Abstract:
:Phosphorus NMR can measure myocardial tissue pH from the chemical shift of inorganic phosphate (Pi) in isolated buffer-perfused hearts, but in vivo the Pi peak originating from the myocardium is obscured by the resonance of 2,3-diphosphoglycerate (DPG) in the blood, making pH difficult to determine. Taking advantage of the fact that most of the interfering DPG is within the cardiac chambers and is rapidly flowing out of the sensitive volume of our coil, we developed a pulse sequence which would separate myocardial Pi signal from interfering DPG. We tested this method on a flow phantom and in living rat heart, using exogenous glycerol phosphate as a blood-pool marker. The results indicated that signal from moving and nonmoving substances could be separated, and derived values for myocardial pH and PCr/Pi ratio were consistent with previous estimates. This method should be useful for studying myocardial acid-base physiology with NMR.
journal_name
Magn Reson Medjournal_title
Magnetic resonance in medicineauthors
Zahler R,Majumdar S,Frederick B,Laughlin M,Barrett E,Gore JCdoi
10.1002/mrm.1910170209subject
Has Abstractpub_date
1991-02-01 00:00:00pages
368-78issue
2eissn
0740-3194issn
1522-2594journal_volume
17pub_type
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journal_title:Magnetic resonance in medicine
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更新日期:2010-08-01 00:00:00
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pub_type: 临床试验,杂志文章,随机对照试验
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