Saltatory propagation of Ca2+ waves by Ca2+ sparks
Punctate releases of Ca2+, called Ca2+ sparks, originate at the regular array of t-tubules in cardiac myocytes and skeletal muscle. During Ca2+ overload sparks serve as sites for the initiation and propagation of Ca2+ waves in myocytes. Computer simulations of spark-mediated waves are performed with...
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todo:paper_00063495_v75_n2_p595_Keizer2023-10-03T14:05:05Z Saltatory propagation of Ca2+ waves by Ca2+ sparks Keizer, J. Smith, G.D. Ponce-Dawson, S. Pearson, J.E. article calcium transport computer simulation diffusion coefficient fluorescence heart muscle cell nonhuman skeletal muscle transverse tubular system animal biological model cell membrane diffusion heart muscle kinetics metabolism skeletal muscle calcium ryanodine receptor Animals Calcium Cell Membrane Computer Simulation Diffusion Kinetics Models, Biological Muscle, Skeletal Myocardium Ryanodine Receptor Calcium Release Channel Punctate releases of Ca2+, called Ca2+ sparks, originate at the regular array of t-tubules in cardiac myocytes and skeletal muscle. During Ca2+ overload sparks serve as sites for the initiation and propagation of Ca2+ waves in myocytes. Computer simulations of spark-mediated waves are performed with model release sites that reproduce the adaptive Ca2+ release observed for the ryanodine receptor. The speed of these waves is proportional to the diffusion constant of Ca2+, D, rather than √D, as is true for reaction-diffusion equations in a continuous excitable medium. A simplified 'fire-diffuse-fire' model that mimics the properties of Ca2+-induced Ca2+ release (CICR) from isolated sites is used to explain this saltatory mode of wave propagation. Saltatory and continuous wave propagation can be differentiated by the temperature arid Ca2+ buffer dependence of wave speed. Fil:Ponce-Dawson, S. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina. JOUR info:eu-repo/semantics/openAccess http://creativecommons.org/licenses/by/2.5/ar http://hdl.handle.net/20.500.12110/paper_00063495_v75_n2_p595_Keizer |
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Universidad de Buenos Aires |
institution_str |
I-28 |
repository_str |
R-134 |
collection |
Biblioteca Digital - Facultad de Ciencias Exactas y Naturales (UBA) |
topic |
article calcium transport computer simulation diffusion coefficient fluorescence heart muscle cell nonhuman skeletal muscle transverse tubular system animal biological model cell membrane diffusion heart muscle kinetics metabolism skeletal muscle calcium ryanodine receptor Animals Calcium Cell Membrane Computer Simulation Diffusion Kinetics Models, Biological Muscle, Skeletal Myocardium Ryanodine Receptor Calcium Release Channel |
spellingShingle |
article calcium transport computer simulation diffusion coefficient fluorescence heart muscle cell nonhuman skeletal muscle transverse tubular system animal biological model cell membrane diffusion heart muscle kinetics metabolism skeletal muscle calcium ryanodine receptor Animals Calcium Cell Membrane Computer Simulation Diffusion Kinetics Models, Biological Muscle, Skeletal Myocardium Ryanodine Receptor Calcium Release Channel Keizer, J. Smith, G.D. Ponce-Dawson, S. Pearson, J.E. Saltatory propagation of Ca2+ waves by Ca2+ sparks |
topic_facet |
article calcium transport computer simulation diffusion coefficient fluorescence heart muscle cell nonhuman skeletal muscle transverse tubular system animal biological model cell membrane diffusion heart muscle kinetics metabolism skeletal muscle calcium ryanodine receptor Animals Calcium Cell Membrane Computer Simulation Diffusion Kinetics Models, Biological Muscle, Skeletal Myocardium Ryanodine Receptor Calcium Release Channel |
description |
Punctate releases of Ca2+, called Ca2+ sparks, originate at the regular array of t-tubules in cardiac myocytes and skeletal muscle. During Ca2+ overload sparks serve as sites for the initiation and propagation of Ca2+ waves in myocytes. Computer simulations of spark-mediated waves are performed with model release sites that reproduce the adaptive Ca2+ release observed for the ryanodine receptor. The speed of these waves is proportional to the diffusion constant of Ca2+, D, rather than √D, as is true for reaction-diffusion equations in a continuous excitable medium. A simplified 'fire-diffuse-fire' model that mimics the properties of Ca2+-induced Ca2+ release (CICR) from isolated sites is used to explain this saltatory mode of wave propagation. Saltatory and continuous wave propagation can be differentiated by the temperature arid Ca2+ buffer dependence of wave speed. |
format |
JOUR |
author |
Keizer, J. Smith, G.D. Ponce-Dawson, S. Pearson, J.E. |
author_facet |
Keizer, J. Smith, G.D. Ponce-Dawson, S. Pearson, J.E. |
author_sort |
Keizer, J. |
title |
Saltatory propagation of Ca2+ waves by Ca2+ sparks |
title_short |
Saltatory propagation of Ca2+ waves by Ca2+ sparks |
title_full |
Saltatory propagation of Ca2+ waves by Ca2+ sparks |
title_fullStr |
Saltatory propagation of Ca2+ waves by Ca2+ sparks |
title_full_unstemmed |
Saltatory propagation of Ca2+ waves by Ca2+ sparks |
title_sort |
saltatory propagation of ca2+ waves by ca2+ sparks |
url |
http://hdl.handle.net/20.500.12110/paper_00063495_v75_n2_p595_Keizer |
work_keys_str_mv |
AT keizerj saltatorypropagationofca2wavesbyca2sparks AT smithgd saltatorypropagationofca2wavesbyca2sparks AT poncedawsons saltatorypropagationofca2wavesbyca2sparks AT pearsonje saltatorypropagationofca2wavesbyca2sparks |
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1807322744035999744 |