| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
(Circulation. 2001;104:1844.)
© 2001 American Heart Association, Inc.
Basic Science Reports |
From the Medizinische Universitätsklinik, Würzburg University, Germany (M.H., H.R., H.S., C.D., S.N.); Wallenberg Laboratory, Sahlgrenska Hospital, Gothenburg University, Sweden (M.H.); and the Department of Cardiovascular Medicine, John Radcliffe Hospital, University of Oxford, UK (S.N.).
Correspondence to Michael Horn, PhD, Sahlgrenska Sjukhuset, Wallenberg Laboratoriet, 41345 Göteborg, Sweden. E-mail m.horn{at}wlab.gu.se
Background The failing myocardium is characterized by reductions of phosphocreatine (PCr) and free creatine content and by decreases of energy reserve via creatine kinase (CK), ie, CK reaction velocity (FluxCK). It has remained unclear whether these changes contribute directly to contractile dysfunction. In the present study, myocardial PCr stores in a heart failure model were further depleted by feeding of the PCr analogue ß-guanidinopropionate (GP). Functional and metabolic consequences were studied.
Methods and Results Rats were subjected to sham operation or left coronary artery ligation (MI). Surviving rats were assigned to 4 groups and fed with 0% (n=7, Sham; n=5, MI) or 1% (n=7 Sham+GP, n=8 MI+GP) GP. Two additional groups were fed GP for 2 or 4 weeks before MI. After 8 weeks, hearts were isolated and perfused, and left ventricular pressure-volume curves were obtained. High-energy phosphate metabolism was determined with 31P NMR spectroscopy. After GP feeding or MI, left ventricular pressure-volume curves were depressed by 33% and 32%, respectively, but GP feeding in MI hearts did not further impair mechanical function. Both MI and GP feeding reduced PCr content and FluxCK, but here, effects were additive. In MI+GP rats, PCr levels and FluxCK were reduced by 87% and 94%, respectively. Although ATP levels were maintained in the GP and MI groups, ATP content was reduced by 18% in MI+GP hearts. Furthermore, 24-hour mortality in GP-prefed rats was 100%.
Conclusions Rats with an 87% predepletion of myocardial PCr content cannot survive an acute MI. Chronically infarcted hearts subjected to additional PCr depletion cannot maintain ATP homeostasis.
Key Words: magnetic resonance imaging spectroscopy heart failure myocardial infarction creatine kinase
This article has been cited by other articles:
![]() |
V. A. Selivanov, S. Krause, J. Roca, and M. Cascante Modeling of Spatial Metabolite Distributions in the Cardiac Sarcomere Biophys. J., May 15, 2007; 92(10): 3492 - 3500. [Abstract] [Full Text] [PDF] |
||||
![]() |
C. S. Smith, P. A. Bottomley, S. P. Schulman, G. Gerstenblith, and R. G. Weiss Altered Creatine Kinase Adenosine Triphosphate Kinetics in Failing Hypertrophied Human Myocardium Circulation, September 12, 2006; 114(11): 1151 - 1158. [Abstract] [Full Text] [PDF] |
||||
![]() |
A. J. Murray, C. A. Lygate, M. A. Cole, C. A. Carr, G. K. Radda, S. Neubauer, and K. Clarke Insulin resistance, abnormal energy metabolism and increased ischemic damage in the chronically infarcted rat heart Cardiovasc Res, July 1, 2006; 71(1): 149 - 157. [Abstract] [Full Text] [PDF] |
||||
![]() |
A. V. Naumova, V. P. Chacko, R. Ouwerkerk, L. Stull, E. Marban, and R. G. Weiss Xanthine oxidase inhibitors improve energetics and function after infarction in failing mouse hearts Am J Physiol Heart Circ Physiol, February 1, 2006; 290(2): H837 - H843. [Abstract] [Full Text] [PDF] |
||||
![]() |
M. ten Hove, C. A. Lygate, A. Fischer, J. E. Schneider, A. E. Sang, K. Hulbert, L. Sebag-Montefiore, H. Watkins, K. Clarke, D. Isbrandt, et al. Reduced Inotropic Reserve and Increased Susceptibility to Cardiac Ischemia/Reperfusion Injury in Phosphocreatine-Deficient Guanidinoacetate-N-Methyltransferase-Knockout Mice Circulation, May 17, 2005; 111(19): 2477 - 2485. [Abstract] [Full Text] [PDF] |
||||
![]() |
M. Nahrendorf, M. Spindler, K. Hu, L. Bauer, O. Ritter, P. Nordbeck, T. Quaschning, K.-H. Hiller, J. Wallis, G. Ertl, et al. Creatine kinase knockout mice show left ventricular hypertrophy and dilatation, but unaltered remodeling post-myocardial infarction Cardiovasc Res, February 1, 2005; 65(2): 419 - 427. [Abstract] [Full Text] [PDF] |
||||
![]() |
J. S. Ingwall and R. G. Weiss Is the Failing Heart Energy Starved?: On Using Chemical Energy to Support Cardiac Function Circ. Res., July 23, 2004; 95(2): 135 - 145. [Abstract] [Full Text] [PDF] |
||||
![]() |
P.A. Poole-Wilson Who are the enemies? Lack of oxygen Eur. Heart J. Suppl., November 1, 2002; 4(suppl_G): G15 - G19. [Abstract] [PDF] |
||||
|
Circulation Home | Subscriptions | Archives | Feedback | Authors | Help | AHA Journals Home | Search Copyright © 2001 American Heart Association, Inc. All rights reserved. Unauthorized use prohibited. |