Comparison of gene expression in cell culture to that in the intact animal: relevance to drugs and environmental toxicants. Focus on "development of a transactivator in hepatoma cells that allows expression of phase I, phase II, and chemical defense genes".

TO STUDY THE EFFECTS OF DRUGS and other environmental toxicants on the liver, many believe that the use of hepatocytederived cultures offers advantages over studies in the liver of intact animals. Cell cultures can be manipulated more easily, and they are far less expensive to maintain than a laboratory animal or transgenic mouse colony. Indeed, this is the theme of this section (Cell Physiology) of the American Journal of Physiology. Do signaling pathways and metabolism in hepatocytes in culture, however, reflect those in the intact animal? Can drugs and other environmental toxicants elicit the same subcellular response in isolated or cultured hepatocytes, or in hepatoma established cell lines, as in the liver of the intact animal?