EFFECT OF ISCHEMIA ON LOCALIZATION OF HEAT-SHOCK-PROTEIN-25 IN KIDNEY

The effects of renal ischemia on the intracellular distribution of the low-molecular weight heat shock protein (HSP)25 were examined using i mmunofluorescence microscopy. In all kidney zones, ischemia decreased HSP25 in the supernatant of the tissue homogenates and increased it in the pellet fraction (containing mainly nuclei and cytoskeletal compon ents). This was associated with disappearance of HSP25 staining from t he brush border of proximal convoluted tubule (PCT) cells. Because no nuclear staining of cortical tubule cells was apparent either in contr ol or ischemic kidneys, ischemia seems to cause a closer association o f HSP25 with cytoskeletal components. HSP25 probably participates in t he postischemic restructuring of the cytoskeleton of PCT cells.