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Title: Complete inhibition of creatine kinase in isolated perfused rat hearts

Abstract

Transient exposure of an isolated isovolumic perfused rat heart to low concentrations (0.5 mM) of perfusate-born iodoacetamide resulted in complete inhibition of creatine kinase and partial inhibition of glyceraldehyde-3-phosphate dehydrogenase in the heart. At low levels of developed pressure, hearts maintained mechanical function, ATP, and creatine phosphate levels at control values. However, iodoacetamide-inhibited hearts were unable to maintain control values of end diastolic pressure or peak systolic pressure as work load increased. Global ischemia resulted in loss of all ATP without loss of creatine phosphate, indicating lack of active creatine kinase. These results indicate that isovolumic perfused rat hearts are able to maintain normal function and normal levels of high-energy phosphates without active creatine kinase at low levels of developed pressure. /sup 31/P-NMR of the heart was carried out.

Authors:
;
Publication Date:
Research Org.:
Harvard Medical School, Boston, MA
OSTI Identifier:
6352364
Resource Type:
Journal Article
Resource Relation:
Journal Name: Am. J. Physiol.; (United States); Journal Volume: 252:1
Country of Publication:
United States
Language:
English
Subject:
62 RADIOLOGY AND NUCLEAR MEDICINE; HEART; NUCLEAR MAGNETIC RESONANCE; PHOSPHOTRANSFERASES; BIOCHEMISTRY; INHIBITION; ACETAMIDE; BLOOD PRESSURE; CREATINE; HEMIACETAL DEHYDROGENASES; ISCHEMIA; NMR SPECTRA; ORGANIC IODINE COMPOUNDS; PERFUSED TISSUES; PHOSPHORUS 31; RATS; AMIDES; AMINO ACIDS; ANIMAL TISSUES; ANIMALS; BODY; CARBOXYLIC ACIDS; CARDIOVASCULAR DISEASES; CARDIOVASCULAR SYSTEM; CHEMISTRY; DISEASES; ENZYMES; ISOTOPES; LIGHT NUCLEI; MAGNETIC RESONANCE; MAMMALS; NUCLEI; ODD-EVEN NUCLEI; ORGANIC ACIDS; ORGANIC COMPOUNDS; ORGANIC HALOGEN COMPOUNDS; ORGANIC NITROGEN COMPOUNDS; ORGANS; OXIDOREDUCTASES; PHOSPHORUS ISOTOPES; PHOSPHORUS-GROUP TRANSFERASES; RESONANCE; RODENTS; SPECTRA; STABLE ISOTOPES; TISSUES; TRANSFERASES; VASCULAR DISEASES; VERTEBRATES; 550601* - Medicine- Unsealed Radionuclides in Diagnostics

Citation Formats

Fossel, E.T., and Hoefeler, H. Complete inhibition of creatine kinase in isolated perfused rat hearts. United States: N. p., 1987. Web.
Fossel, E.T., & Hoefeler, H. Complete inhibition of creatine kinase in isolated perfused rat hearts. United States.
Fossel, E.T., and Hoefeler, H. Thu . "Complete inhibition of creatine kinase in isolated perfused rat hearts". United States. doi:.
@article{osti_6352364,
title = {Complete inhibition of creatine kinase in isolated perfused rat hearts},
author = {Fossel, E.T. and Hoefeler, H.},
abstractNote = {Transient exposure of an isolated isovolumic perfused rat heart to low concentrations (0.5 mM) of perfusate-born iodoacetamide resulted in complete inhibition of creatine kinase and partial inhibition of glyceraldehyde-3-phosphate dehydrogenase in the heart. At low levels of developed pressure, hearts maintained mechanical function, ATP, and creatine phosphate levels at control values. However, iodoacetamide-inhibited hearts were unable to maintain control values of end diastolic pressure or peak systolic pressure as work load increased. Global ischemia resulted in loss of all ATP without loss of creatine phosphate, indicating lack of active creatine kinase. These results indicate that isovolumic perfused rat hearts are able to maintain normal function and normal levels of high-energy phosphates without active creatine kinase at low levels of developed pressure. /sup 31/P-NMR of the heart was carried out.},
doi = {},
journal = {Am. J. Physiol.; (United States)},
number = ,
volume = 252:1,
place = {United States},
year = {Thu Jan 01 00:00:00 EST 1987},
month = {Thu Jan 01 00:00:00 EST 1987}
}
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