Localisation of alpha, mu and pi class glutathione S-transferases in kidney: comparison with CuZn superoxide dismutase

We describe studies in whole kidney, cortical and medullary homogenates and, glomerular cells in culture to determine the relative levels of expression of alpha (Ya, Yc, Yk), mu (Yb1/Yb2), pi (Yf) glutathione S-transferases (GST) and CuZn superoxide dismutase (CuZn SOD) in different regions of the nephron. Immunoblotting and immunohistochemistry were used to demonstrate relatively weak expression of alpha, mu GST and, CuZn SOD in the glomerulus compared to that in particularly distal tubules. Whilst expression of Ya was found within glomerular cells, Yc, Yk and Yf were not detected. Immunofluorescence showed that Ya and Yb1/Yb2 but not Yf were expressed in cultured epithelial and mesangial cells studied between passages 1 and 3. While Ya was distributed in cytosol, Yb1/Yb2 was primarily located in nuclei.