Lack of evidence for vesicle trafficking of fluorescent bile salts in rat hepatocyte couplets

The role of intracellular membrane systems in the delivery of bile salts to the canalicular membrane for secretion was analyzed in rat hepatocyte couplets by confocal scanning fluorescence microscopy (CSFM). CSFM analysis of cellular and canalicular fluorescence from rat hepatocyte couplets indicated the simultaneous occurrence of bile salts across the canalicular membrane and intracellular structures. Furthermore, the dependence of hepatic bile salt secretion on microtubule-dependent vesicle trafficking was indirect and involved the insertion and retrieval of transport proteins.