Purpose: To develop a free cell suspension of rat hepatocytes in order to study enzyme release into the entracellular fluid. Methods: The livers of Wistar rats were perfused in vivo through the portal vein with calcium free Lock solution containing EDTA. The liver was removed, placed in Krebs-Ringer solution, homogenized, and the hepatocytes separated by centrifugation. The cells were incubated for periods up to 180 minutes to assay protein concentration, asparagine aminotransferaseactivity, alanine aminotransferase activity, and aminoacyl-tRNA synthetase activity in the extracellular solution.Results: Asparagine and alanine aminotransferase activity in the solution increased with time of incubation. Aminoacyl-tRNA anythetase acitivity decreased with time and degradation products of RNA did not change with time. Conclusion: This process produced intact functioning hepatocytes in solution as measured by release of aminotransferases without release of aminoacyl-tRNA synthetase. This experimental model appears useful for the study of hepatocyte enzyme synthesis and release.

Keywords: free cells, rat liver, Aminotransferases, aminoacyl-tRNA synthetase