Document Detail

Role of MgADP in the development of diastolic dysfunction in the intact beating rat heart.
MedLine Citation:
PMID:  9045879     Owner:  NLM     Status:  MEDLINE    
Sarcomere relaxation depends on dissociation of actin and myosin, which is regulated by a number of factors, including intracellular [MgATP] as well as MgATP hydrolysis products [MgADP] and inorganic phosphate [Pi], pHi, and cytosolic calcium concentration ([Ca2+]c). To distinguish the contribution of MgADP from the other regulators in the development of diastolic dysfunction, we used a strategy to increase free [MgADP] without changing [MgATP], [Pi], or pHi. This was achieved by applying a low dose of iodoacetamide to selectively inhibit the creatine kinase activity in isolated perfused rat hearts. [MgATP], [MgADP], [Pi], and [H+] were determined using 31P NMR spectroscopy. The [Ca2+]c and the glycolytic rate were also measured. We observed an approximately threefold increase in left ventricular end diastolic pressure (LVEDP) and 38% increase in the time constant of pressure decay (P < 0.05) in these hearts, indicating a significant impairment of diastolic function. The increase in LVEDP was closely related to the increase in free [MgADP]. Rate of glycolysis was not changed, and [Ca2+]c increased by 16%, which cannot explain the severity of diastolic dysfunction. Thus, our data indicate that MgADP contributes significantly to diastolic dysfunction, possibly by slowing the rate of cross-bridge cycling.
R Tian; M E Christe; M Spindler; J C Hopkins; J M Halow; S A Camacho; J S Ingwall
Related Documents :
10070079 - Modulation of av nodal and hisian conduction by changes in extracellular space.
25161689 - The association of genetic variations with sensitivity of blood pressure to dietary sal...
25354779 - Current dietary salt intake of japanese individuals assessed during health check-up.
9045879 - Role of mgadp in the development of diastolic dysfunction in the intact beating rat heart.
7802299 - Effects of adenosine infusion on systolic and diastolic left ventricular function after...
9301479 - Effects of adenosine agonists on intraocular pressure and aqueous humor dynamics in cyn...
37349 - Pressor response during cystomanometry in spinal injury patients complicated with detru...
3318269 - Hemodynamic effects of high frequency ventilation superimposed on intermittent positive...
19893499 - Dietary protein level interacts with omega-3 polyunsaturated fatty acid deficiency to i...
Publication Detail:
Type:  Journal Article; Research Support, Non-U.S. Gov't; Research Support, U.S. Gov't, P.H.S.    
Journal Detail:
Title:  The Journal of clinical investigation     Volume:  99     ISSN:  0021-9738     ISO Abbreviation:  J. Clin. Invest.     Publication Date:  1997 Feb 
Date Detail:
Created Date:  1997-03-20     Completed Date:  1997-03-20     Revised Date:  2009-11-18    
Medline Journal Info:
Nlm Unique ID:  7802877     Medline TA:  J Clin Invest     Country:  UNITED STATES    
Other Details:
Languages:  eng     Pagination:  745-51     Citation Subset:  AIM; IM    
NMR Laboratory for Physiological Chemistry, Department of Medicine, Brigham and Women's Hospital, Boston, Massachusetts 02115, USA.
Export Citation:
APA/MLA Format     Download EndNote     Download BibTex
MeSH Terms
Adenosine Diphosphate / metabolism,  physiology*
Calcium / metabolism
Dose-Response Relationship, Drug
Iodoacetamide / pharmacology
Magnetic Resonance Spectroscopy
Myocardial Reperfusion
Myocardium / enzymology
Ventricular Dysfunction, Left / etiology*,  metabolism,  physiopathology*
Grant Support
Reg. No./Substance:
144-48-9/Iodoacetamide; 58-64-0/Adenosine Diphosphate; 7440-70-2/Calcium

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine

Previous Document:  Shear stress induction of the tissue factor gene.
Next Document:  Identification of type-specific cytotoxic T lymphocyte responses to homologous viral proteins in lab...