Effect of free radical scavenger (tempol) on intrarenal oxygenation in hypertensive rats as evaluated by BOLD MRI.
OBJECTIVE
To demonstrate a differential response following administration of a free radical scavenger, tempol, in kidneys of hypertensive compared to normotensive rats.


METHODS
Data were obtained in spontaneously hypertensive rats (SHR, N = 5). Wistar-Kyoto rats (WKY, N = 6) were used as normotensive controls.


RESULTS
Consistent with prior reports, SHRs show a significant response to tempol (R(2)*decreased from 40.56 +/- 0.66 second(-1) to 28.58 +/- 0.6 second(-1) in medulla, P < 0.05), while WKY rats exhibit a minimal change (R(2)* measuring 22.36 +/- 4.38 second(-1) pre-tempol and 21.57 +/- 4.78 second(-1) post-tempol, in medulla). The post-tempol R(2)* in SHR was found to be comparable to pre-tempol values in WKY rats, suggesting an improved medullary oxygenation in SHRs.


CONCLUSIONS
Based on both baseline R(2)* values and the differential effect of the free radical scavenger on renal medullary oxygenation, BOLD MRI can distinguish hypertensive from normal kidney in rats.
Li
Lu-Ping
LP
Department of Radiology, Evanston Northwestern Healthcare, Evanston, Illinois, USA. lli@enh.org
Li
Belinda S Y
BS
Storey
Pippa
P
Fogelson
Laura
L
Li
Wei
W
Prasad
Pottumarthi
P
D000818:Animals; D003497:Cyclic N-Oxides / Q000494:pharmacology*; D016166:Free Radical Scavengers / Q000494:pharmacology*; D006973:Hypertension / Q000378:metabolism*; D007679:Kidney Medulla / Q000187:drug effects* / Q000378:metabolism*; D008279:Magnetic Resonance Imaging / Q000379:methods; D010100:Oxygen / Q000378:metabolism*; D051381:Rats; D011918:Rats, Inbred SHR; D011921:Rats, Inbred WKY; D013113:Spin Labels; D013997:Time Factors
D003497:Cyclic N-Oxides; D016166:Free Radical Scavengers; D013113:Spin Labels; D010100:Oxygen; C001803:tempol
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