Freshly isolated mouse hepatocytes were tested with respect to the induction of heat shock (stress) proteins by elevated temperature, sodium arsenite and ethanol treatment. With heat, arsenite and ethanol treatments, the synthesis of a protein with a molecular weight of 68 kD (heat shock protein 68) was predominantly elevated; arsenite and ethanol exerted their effects on heat shock protein synthesis in a dose-dependent manner. Hepatocytes derived from livers of chronically griseofulvin-pretreated mice differed in their response from normal hepatocytes in that ethanol was ineffective in these cells. These results indicate that different modes and pathways of the stress response exist, depending on the nature of the inducing agent but also on pretreatment conditions. In vivo, pathologic alterations of cells and organs (e.g., in the course of chronic diseases) can, therefore, be expected to modulate the stress response.