Phospholipase A(2) activity, heat shock protein, and superoxide dismutase in rat remnant kidney.
Male Sprague-Dawley rats (150-200 g) were randomly assigned to sham operation (n=6) or 5/6 nephrectomy (n=12) procedures. Two weeks after the completion of the 5/6 nephrectomy, these animals were again randomly assigned to two groups: non-treatment or treatment with vitamin E supplementation at 200 IU/kg chow. Two weeks later, all animals were sacrificed and the kidneys harvested. The secretory phospholipase A(2) (PLA(2)) activity was elevated (150%) in the untreated remnant kidney but returned to sham values in the vitamin E-treated kidneys. The cytoprotective heat shock protein (HSP70) and the intracellular antioxidant superoxide dismutase (MnSOD, Cu/ZnSOD) were similar in sham, remnant, and vitamin E-treated remnant kidneys. We conclude that the sudden reduction of renal mass secondary to the 5/6 nephrectomy procedure stimulates PLA(2) activity but not HSP70, MnSOD, or Cu/ZnSOD. This increased activity of PLA(2) in the remnant kidney returned to sham values after vitamin E treatment. The intrinsic cellular antioxidant enzymes, MnSOD, Cu/ZnSOD, as well as the cytoprotective heat shock protein HSP70, showed no significant changes in either vitamin E-treated or untreated kidneys compared with sham. These data are suggestive that the elevation of PLA(2) is a specific and localized response to the sudden reduction of renal mass.
Dorsam
G
G
Department of Pediatrics, Virginia Commonwealth University, Richmond, VA 23298, USA.
Krieg
R J
RJ
Chan
W
W
Ereso
G
G
Lin
K C
KC
Chan
J C
JC
D000818:Animals; D004790:Enzyme Induction; D018840:HSP70 Heat-Shock Proteins / Q000187:drug effects / Q000378:metabolism*; D007668:Kidney / Q000187:drug effects / Q000378:metabolism*; D008297:Male; D009392:Nephrectomy / Q000379:methods; D010741:Phospholipases A / Q000187:drug effects / Q000378:metabolism*; D051381:Rats; D017207:Rats, Sprague-Dawley; D013482:Superoxide Dismutase / Q000187:drug effects / Q000378:metabolism*; D014810:Vitamin E / Q000494:pharmacology
D018840:HSP70 Heat-Shock Proteins; D014810:Vitamin E; D013482:Superoxide Dismutase; D010741:Phospholipases A