Phase-modulated rotating-frame spectroscopic localization using an adiabatic plane-rotation pulse and a single surface coil

Hendrich, Kristy; Merkle, Hellmut; Weisdorf, Sally A.; Vine, William; Uğurbil, Kâmil

doi:10.1016/0022-2364(91)90269-y

Cited by 31 publications

(41 citation statements)

References 24 publications

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“…Myocardial PCr/ATP is decreased in patients (22) and in large and small animal models of LVH secondary to pressure and volume overload and postinfarction LV remodeling (11,21,23,36,37,39). Furthermore, abnormalities in oxidative phosphorylation have been described in in vitro studies of failing myocardium (6,32).…”

Section: Discussionmentioning

confidence: 99%

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Oxidative capacity in failing hearts

Gong

Liu

Liang

et al. 2003

American Journal of Physiology-Heart and Circulatory Physiology

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Although high-energy phosphate metabolism is abnormal in failing hearts [congestive heart failure (CHF)], it is unclear whether oxidative capacity is impaired. This study used the mitochondrial uncoupling agent 2,4-dinitrophenol (DNP) to determine whether reserve oxidative capacity exists during the high workload produced by catecholamine infusion in hypertrophied and failing hearts. Left ventricular hypertrophy (LVH) was produced by ascending aortic banding in 21 swine; 9 animals developed CHF. Basal myocardial phosphocreatine (PCr)/ATP measured with 31 P NMR spectroscopy was decreased in both LVH and CHF hearts (corresponding to an increase in free [ADP]), whereas ATP was decreased in hearts with CHF. Infusion of dobutamine and dopamine (each 20 g ⅐ kg Ϫ1 ⅐ min Ϫ1 iv) caused an approximate doubling of myocardial oxygen consumption (MV O2) in all groups and decreased PCr/ATP in the normal and LVH groups. During continuing catecholamine infusion, DNP (2-8 mg/kg iv) caused further increases of MV O2 in normal and LVH hearts with no change in PCr/ATP. In contrast, DNP caused no increase in MV O2 in the failing hearts; the associated decrease of PCr/ATP suggests that DNP decreased the mitochondrial proton gradient, thereby causing ADP to increase to maintain adequate ATP synthesis. heart failure; left ventricular hypertrophy; mitochondria; high-energy phosphates; nuclear magnetic resonance IN NORMAL MYOCARDIUM, it is unclear whether peak O 2 utilization is ultimately limited by maximal oxidative ATP synthetic capacity or by the maximal capacities of the myosin and other ATPases to utilize ATP. In failing myocardium, abnormalities of excitation-contraction coupling as well as downregulation of ␤-adrenergic receptors and the downstream adenylyl cyclase system (25) make it even more difficult to determine whether ATP synthetic capacity limits contractile performance. Hence, the hypothesis that primary "energy starvation" limits function in heart failure (14) remains to be rigorously tested in vivo despite evidence that left ventricular (LV) hypertrophy (LVH) and congestive heart failure (CHF) are associated with abnormalities of myocardial energy metabolism (2,21,22,38,39).Consequently, the present study was performed to determine whether administration of a classical mitochondrial uncoupling agent [2,4-dinitrophenol (DNP)] could further increase myocardial oxygen consumption (MV O 2 ) in hearts with compensated LVH or overt cardiac failure that were already functioning at a high work state produced by catecholamine stimulation. DNP accelerates intramitochondrial metabolism proximal to ATP synthase by decreasing the proton gradient across the inner mitochondrial membrane (17,30). In response to DNP, MV O 2 increases in concert with intermediary metabolism and electron transport activity to maintain the mitochondrial proton gradient that drives ATP synthesis (15,17,30). Although it is unlikely that DNP can define the maximal oxygen utilization capacity in the intact heart (8), it can be used to determine whether there ...

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Section: Discussionmentioning

confidence: 99%

“…Our NMR spectroscopic methods have been described in detail previously (3,10,11,29). Measurements were performed in a 40-cm bore 4.7-T magnet interfaced with a SISCO (Spectroscopy Imaging Systems; Fremont, CA) computer console.…”

mentioning

confidence: 99%

Oxidative capacity in failing hearts

Gong

Liu

Liang

et al. 2003

American Journal of Physiology-Heart and Circulatory Physiology

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“…However, if after this prelabeling [1,[6][7][8][9][10][11][12][13] C 2 ] Glc is infused at the IE of the Glyc C1 resonance, the C1 resonance will remain in isotopic steady state and will act as a pure concentration change monitor, while the C6 resonance signal will increase mostly due to label incorporation, and can in principle be monitored to determine the turnover time. The aim of the present study was therefore to establish the simultaneous measurement of the glycogen C1 and C6 resonances, such that the C1 resonance can be used to determine concentration and the C6 resonance can be used to determine the turnover time.…”

Section: Research Articlementioning

confidence: 99%

“…Fourier series window (FSW) based pulse sequences have been used mostly for 31 P NMR in muscle and liver (10)(11)(12). The FSW is an alternative to traditional Fourier transform chemical shift imaging (CSI).…”

Section: Research Articlementioning

confidence: 99%

“…The FSW approach is thus ideally suited for applications that require many averages as is the case for 13 C NMR of glycogen. Therefore the aim of the present study was two-fold: first to implement a localization scheme based on the 2D Fourier series window to minimize CSD, and second to establish a dual-isotope protocol using [1,[6][7][8][9][10][11][12][13] C 2 ] glucose and to determine the Glyc turnover time while monitoring its concentration under light anesthesia.…”

Section: Research Articlementioning

confidence: 99%

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Quantification of brain glycogen concentration and turnover through localized ¹³C NMR of both the C1 and C6 resonances

et al. 2010

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We have recently shown that at isotopic steady state 13 C NMR can provide a direct measurement of glycogen concentration changes, but that the turnover of glycogen was not accessible with this protocol. The aim of the present study was to design, implement and apply a novel dual-tracer infusion protocol to simultaneously measure glycogen concentration and turnover. After reaching isotopic steady state for glycogen C1 using [1-13 C] glucose administration, [1,6-13 C 2 ] glucose was infused such that isotopic steady state was maintained at the C1 position, but the C6 position reflected 13 C label incorporation. To overcome the large chemical shift displacement error between the C1 and C6 resonances of glycogen, we implemented 2D gradient based localization using the Fourier series window approach, in conjunction with time-domain analysis of the resulting FIDs using jMRUI. The glycogen concentration of 5.1 W 1.6 mM measured from the C1 position was in excellent agreement with concomitant biochemical determinations. Glycogen turnover measured from the rate of label incorporation into the C6 position of glycogen in the a-chloralose anesthetized rat was 0.7 mmol/g/h.

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An efficient MR phosphorous spectroscopic localization technique for studying ischemic heart

Liu

Zhang

1999

J. Magn. Reson. Imaging

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Phase-modulated rotating-frame spectroscopic localization using an adiabatic plane-rotation pulse and a single surface coil

Cited by 31 publications

References 24 publications

Oxidative capacity in failing hearts

Oxidative capacity in failing hearts

Quantification of brain glycogen concentration and turnover through localized ¹³C NMR of both the C1 and C6 resonances

An efficient MR phosphorous spectroscopic localization technique for studying ischemic heart

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Phase-modulated rotating-frame spectroscopic localization using an adiabatic plane-rotation pulse and a single surface coil

Cited by 31 publications

References 24 publications

Oxidative capacity in failing hearts

Oxidative capacity in failing hearts

Quantification of brain glycogen concentration and turnover through localized 13C NMR of both the C1 and C6 resonances

An efficient MR phosphorous spectroscopic localization technique for studying ischemic heart

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Product

Resources

About

Quantification of brain glycogen concentration and turnover through localized ¹³C NMR of both the C1 and C6 resonances