Item Type: | Article |
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Title: | Blood oxygen level-dependent MRI of tissue oxygenation. Relation to endothelium-dependent and endothelium-independent blood flow changes |
Creators Name: | Utz, W., Jordan, J., Niendorf, T., Stoffels, M., Luft, F.C., Dietz, R. and Friedrich, M.G. |
Abstract: | OBJECTIVES: The contribution of endothelial function to tissue oxygenation is not well understood. Muscle blood oxygen level-dependent MRI (BOLD MRI) provides data largely dependent on hemoglobin (Hb) oxygenation. We used BOLD MRI to assess endothelium-dependent signal intensity (SI) changes. METHODS AND RESULTS: We investigated mean BOLD SI changes in the forearm musculature using a gradient-echo technique at 1.5 T in 9 healthy subjects who underwent a protocol of repeated acetylcholine infusions at 2 different doses (16 and 64 microg/min) and N(G)-monomethyl-L-arginine (L-NMMA; 5 mg/min) into the brachial artery. Sodium nitroprusside was used as a control substance. For additional correlation with standard methods, the same protocol was repeated, and forearm blood flow was measured by strain gauge plethysmography. We obtained a significant increase in BOLD SI during acetylcholine infusion (64 microg/min) and a significant decrease for L-NMMA infusion (P<0.005 for both). BOLD SI showed a different kinetic signal than did blood flow, particularly after intermittent ischemia and at high flow rates. CONCLUSIONS: In standard endothelial function tests, BOLD MRI detects a dissociation of tissue Hb oxygenation from blood flow. BOLD MRI may be a useful adjunct in assessing endothelial function. |
Keywords: | Magnetic Resonance Imaging, Endothelial Function, BOLD, Plethysmography |
Source: | Arteriosclerosis Thrombosis and Vascular Biology |
ISSN: | 1079-5642 |
Publisher: | American Heart Association |
Volume: | 25 |
Number: | 7 |
Page Range: | 1408-1413 |
Date: | July 2005 |
Official Publication: | https://doi.org/10.1161/01.ATV.0000170131.13683.d7 |
PubMed: | View item in PubMed |
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