THE EFFECTS OF BACITRACIN ON GLUCAGON-INDUCED METABOLIC CHANGES IN ISOLATED RAT HEPATOCYTES AND ADIPOCYTES

The direct effects of various concentrations of bacitracin on metabolism were observed in either isolated rat hepatocytes or adipocytes. In the hepatocytes from fed rats, 50 nM glucagon-induced glucose production, as well as ketone body production in the presence of 5 mM alanine and 0.25 mM oleate were markedly reduced by higher concentrations of bacitracin (over 0.25 mM) in a dose-dependent manner, and lactate utilization by glucagon also was decreased. In the adipocytes, bacitracin also had a direct suppressive effect on lipolysis induced by 0.25 mM epinephrine, 1.0 mM theophylline and 50 nM glucagon. It is suggested that bacitracin has a direct effect on metabolism in hepatocytes and adipocytes at the concentrations (0.1-5.0 mM) currently being used in incubation studies to prevent peptide hormone degradation, and that careful consideration of the results obtained must be given whenever bacitracin is used in any cell studies.