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Previs MJ, O’Leary TS, Morley MP, Palmer B, LeWinter M, Yob J, Pagani FD, Petucci C, Kim MS, Margulies KB, Arany Z, Kelly DP, Day SM. Defects in the Proteome and Metabolome in Human Hypertrophic Cardiomyopathy. Circ Heart Fail 2022; 15:e009521. [PMID: 35543134 PMCID: PMC9708114 DOI: 10.1161/circheartfailure.121.009521] [Citation(s) in RCA: 32] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
BACKGROUND Defects in energetics are thought to be central to the pathophysiology of hypertrophic cardiomyopathy (HCM); yet, the determinants of ATP availability are not known. The purpose of this study is to ascertain the nature and extent of metabolic reprogramming in human HCM, and its potential impact on contractile function. METHODS We conducted proteomic and targeted, quantitative metabolomic analyses on heart tissue from patients with HCM and from nonfailing control human hearts. RESULTS In the proteomic analysis, the greatest differences observed in HCM samples compared with controls were increased abundances of extracellular matrix and intermediate filament proteins and decreased abundances of muscle creatine kinase and mitochondrial proteins involved in fatty acid oxidation. These differences in protein abundance were coupled with marked reductions in acyl carnitines, byproducts of fatty acid oxidation, in HCM samples. Conversely, the ketone body 3-hydroxybutyrate, branched chain amino acids, and their breakdown products, were all significantly increased in HCM hearts. ATP content, phosphocreatine, nicotinamide adenine dinucleotide and its phosphate derivatives, NADP and NADPH, and acetyl CoA were also severely reduced in HCM compared with control hearts. Functional assays performed on human skinned myocardial fibers demonstrated that the magnitude of observed reduction in ATP content in the HCM samples would be expected to decrease the rate of cross-bridge detachment. Moreover, left atrial size, an indicator of diastolic compliance, was inversely correlated with ATP content in hearts from patients with HCM. CONCLUSIONS HCM hearts display profound deficits in nucleotide availability with markedly reduced capacity for fatty acid oxidation and increases in ketone bodies and branched chain amino acids. These results have important therapeutic implications for the future design of metabolic modulators to treat HCM.
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Affiliation(s)
- Michael J. Previs
- Department of Molecular Physiology and Biophysics, University of Vermont, Larner College of Medicine
| | - Thomas S. O’Leary
- Department of Molecular Physiology and Biophysics, University of Vermont, Larner College of Medicine
| | - Michael P. Morley
- Division of Cardiovascular Medicine and the Penn Cardiovascular Institute, Perelman School of Medicine, University of Pennsylvania
| | - Brad Palmer
- Department of Molecular Physiology and Biophysics, University of Vermont, Larner College of Medicine
| | - Martin LeWinter
- Department of Molecular Physiology and Biophysics, University of Vermont, Larner College of Medicine
| | - Jaime Yob
- Division of Cardiovascular Medicine and the Penn Cardiovascular Institute, Perelman School of Medicine, University of Pennsylvania
| | - Francis D. Pagani
- Department of Cardiothoracic Surgery, University of Michigan School of Medicine
| | - Christopher Petucci
- Division of Cardiovascular Medicine and the Penn Cardiovascular Institute, Perelman School of Medicine, University of Pennsylvania
| | - Min-Soo Kim
- Division of Cardiovascular Medicine and the Penn Cardiovascular Institute, Perelman School of Medicine, University of Pennsylvania
| | - Kenneth B. Margulies
- Division of Cardiovascular Medicine and the Penn Cardiovascular Institute, Perelman School of Medicine, University of Pennsylvania
| | - Zoltan Arany
- Division of Cardiovascular Medicine and the Penn Cardiovascular Institute, Perelman School of Medicine, University of Pennsylvania
| | - Daniel P. Kelly
- Division of Cardiovascular Medicine and the Penn Cardiovascular Institute, Perelman School of Medicine, University of Pennsylvania
| | - Sharlene M. Day
- Division of Cardiovascular Medicine and the Penn Cardiovascular Institute, Perelman School of Medicine, University of Pennsylvania
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Burger N, James AM, Mulvey JF, Hoogewijs K, Ding S, Fearnley IM, Loureiro-López M, Norman AAI, Arndt S, Mottahedin A, Sauchanka O, Hartley RC, Krieg T, Murphy MP. ND3 Cys39 in complex I is exposed during mitochondrial respiration. Cell Chem Biol 2022; 29:636-649.e14. [PMID: 34739852 PMCID: PMC9076552 DOI: 10.1016/j.chembiol.2021.10.010] [Citation(s) in RCA: 24] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2021] [Revised: 07/21/2021] [Accepted: 10/07/2021] [Indexed: 12/13/2022]
Abstract
Mammalian complex I can adopt catalytically active (A-) or deactive (D-) states. A defining feature of the reversible transition between these two defined states is thought to be exposure of the ND3 subunit Cys39 residue in the D-state and its occlusion in the A-state. As the catalytic A/D transition is important in health and disease, we set out to quantify it by measuring Cys39 exposure using isotopic labeling and mass spectrometry, in parallel with complex I NADH/CoQ oxidoreductase activity. To our surprise, we found significant Cys39 exposure during NADH/CoQ oxidoreductase activity. Furthermore, this activity was unaffected if Cys39 alkylation occurred during complex I-linked respiration. In contrast, alkylation of catalytically inactive complex I irreversibly blocked the reactivation of NADH/CoQ oxidoreductase activity by NADH. Thus, Cys39 of ND3 is exposed in complex I during mitochondrial respiration, with significant implications for our understanding of the A/D transition and the mechanism of complex I.
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Affiliation(s)
- Nils Burger
- Medical Research Council-Mitochondrial Biology Unit, University of Cambridge, Cambridge CB2 0XY, UK
| | - Andrew M James
- Medical Research Council-Mitochondrial Biology Unit, University of Cambridge, Cambridge CB2 0XY, UK
| | - John F Mulvey
- Department of Medicine, University of Cambridge, Addenbrooke's Hospital, Cambridge CB2 0QQ, UK
| | - Kurt Hoogewijs
- Medical Research Council-Mitochondrial Biology Unit, University of Cambridge, Cambridge CB2 0XY, UK; The Wellcome Trust Centre for Mitochondrial Research, Institute for Cell and Molecular Biosciences, Newcastle University, Newcastle Upon Tyne NE2 4HH, UK; Medical Research Council-Laboratory of Molecular Biology, Cambridge CB2 0QH, UK
| | - Shujing Ding
- Medical Research Council-Mitochondrial Biology Unit, University of Cambridge, Cambridge CB2 0XY, UK
| | - Ian M Fearnley
- Medical Research Council-Mitochondrial Biology Unit, University of Cambridge, Cambridge CB2 0XY, UK
| | - Marta Loureiro-López
- Medical Research Council-Mitochondrial Biology Unit, University of Cambridge, Cambridge CB2 0XY, UK
| | | | - Sabine Arndt
- Medical Research Council-Mitochondrial Biology Unit, University of Cambridge, Cambridge CB2 0XY, UK
| | - Amin Mottahedin
- Medical Research Council-Mitochondrial Biology Unit, University of Cambridge, Cambridge CB2 0XY, UK; Department of Medicine, University of Cambridge, Addenbrooke's Hospital, Cambridge CB2 0QQ, UK; Department of Physiology, Institute of Neuroscience and Physiology, Sahlgrenska Academy, University of Gothenburg, 405 30 Gothenburg, Sweden
| | - Olga Sauchanka
- Department of Medicine, University of Cambridge, Addenbrooke's Hospital, Cambridge CB2 0QQ, UK
| | | | - Thomas Krieg
- Department of Medicine, University of Cambridge, Addenbrooke's Hospital, Cambridge CB2 0QQ, UK
| | - Michael P Murphy
- Medical Research Council-Mitochondrial Biology Unit, University of Cambridge, Cambridge CB2 0XY, UK.
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Ahearne M, Coyle A. Application of UVA-riboflavin crosslinking to enhance the mechanical properties of extracellular matrix derived hydrogels. J Mech Behav Biomed Mater 2015; 54:259-67. [PMID: 26476968 DOI: 10.1016/j.jmbbm.2015.09.035] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2015] [Revised: 09/23/2015] [Accepted: 09/30/2015] [Indexed: 01/22/2023]
Abstract
Hydrogels derived from extracellular matrix (ECM) have become increasing popular in recent years, particularly for use in tissue engineering. One limitation with ECM hydrogels is that they tend to have poor mechanical properties compared to native tissues they are trying to replicate. To address this problem, a UVA (ultraviolet-A) riboflavin crosslinking technique was applied to ECM hydrogels to determine if it could be used to improve their elastic modulus. Hydrogels fabricated from corneal, cardiac and liver ECM were used in this study. The mechanical properties of the hydrogels were characterized using a spherical indentation technique. The microstructure of the hydrogels and the cytotoxic effect of crosslinking on cell seeded hydrogels were also evaluated. The combination of UVA light and riboflavin solution led to a significant increase in elastic modulus from 6.8kPa to 24.7kPa, 1.4kPa to 6.9kPa and 0.9kPa to 1.6kPa for corneal, cardiac and liver ECM hydrogels respectively. The extent of this increase was dependent on a number of factors including the UVA exposure time and the initial hydrogel concentration. There were also a high percentage of viable cells within the cell seeded hydrogels with 94% of cells remaining viable after 90min exposure to UVA light. These results suggest that UVA-riboflavin crosslinking is an effective approach for improving the mechanical properties of ECM hydrogels without resulting in a significant reduction of cell viability.
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Affiliation(s)
- Mark Ahearne
- Trinity Centre for Bioengineering, Trinity Biomedical Sciences Institute, Trinity College Dublin, Ireland; Department of Mechanical and Manufacturing Engineering, School of Engineering, Trinity College Dublin, Ireland.
| | - Aron Coyle
- Trinity Centre for Bioengineering, Trinity Biomedical Sciences Institute, Trinity College Dublin, Ireland; Department of Mechanical and Manufacturing Engineering, School of Engineering, Trinity College Dublin, Ireland
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Chang AN, Battiprolu PK, Cowley PM, Chen G, Gerard RD, Pinto JR, Hill JA, Baker AJ, Kamm KE, Stull JT. Constitutive phosphorylation of cardiac myosin regulatory light chain in vivo. J Biol Chem 2015; 290:10703-16. [PMID: 25733667 DOI: 10.1074/jbc.m115.642165] [Citation(s) in RCA: 51] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2015] [Indexed: 01/03/2023] Open
Abstract
In beating hearts, phosphorylation of myosin regulatory light chain (RLC) at a single site to 0.45 mol of phosphate/mol by cardiac myosin light chain kinase (cMLCK) increases Ca(2+) sensitivity of myofilament contraction necessary for normal cardiac performance. Reduction of RLC phosphorylation in conditional cMLCK knock-out mice caused cardiac dilation and loss of cardiac performance by 1 week, as shown by increased left ventricular internal diameter at end-diastole and decreased fractional shortening. Decreased RLC phosphorylation by conventional or conditional cMLCK gene ablation did not affect troponin-I or myosin-binding protein-C phosphorylation in vivo. The extent of RLC phosphorylation was not changed by prolonged infusion of dobutamine or treatment with a β-adrenergic antagonist, suggesting that RLC is constitutively phosphorylated to maintain cardiac performance. Biochemical studies with myofilaments showed that RLC phosphorylation up to 90% was a random process. RLC is slowly dephosphorylated in both noncontracting hearts and isolated cardiac myocytes from adult mice. Electrically paced ventricular trabeculae restored RLC phosphorylation, which was increased to 0.91 mol of phosphate/mol of RLC with inhibition of myosin light chain phosphatase (MLCP). The two RLCs in each myosin appear to be readily available for phosphorylation by a soluble cMLCK, but MLCP activity limits the amount of constitutive RLC phosphorylation. MLCP with its regulatory subunit MYPT2 bound tightly to myofilaments was constitutively phosphorylated in beating hearts at a site that inhibits MLCP activity. Thus, the constitutive RLC phosphorylation is limited physiologically by low cMLCK activity in balance with low MLCP activity.
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Affiliation(s)
| | | | - Patrick M Cowley
- the Veterans Affairs Medical Center, San Francisco, California 94143, the University of California, San Francisco, California 94143, and
| | | | - Robert D Gerard
- Molecular Biology, University of Texas Southwestern Medical Center, Dallas, Texas 75390
| | - Jose R Pinto
- the Department of Biomedical Sciences, Florida State University College of Medicine, Tallahassee, Florida 32306
| | - Joseph A Hill
- Internal Medicine (Cardiology), and Molecular Biology, University of Texas Southwestern Medical Center, Dallas, Texas 75390
| | - Anthony J Baker
- the Veterans Affairs Medical Center, San Francisco, California 94143, the University of California, San Francisco, California 94143, and
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Phillips D, Covian R, Aponte AM, Glancy B, Taylor JF, Chess D, Balaban RS. Regulation of oxidative phosphorylation complex activity: effects of tissue-specific metabolic stress within an allometric series and acute changes in workload. Am J Physiol Regul Integr Comp Physiol 2012; 302:R1034-48. [PMID: 22378775 DOI: 10.1152/ajpregu.00596.2011] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
The concentration of mitochondrial oxidative phosphorylation complexes (MOPCs) is tuned to the maximum energy conversion requirements of a given tissue; however, whether the activity of MOPCs is altered in response to acute changes in energy conversion demand is unclear. We hypothesized that MOPCs activity is modulated by tissue metabolic stress to maintain the energy-metabolism homeostasis. Metabolic stress was defined as the observed energy conversion rate/maximum energy conversion rate. The maximum energy conversion rate was assumed to be proportional to the concentration of MOPCs, as determined with optical spectroscopy, gel electrophoresis, and mass spectrometry. The resting metabolic stress of the heart and liver across the range of resting metabolic rates within an allometric series (mouse, rabbit, and pig) was determined from MPOCs content and literature respiratory values. The metabolic stress of the liver was high and nearly constant across the allometric series due to the proportional increase in MOPCs content with resting metabolic rate. In contrast, the MOPCs content of the heart was essentially constant in the allometric series, resulting in an increasing metabolic stress with decreasing animal size. The MOPCs activity was determined in native gels, with an emphasis on Complex V. Extracted MOPCs enzyme activity was proportional to resting metabolic stress across tissues and species. Complex V activity was also shown to be acutely modulated by changes in metabolic stress in the heart, in vivo and in vitro. The modulation of extracted MOPCs activity suggests that persistent posttranslational modifications (PTMs) alter MOPCs activity both chronically and acutely, specifically in the heart. Protein phosphorylation of Complex V was correlated with activity inhibition under several conditions, suggesting that protein phosphorylation may contribute to activity modulation with energy metabolic stress. These data are consistent with the notion that metabolic stress modulates MOPCs activity in the heart.
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Affiliation(s)
- Darci Phillips
- Laboratory of Cardiac Energetics, NHLBI, NIH, Bethesda, MD 20892-1061, USA
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REGAN TJ, CHRISTENSEN RC, WADA T, TALMERS FN, HELLEMS HK. Myocardial response to acetyl strophanthidin in congestive heart failure; a study of electrolytes and carbohydrate substrates. J Clin Invest 2000; 38:306-16. [PMID: 13631061 PMCID: PMC293157 DOI: 10.1172/jci103803] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
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DAVIS JO, CARROLL WR, TRAPASSO M, YANKOPOULOS NA. Chemical characterization of cardiac myosin from normal dogs and from dogs with chronic congestive heart failure. J Clin Invest 1998; 39:1463-71. [PMID: 13720201 PMCID: PMC293392 DOI: 10.1172/jci104165] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
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DAVIS JO, TRAPASSO M, YANKOPOULOS NA. Studies of actomyosin from cardiac muscle of dogs with experimental congestive heart failure. Circ Res 1998; 7:957-68. [PMID: 13814479 DOI: 10.1161/01.res.7.6.957] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Comparative studies were made on cardiac actomyosin from normal dogs and from dogs with experimental failure. Actomyosin was characterized by ultracentrifugal sedimentation velocity, viscosity and ATP-ase measurements. The data on actomyosin from normal cardiac muscle showed a striking similarity to the findings reported by others for skeletal muscle actomyosin. The only difference found between cardiac actomyosin front the normal and experimental material was an abnormal component ( S
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= 5.0-6.7) in the sedimentation pattern for actomyosin from 4 of 11 dogs with cardiac failure. It seems likely that the changes in actomyosin which resulted in the abnormal sedimentation pattern were produced during extraction or preparation of the actomyosin and that they do not reflect an altered state of actomyosin in the functioning heart. The explanation for the occurrence of this slow sedimentation component solely in the experimental material is not clear.
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Abstract
The adult rat's ventricular myocardium is able to increase its mass markedly while maintaining its unit quality. It does so by maintaining constant the design of the sarcomeres: an increase in length is accomplished by the addition of sarcomeres in series; an increase in tension production is accomplished by the addition of more cross-sectional area of a uniform quality. This was shown by the almost constant concentration of the contractile protein, actomyosin, as well as by the histologic evidence of the constancy in the sarcomere lengths. Functional support was obtained by the finding of an identity in the parameters of the length-tension curves; the curves differed only in the absolute magnitude of the tensions, a difference that completely disappeared when suitable corrections were made for the size of the muscle. The electrical parameters also indicated a lack of change in the quality of the excitatory membrane phenomena. However, some data were presented that suggest that the myocardium may show altered properties dependent on the age of the animal. No evidence was found in support of the concept of detrimental consequences at least with this degree of cardiomegaly. It is rather concluded that this degree of cardiomegaly is accomplished without change in the basic architecture, properties, or concentration of the contractile mechanism.
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Abstract
Chronic congestive heart failure has been produced in dogs by surgical induction of valvular disease. Cardiac myosin was isolated from the normal dogs and from dogs with congestive heart failure and characterized. Physicochemical properties of the cardiac myosins were determined by measurements of velocity sedimentation, partial specific volume, rate of diffusion, limiting viscosity number, light-scattering behavior, and ATPase activity. The measurements show that normal cardiac myosin (myosin C) has a molecular weight of 225,000, whereas myosin from the failing heart (myosin F) has a molecular weight of 690,000. This change in molecular weight occurs without a marked alteration in amino acid composition and suggests that end-to-end trimerization of normal cardiac myosin occurs in association with congestive heart failure in the dog. There was no significant change in ATPase activity.
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Alpert NR, Mulieri LA, Litten RZ. Functional significance of altered myosin adenosine triphosphatase activity in enlarged hearts. Am J Cardiol 1979; 44:946-53. [PMID: 158969 DOI: 10.1016/0002-9149(79)90227-3] [Citation(s) in RCA: 70] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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Abstract
This review has pointed out the good correlation frequently observed between ATPase activity of various contractile protein preparations and contractile function of various muscles including the myocardium. Some of the variables in the measurement of the various ATPases and the relationship of these measurements to physiological ATPase in the intact myofibril have been mentioned. The possible roles of changes in the light chains of sulfhydryl groups in the control of ATPase activity have been outlined. The possibility that phosphorylating reactions might exert control over physiological activity remains to be clarified. It is evident that, despite the large amount of research that has been done, our understanding of how the biochemistry of contractile proteins relates to physiological function is in its infancy, and only with a more complete elucidation of the underlying biochemistry of the components of contractile proteins of physiological and pathophysiological adaptations become evident.
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Schwartz A, Sordahl LA, Entman ML, Allen JC, Reddy YS, Goldstein MA, Luchi RJ, Wyborny LE. Abnormal biochemistry in myocardial failure. Am J Cardiol 1973; 32:407-22. [PMID: 4354110 DOI: 10.1016/s0002-9149(73)80031-1] [Citation(s) in RCA: 71] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
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[The significance of creatine phosphate and adenosine triphosphate in terms of energy production, transport and utilization in the healthy and insufficient heart muscle]. KLINISCHE WOCHENSCHRIFT 1970; 48:332-41. [PMID: 4938632 DOI: 10.1007/bf01484859] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
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Gertz EW, Hess ML, Lain RF, Briggs FN. Activity of the vesicular calcium pump in the spontaneously failing heart-lung preparation. Circ Res 1967; 20:477-84. [PMID: 6057681 DOI: 10.1161/01.res.20.5.477] [Citation(s) in RCA: 58] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
The in vitro calcium uptake activity has been examined in fragments of sarcoplasmic reticulum, i.e. vesicles, obtained from hearts spontaneously failing in the canine heart-lung preparation. The rate of uptake was found to be less than that observed for vesicles from control hearts. If the vesicles were prepared from a failed heart that had been treated in vivo with ouabain, then the rate of calcium uptake was normal. In vitro additions of ouabain increased the rate of calcium uptake only with vesicles prepared from failing hearts. This effect of ouabain on calcium uptake by vesicles appears, therefore, to be specific for the defect causing depression of calcium uptake. No evidence could be found that the depression of calcium uptake is due to uncoupling of the pump adenosine triphosphatase. Calcium uptake and adenosine triphosphatase activity were found to be proportionately depressed in the failing heart and proportionately restored by ouabain.
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KIEN GA, SHERROD TR. The Effect of Digoxin on the Intermediary Metabolism of the Heart as Measured by Glucose-C
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Utilization in the Intact Dog. Circ Res 1960; 8:188-98. [PMID: 14408982 DOI: 10.1161/01.res.8.1.188] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Administration of a therapeutic dose level of digoxin in the intact dog resulted in an augmentation of the glucose utilization of the myocardium accompanied by a greatly increased rate of glycolytic and oxidative activity. The contribution of glucose to the total metabolism of the heart was increased, and the utilization of noncarbohydrate substrates was decreased. These metabolic changes occurred in the absence of changes in the dynamic functions of the heart, indicating that the metabolic alterations were due to a primary effect of the drug rather than an effect secondary to an altered state of cardiac activity.
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YANKOPOULOS NA, DAVIS JO, McFARLAND JA, HOLMAN J. Physiologic Changes during Chronic Congestive Heart Failure in Dogs with Tricuspid Insufficiency and Pulmonic Stenosis. Circ Res 1959; 7:950-6. [PMID: 13846448 DOI: 10.1161/01.res.7.6.950] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
chronic congestive heart failure was studied in dogs with surgically-produced tricuspid insufficiency and pulmonic stenosis. Ascites formed in association with an elevation in mean right atrial pressure. The volume of ascitic fluid and the rate of urinary sodium excretion varied greatly in individual dogs during the course of congestive failure and among the different animals. Sodium retention was most common but periods of sodium balance and natriuresis occurred. Comparative data on the right and left ventricles were obtained from determinations of intracardiac pressures, measurements of ventricular muscle mass at the time of sacrifice and studies of the lungs for evidence of chronic passive congestion. There was significant right ventricular hypertrophy but no evidence of left ventricular hypertrophy or failure.
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KAKO K, BING RJ. CONTRACTILITY OF ACTOMYOSIN BANDS PREPARED FROM NORMAL AND FAILING HUMAN HEARTS 1. J Clin Invest 1958; 37:465-70. [PMID: 13513777 PMCID: PMC293106 DOI: 10.1172/jci103626] [Citation(s) in RCA: 47] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
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BENSON ES, HALLAWAY BE, TURBAK CE. Contractile properties of glycerolextracted muscle bundles from the chronically failing canine heart. Circ Res 1958; 6:122-8. [PMID: 13500565 DOI: 10.1161/01.res.6.1.122] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Chronic congestive heart failure was induced in dogs by the surgical production of tricuspid insufficiency and pulmonary stenosis. Glycerol-extracted trabecular bundles from the right and left ventricles of these dogs developed significantly less tension than did similar preparations from the hearts of normal dogs. The maximum working capacity of the bundles from failing hearts was lower than that of bundles from normal hearts, hut the rate of hydrolysis of adenosinetriphosphate was the same as that of normal heart preparations. Since glycerol-extracted muscle bundles retain the basic contractile properties of fresh, surviving whole muscle but are free from membrane, neurohormonal, ionic and pH effects and are isolated from energy-supplying systems of muscle, defective contractility and decreased working capacity of muscle bundles from failing hearts may be appropriately ascribed to physiochemical changes in the contractile protein, actomyosin. Such alterations are undoubtedly of structural significance, and are related to the conformation changes in actomyosin which characterize the contractile cycle of muscle.
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HELLEMS HK, REGAN TJ, TALMERS FN. Myocardial transfer of sodium and potassium: effect of acetyl strophanthidin in normal dogs. J Clin Invest 1956; 35:1220-8. [PMID: 13376715 PMCID: PMC441700 DOI: 10.1172/jci103377] [Citation(s) in RCA: 42] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
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