Glutathione S-transferase activities have been identified in the small intestine of the rat. Thrree activities obtained with p-nitrobenzyl chloride (aralkyl), 1,2-epoxy-3-(p-nitrophenoxy)propane (epoxide), and ethacrynic acid (alkene) as substrates were present in significant amounts. Gel filtration indicated an elution volume for the intestinal transferase activities that was similar to those activities in the liver and kidney. The induction of the intestinal transferases by polycyclic aromatic hydrocarbons and phenobarbital is similar to those effects observed previously for the hepatic and renal enzymes. The highest concentration of transferase activities occurs in the proximal small intestine; these activities are reduced upon fasting. Parallel observations have been reported for aryl hydrocarbon hydroxylases. Because only low or negligible levels of epoxide hydrases have been reported in the small intestine, the glutathione S-transferases may be the primary epoxide-detoxifying system in that organ.
↵1 Supported through funds provided by the Bureau of Medicine and Surgery, Navy Department, for 5-48-494C, and by the Veterans Administration Medical Research. The opinions and assertions contained herein are those of the authors and are not to be construed as official or as reflecting the views of the Navy Department or the naval service at large.
↵2 To whom requests for reprints should be addressed.
- Received July 13, 1976.
- Accepted December 2, 1976.
- ©1977 American Association for Cancer Research.