NON-INDUCIBILITY OF THE GLUTATHIONE TRANSFERASES OF THE EARTHWORM EISENIA-ANDREI

1. Earthworms were exposed to solutions of potential biotransformation enzyme inducers, i.e. trans-stilbene oxide (0.1 mM), 3-methylcholanth rene (50 mu M) or 1,4-bis[2-(3,5-dichloropyridoxyl)]benzene (30 mu M) for 1 hr each day in three successive days. 2. Glutathione transferase (GST) was determined in cytosolic extracts of the worms the day after the last treatment, with chloro-2,4-dinitrobenzene, 1,2-dichloro-4-ni trobenzene and ethacrynic acid as electrophilic substrates. Activity t oward 1,2-epoxy-3-[p-nitro-fenoxy]propane was not detected. 3. With al l three substrates, the specific activity in the cytosol was similar i n treated animals and controls. 4. Ion exchange chromatography was per formed on a NeoBar AQ(TM) column (The ''Low Pressure High Performance' ' technique), and GST eluted in four distinct peaks. 5. The elution pr ofiles of GST activity were almost identical for exposed earthworms an d controls. 6. The results suggest that earthworms may not have induci ble GST, perhaps because they are detritus eaters, and do not need to detoxicate poisonous secondary plant metabolites.