23Na-NMR detects hypoxic injury in intact kidney: increases in sodium inhibited by DMSO and DMTU.
Hypoxic injury in the isolated perfused rat kidney (IPRK) was monitored using 23Na-NMR in the presence or absence of 1.5 and 15 mM dimethylthiourea (DMTU) or 15 mM dimethylsulphoxide (DMSO) before and after inducing hypoxia. Hypoxia induced a prompt exponential increase in total renal 23Na+, renal vascular resistance, and sodium excretion and decreased inulin clearance and adenine nucleotides and reduced glutathione concentrations. Lipid peroxide metabolites were unaltered. The increase in 23Na+ was significantly reduced (P < 0.001) by both DMTU and DMSO although hypoxic perturbations of function and biochemical parameters were not. Posthypoxic increases in renal 23Na+ include approximately 10% from the intratubular compartment, but principally reflect the intracellular and interstitial compartments. The results demonstrate that 23Na-NMR is a sensitive indicator of hypoxic renal injury in intact kidney and suggest that DMTU and DMSO protect against hypoxic injury by a mechanism independent of free radical-binding.
Cross
M
M
Department of Medicine and Biochemistry, University of Queensland, Australia.
Endre
Z H
ZH
Stewart-Richardson
P
P
Cowin
G J
GJ
Westhuyzen
J
J
Duggleby
R G
RG
Fleming
S J
SJ
D000818:Animals; D004121:Dimethyl Sulfoxide / Q000627:therapeutic use*; D000860:Hypoxia / Q000150:complications*; D007674:Kidney Diseases / Q000209:etiology* / Q000378:metabolism; D009682:Magnetic Resonance Spectroscopy; D008297:Male; D051381:Rats; D017208:Rats, Wistar; D012964:Sodium / Q000378:metabolism*; D013890:Thiourea / Q000031:analogs & derivatives* / Q000627:therapeutic use
C038983:1,3-dimethylthiourea; D012964:Sodium; D013890:Thiourea; D004121:Dimethyl Sulfoxide