Faculty Collaboration Database

Ischemic conditioning prevents Na,K-ATPase dissociation from the cytoskeletal cellular fraction after repeat renal ischemia in rats. Pediatr Res 2002 Jun;51(6):722-7

Date

05/29/2002

Pubmed ID

12032267

DOI

10.1203/00006450-200206000-00010

Scopus ID

2-s2.0-0036105753 (requires institutional sign-in at Scopus site)   40 Citations

Abstract

Recent studies have suggested that heat shock proteins (HSPs) are involved in the restoration of the cytoskeletal anchorage of Na,K-ATPase after renal ischemia. To determine their role in ischemic conditioning, we investigated whether cytoskeletal Na,K-ATPase was stabilized during repeat ischemia concurrent with 25-kD and 70-kD HSPs induction. Anesthetized rats either underwent single unilateral renal ischemia or were conditioned with bilateral renal ischemia and, after 18 h of reflow, were then subjected to repeat unilateral renal ischemia. Renal cortex was harvested, and effects of single versus repeat ischemia were compared by Triton X-100 extraction, by immunohistochemistry, and by an in vitro assay of Na,K-ATPase association with isolated cytoskeletal fractions. In contrast to single ischemia, repeat ischemia did not result in increased Triton X-100 extractability of Na,K-ATPase. Levels of 25-kD and 70-kD HSPs were significantly induced by ischemic conditioning and redistributed into the cytoskeletal fraction after single and repeat ischemia. Immunohistochemistry also showed significant disruption of Na,K-ATPase within proximal tubules only after a single episode of ischemia, whereas repeat ischemia did not alter the pattern of restored Na,K-ATPase localization in conditioned renal cortex. The preserved association of Na,K-ATPase with the cytoskeletal fraction of conditioned renal cortex was effectively abolished in vitro by addition of antibodies against 25-kD or 70-kD HSP. These results suggest that 25-kD and 70-kD HSPs induced by ischemic conditioning stabilize the cytoskeletal anchorage of Na,K-ATPase during repeat renal ischemia.

Author List

Aufricht C, Bidmon B, Ruffingshofer D, Regele H, Herkner K, Siegel NJ, Kashgarian M, Van Why SK

MESH terms used to index this publication - Major topics in bold

Animals
Cell Fractionation
Cytoskeleton
HSP27 Heat-Shock Proteins
HSP70 Heat-Shock Proteins
Heat-Shock Proteins
Ischemia
Ischemic Preconditioning
Kidney Cortex
Luminescent Measurements
Male
Neoplasm Proteins
Rats
Rats, Sprague-Dawley
Sodium-Potassium-Exchanging ATPase