OBJECTIVE: Magnesium regulates a large number of cellular processes.
Small changes in intracellular free Mg(2+) (Mg(2+)(i)) may have
important effects on cardiac excitability and contractility. We investigated
the effects of Mg(2+)(i) on cardiac excitation-contraction coupling.
METHODS: We used our ionic-metabolic model that incorporates equations
for Ca(2+) and Mg(2+) buffering and transport by ATP and ADP and
equations for MgATP regulation of ion transporters (Na(+)-K(+) pump,
sarcolemmal and sarcoplasmic Ca(2+) pumps). RESULTS: Model results
indicate that variations in cytosolic Mg(2+) level might sensitively
affect diastolic and systolic Ca(2+), sarcoplasmic Ca(2+) content,
Ca(2+) influx through L-type channels, efficiency of the Na(+)/Ca(2+)
exchanger and action potential shape. The analysis suggests that
the most important reason for the observed effects is a modified
normal function of sarcoplasmic Ca(2+)-ATPase pump by altered diastolic
MgATP levels. CONCLUSION: The model is able to reproduce qualitatively
a sequence of events that correspond well with experimental observations
during cardiac excitation-contraction coupling in mammalian ventricular
myocytes.
%0 Journal Article
%1 Mich_2004_514
%A Michailova, Anushka P
%A Belik, Mary Ellen
%A McCulloch, Andrew D
%D 2004
%J J Am Coll Nutr
%K ATPases ATPases; Action Adenosine Biological; Calcium, Calcium-Transporting Conductivity; Diphosphate, Electric Humans; Ion Magnesium, Models, Myocardium, Potentials; Pumps, Reticulum Reticulum; Sarcoplasmic Transport; Triphosphate, cytology/metabolism; metabolism;
%N 5
%P 514S--517S
%T Effects of magnesium on cardiac excitation-contraction coupling.
%V 23
%X OBJECTIVE: Magnesium regulates a large number of cellular processes.
Small changes in intracellular free Mg(2+) (Mg(2+)(i)) may have
important effects on cardiac excitability and contractility. We investigated
the effects of Mg(2+)(i) on cardiac excitation-contraction coupling.
METHODS: We used our ionic-metabolic model that incorporates equations
for Ca(2+) and Mg(2+) buffering and transport by ATP and ADP and
equations for MgATP regulation of ion transporters (Na(+)-K(+) pump,
sarcolemmal and sarcoplasmic Ca(2+) pumps). RESULTS: Model results
indicate that variations in cytosolic Mg(2+) level might sensitively
affect diastolic and systolic Ca(2+), sarcoplasmic Ca(2+) content,
Ca(2+) influx through L-type channels, efficiency of the Na(+)/Ca(2+)
exchanger and action potential shape. The analysis suggests that
the most important reason for the observed effects is a modified
normal function of sarcoplasmic Ca(2+)-ATPase pump by altered diastolic
MgATP levels. CONCLUSION: The model is able to reproduce qualitatively
a sequence of events that correspond well with experimental observations
during cardiac excitation-contraction coupling in mammalian ventricular
myocytes.
@article{Mich_2004_514,
abstract = {OBJECTIVE: Magnesium regulates a large number of cellular processes.
Small changes in intracellular free Mg(2+) ([Mg(2+)](i)) may have
important effects on cardiac excitability and contractility. We investigated
the effects of [Mg(2+)](i) on cardiac excitation-contraction coupling.
METHODS: We used our ionic-metabolic model that incorporates equations
for Ca(2+) and Mg(2+) buffering and transport by ATP and ADP and
equations for MgATP regulation of ion transporters (Na(+)-K(+) pump,
sarcolemmal and sarcoplasmic Ca(2+) pumps). RESULTS: Model results
indicate that variations in cytosolic Mg(2+) level might sensitively
affect diastolic and systolic Ca(2+), sarcoplasmic Ca(2+) content,
Ca(2+) influx through L-type channels, efficiency of the Na(+)/Ca(2+)
exchanger and action potential shape. The analysis suggests that
the most important reason for the observed effects is a modified
normal function of sarcoplasmic Ca(2+)-ATPase pump by altered diastolic
MgATP levels. CONCLUSION: The model is able to reproduce qualitatively
a sequence of events that correspond well with experimental observations
during cardiac excitation-contraction coupling in mammalian ventricular
myocytes.},
added-at = {2009-06-03T11:20:58.000+0200},
author = {Michailova, Anushka P and Belik, Mary Ellen and McCulloch, Andrew D},
biburl = {https://www.bibsonomy.org/bibtex/220186772590b71b4ff6c22cc1aa942ef/hake},
description = {The whole bibliography file I use.},
file = {Mich_2004_514.pdf:Mich_2004_514.pdf:PDF},
institution = {Department of Bioengineering, PFBH 241, University of California-San
Diego, 9500 Gilman Drive, La Jolla, CA 92093-0412, USA. amihaylo@bioeng.ucsd.edu},
interhash = {e8e3074e977338e8a76040fd7d6053e8},
intrahash = {20186772590b71b4ff6c22cc1aa942ef},
journal = {J Am Coll Nutr},
keywords = {ATPases ATPases; Action Adenosine Biological; Calcium, Calcium-Transporting Conductivity; Diphosphate, Electric Humans; Ion Magnesium, Models, Myocardium, Potentials; Pumps, Reticulum Reticulum; Sarcoplasmic Transport; Triphosphate, cytology/metabolism; metabolism;},
month = Oct,
number = 5,
pages = {514S--517S},
pdf = {Mich_2004_514.pdf},
pii = {23/5/514S},
pmid = {15466954},
timestamp = {2009-06-03T11:21:23.000+0200},
title = {Effects of magnesium on cardiac excitation-contraction coupling.},
volume = 23,
year = 2004
}