Immunohistochemical localization of glutathione S-transferase pi in rainbow trout olfactory receptor neurons.

In the fish olfactory system, glutathione S-transferases (GST) which detoxify electrophilic substances and participate in reactions of lipophilic compounds, may be active in the biotransformation of odorants and xenobiotics. In this study GST activity in the rainbow trout olfactory mucosa was high (477.6 +/- 218 nmol/min per mg protein). The GST pi class was demonstrated by Western immunoblot analysis and localized by immunofluorescence to the dendritic and perinuclear regions of olfactory receptor neurons; areas previously shown to contain elevated glutathione. The presence of GST and glutathione in fish olfactory receptor neurons suggests that these cells utilize the glutathione pathway.