Spontaneous calcium waves without contraction in cardiac myocytes.
Spontaneous Ca2+ waves were visualized in quiescent cardiomyocytes loaded with the Ca(2+)-sensitive fluorescent probe, Fluo-3, and imaged by laser confocal microscopy. No sarcomere shortening was detected during wave propagation. This type of Ca2+ waves began at the periphery or in a central region of a myocyte and propagated the length of the cell in one or two directions. The average velocity of wave propagation was 32 microns/sec and the estimated concentration of Ca2+ oscillated from 124, at the bottom, to 311 nM, at the pick of the wave. Ca2+ waves were not confined to a single cell but could spread from cell to cell. These results describe a type of spontaneous Ca2+ waves which does not induce a contractile response in cardiomyocytes.
López
J R
JR
Department of Internal Medicine, Mayo Clinic, Mayo Foundation, Rochester, MN 55905, USA.
Jovanovic
A
A
Terzic
A
A
D000814:Aniline Compounds; D000818:Animals; D002118:Calcium / Q000378:metabolism*; D002478:Cells, Cultured; D005456:Fluorescent Dyes; D006168:Guinea Pigs; D006321:Heart / Q000502:physiology; D006352:Heart Ventricles / Q000166:cytology; D007700:Kinetics; D018613:Microscopy, Confocal; D009200:Myocardial Contraction; D009206:Myocardium / Q000378:metabolism*; D012518:Sarcomeres / Q000502:physiology* / Q000648:ultrastructure; D013997:Time Factors; D014966:Xanthenes
D000814:Aniline Compounds; D005456:Fluorescent Dyes; D014966:Xanthenes; C059715:Fluo-3; D002118:Calcium