%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 }