Abstract: A method of pulsing cultured hepatocytes, such as sandwich-cultured hepatocytes. The method includes providing a culture of hepatocytes, the culture having at least one bile canaliculus; exposing the culture of hepatocytes to a calcium-free buffer, whereby the contents of the at least one bile canaliculus are released; and removing the calcium-free buffer Pulsing cultured hepatocytes can reduce cholestasis arid can provide an in vitro culture of hepatocytes the more closely reflects in vivo hepatocyte characteristics.

Abstract: A method of screening a candidate compound for susceptibility to biliary excretion by a hepatocyte transport protein. The method includes the steps of providing a culture of hepatocytes comprising a transport protein, the culture having at least one bile canaliculus; exposing a candidate compound to the culture; and determining an amount of candidate compound in the at least one bile canaliculus, the amount of candidate compound in the at least one bile canaliculus indicating the susceptibility of the candidate compound to biliary excretion by the transport protein. In some embodiments determining the amount of candidate compound in the bile canaliculus comprises inhibiting expression of the transport protein, measuring the amount of candidate compound in the bile canaliculus and comparing amounts of compound in the canalicules with and without inhibition of the transport protein.