladder and it seems likely, therefore, that in this animal hepatic bile-salt uptake will occur at a relatively constant rate throughout the day. In the human, however, little uptake will occur during periods of fasting, since the bile-salt pool is retained in the gall bladder.