Localization of Heat Shock Protein 72 in Potassium-deprivated Rat Kidney / 대한해부학회지

ABSTRACT

Heat shock protein 72 (HSP72) appears to play an important role in cell survival in the hypertonic conditions of the renal medulla. The purpose of this study was to examine the effect of potassium deprivation on renal HSP72 expression. Male Sprague-Dawley rats were fed potassium deficient diet for 2 weeks. Kidney tissues were preserved by in vivo perfusion with paraformaldehyde-lysine-periodate (PLP) and processed for Western blot analysis and immunocytochemistry. Serum potassium concentration and urine osmolality decreased in potassium deprivated animals. In control kidneys, HSP72 immunostaining was observed mainly in the inner medulla in almost all cells including the inner medullary collecting duct and papillary surface epithelial cells. In potassium deprivated kidneys, HSP72 expression decreased dramatically in the inner medulla. However, strong HSP72 immunostaining remained in some inner medullary collecting duct and papillary surface epithelial cell. These results demonstrated that potassium deprivation induced down regulation of HSP72 in the renal medulla, at least in part, through cell-specific manner.