Immunohistochemical localization of glutathione-S-transferase and glutathione peroxidase in adult Syrian hamster tissues and during kidney development.

Tissues from adult Syrian hamsters were studied with immunoperoxidase techniques using polyclonal antibodies to glutathione-S-transferase (rat liver and human placental enzymes) and human erythrocyte glutathione peroxidase. Most tissues immunostained similarly with these antibodies. Most notable was the cytoplasmic staining of mesenchyme tissues, especially smooth muscle, by all three antibodies. Epithelial cells stained distinctively, but usually less intensely than mesenchyme. Epithelial cells from all levels of the gastrointestinal tract, respiratory epithelium, transitional epithelium, and epidermis all showed strong staining with these antibodies. Other epithelial cell types were usually positive but showed less dramatic staining. Most epithelial tissues showed both nuclear and cytoplasmic staining; some also showed cell-surface (eg, cilia) staining. The role of these enzymes in cell differentiation of a stable organ was studied by immunostaining the kidney during its development. Early stroma (13- and 15-day fetuses) of the kidney (metanephric mesenchyme) showed strong cell-surface staining for glutathione transferases and moderate staining for glutathione peroxidase; renal tubules (which are epithelial cells) at this stage were negative for these markers. As renal tubules differentiated, first cytoplasm and then nuclei stained moderately, suggesting that glutathione-S-transferases and glutathione peroxidase are markers of both mesenchymal cells, including embryonic mesenchyme, and terminal differentiation of at least some epithelial cells.