Immunocytochemical Localization of Glutathione Peroxidase in Uremic Rat Kidney

Plasma Glutathione Peroxidase Deficiency Caused by Renal Dysfunction

“…Semiquantitation of EGPx was carried out by immu noblot analysis of the plasma using chicken anti-EGPx antibody. As shown in figure 2, an immunostained band of 22.5 kD was clearly observed in the plasma from healthy controls (lanes 1-3), while the band was faint (lanes [4][5][6][7][8] or undetectable (lane 9) in the plasma of non dialyzed patients. The sample applied in lane 9 was from a nondialyzed patient whose plasma GPx activity was lowest (0.021 U/ml) and serum creatinine level was high est (7.1 mg/dl).…”

“…Both enzymes contain a selenium (Se) atom at the active site in the form of selenocysteine [1], EGPx is dis tinct from cellular GPx in substrate specificity [2], gene structure, and gene localization on a different chromo some [$]. EGPx accounts for almost all the peroxidase activity in the plasma [4], and is believed to play a key role in the plasma antioxidant defense system [5], It has been found that GPx activity is low in the serum of partially nephrectomized uremic rats [6] and in patients on hemo dialysis, although the mechanism has not been elucidated [7,8]. In a previous study, we examined the expression of EGPx in 13 rat tissues by immunoblot and Northern blot analyses [9], and demonstrated that rat kidney is the main source of EGPx.…”