From blood to bile: recent advances in hepatobiliary transport.

Transport of endogenous and exogenous substances from blood to bile is an essential function of the liver. In the last decade a still growing number of specific transport proteins present at the sinusoidal and canalicular membrane domains of hepatocytes and cholangiocytes have been cloned and functionally characterized. Studies assessing the molecular expression and function of these hepatobiliary transport proteins under different experimental conditions has helped to define the adaptive responses of hepatocytes to certain physiological states and to cholestatic liver injury and to a better understanding of the physiology of bile formation and of the pathophysiology of certain cholestatic diseases. Particularly relevant is the elucidation of the molecular bases of several forms of inherited cholestatic liver disease, which may help to the development of better diagnostic tools or to the design of new therapeutic strategies. In the present review we summarize recent experimental and clinical data involving hepatobiliary transport mechanisms.