Preparation, morphology and drug metabolism of isolated hepatocyte and liver organ cultures from the human fetus

Isolated hepatocytes of human fetuses (week 9–20 of gestation) were prepared by digestion of liver slices with Dispase l and repeated centrifugations. These cells metabolized drugs by first order kinetics for at least 4 h and retained their drug metabolizing enzyme activities for more than 24 h. Using cultures of human fetal liver slices (week 5–20 of gestation) first order kinetics of drug metabolism could be measured for up to 3 days. These findings correlate well with concomitant morphological studies. Electron microscopy revealed that the liver cells of human fetuses (week 9–20 of gestation) contained numerous cavities of the rough endoplasmic reticulum (ER) and only single membranes of the smooth ER. The isolated liver cells maintained their morphological integrity for up to 24 h in culture. Sections derived from liver slices cultured for up to 3 days did not show any significant morphological alterations, except for some swellings of mitochondria, vacuolisations and fat inclusions that occurred in the sinus endothelia and blood cells. A gradual disintegration began on day 4, and after 7 days intact cells could no longer be demonstrated. The metabolism of the benzodiazepine drugs prazepam, diazepam and medazepam as well as diphenylhydantoin, hexobarbital and halothane were measured in these systems. Both the isolated hepatocyte and liver organ cultures should be useful to study whether a relationship exists between the emryotoxicity of certain drugs and their metabolism in the human fetus.