Evaluation of intrarenal oxygenation in mice by BOLD MRI on a 3.0T human whole-body scanner.
OBJECTIVE
To extend observations on intra-renal oxygenation with blood oxygen level-dependent (BOLD) MRI in human and rats to mouse kidneys imaged with a human whole-body scanner.


METHODS
Renal BOLD MRI studies were performed on a 3.0T scanner using a multiple gradient-echo (mGRE) sequence with a custom-designed 2.0-cm surface coil to acquire six T(2)*-weighted images in mice (N = 8) at an in-plane resolution of 156 x 156 mum(2). BOLD MRI data were obtained before and after administration of furosemide (10 mg/kg intravenously [i.v.]).


RESULTS
The mean weight of eight mice was 24.6 +/- 1.0 g. The baseline renal R(2)* (mean +/- standard error [SE]) was 28.6 +/- 2.1 seconds(-1) in the renal cortex (CO), 35.4 +/- 2.2 in the outer medulla (OM), and 21.2 +/- 2.1 seconds(-1) in the inner medulla (IM). The BOLD response to furosemide (DeltaR(2)*) was 4.1 +/- 1.4 in the CO, 10.1 +/- 2.1 seconds(-1) in the OM, and 3.4 +/- 0.8 seconds(-1) in the IM in mice.


CONCLUSIONS
Intrarenal BOLD MR images with sufficiently high resolution can be obtained on a human whole-body scanner when combined with a small receiver coil to allow studies in mice. Both baseline R(2)* and DeltaR(2)* values following administration of furosemide were consistent with previous experience in humans and rats.
Li
Lu-Ping
LP
Center of Advanced Imaging, Department of Radiology, Evanston Northwestern Healthcare, Evanston, Illinois 60201, USA.
Ji
Lin
L
Lindsay
Scott
S
Prasad
Pottumarthi V
PV
D000818:Animals; D004232:Diuretics / Q000008:administration & dosage; D005665:Furosemide / Q000008:administration & dosage; D007668:Kidney / Q000033:anatomy & histology / Q000187:drug effects / Q000378:metabolism*; D007672:Kidney Cortex / Q000033:anatomy & histology / Q000187:drug effects / Q000378:metabolism; D007679:Kidney Medulla / Q000033:anatomy & histology / Q000187:drug effects / Q000378:metabolism; D008279:Magnetic Resonance Imaging / Q000295:instrumentation* / Q000379:methods*; D008280:Magnetics; D008297:Male; D051379:Mice; D008807:Mice, Inbred BALB C; D010100:Oxygen / Q000097:blood*; D051598:Whole Body Imaging / Q000379:methods*
D004232:Diuretics; D005665:Furosemide; D010100:Oxygen