Superoxide dismutase and oxidative stress in Dahl salt-sensitive and -resistant rats.
The roles of oxidative stress and renal superoxide dismutase (SOD) levels and their association with renal damage were studied in Dahl salt-sensitive (S) and salt-resistant (R)/Rapp strain rats during changes in Na intake. After 3 wk of a high (8%)-Na diet in S rats, renal medullary Cu/Zn SOD was 56% lower and Mn SOD was 81% lower than in R high Na-fed rats. After 1, 2, and 3 wk of high Na, urinary excretion of F(2)-isoprostanes, an index of oxidative stress, was significantly greater in S rats compared with R rats. Plasma F(2)-isoprostane concentration increased in the 2-wk S high Na-fed group. After 3 wk, renal cortical and medullary superoxide production was significantly increased in Dahl S rats on high Na intake, and urinary protein excretion, an index of renal damage, was 273 +/- 32 mg/d in S high Na-fed rats and 35 +/- 4 mg/d in R high Na-fed rats (P < 0.05). In conclusion, salt-sensitive hypertension in the S rat is accompanied by marked decreases in renal medullary SOD and greater renal oxidative stress and renal damage than in R rats.
Department of Physiology and Biophysics, University of Mississippi Medical Center, Jackson, Mississippi 39216, USA.
Shumei
S
Meng
L Jackson
LJ
Roberts
Garrick W
GW
Cason
Travis S
TS
Curry
R Davis
RD
Manning
D000818:Animals; D000975:Antioxidants / Q000378:metabolism; D004039:Diet, Sodium-Restricted; D028441:F2-Isoprostanes / Q000097:blood / Q000652:urine; D006977:Hypertension, Renal / Q000378:metabolism; D007672:Kidney Cortex / Q000201:enzymology*; D007679:Kidney Medulla / Q000201:enzymology*; D008297:Male; D018384:Oxidative Stress / Q000502:physiology*; D011507:Proteinuria / Q000378:metabolism; D051381:Rats; D020303:Rats, Inbred Dahl; D017382:Reactive Oxygen Species / Q000378:metabolism; D012982:Sodium, Dietary / Q000494:pharmacology; D013482:Superoxide Dismutase / Q000378:metabolism*
D000975:Antioxidants; D028441:F2-Isoprostanes; D017382:Reactive Oxygen Species; D012982:Sodium, Dietary; D013482:Superoxide Dismutase