title: Elementary calcium release events from the sarcoplasmic reticulum in the heart.
abstract: Ca(2+) release events underlie global Ca(2+) signaling yet they are regulated by local, subcellular signaling features. Here we review the latest developments of different elementary Ca(2+) release features that include Ca(2+) sparks, Ca(2+) blinks (the corresponding depletion of Ca(2+) in the sarcoplasmic reticulum (SR) during a spark) and the recently identified small Ca(2+) release events called quarky SR Ca(2+) release (QCR). QCR events arise from the opening of only a few type 2 ryanodine receptors (RyR2s) - possibly only one. Recent reports suggest that QCR events can be commingled with Ca(2+) sparks and may thus explain some variations observed in Ca(2+) sparks. The Ca(2+) spark termination mechanism and the number of RyR2 channels activated during a Ca(2+) spark will be discussed with respect to both Ca(2+) sparks and QCR events.
authors.affiliation: Center for Biomedical Engineering and Technology, Department of Physiology, University of Maryland School of Medicine, University of Maryland, 725 W. Lombard Street, Baltimore, MD 21201, USA. dbrochet@umaryland.edu
authors.forename: Didier X P
authors.initials: DX
authors.lastname: Brochet
authors.forename: Dongmei
authors.initials: D
authors.lastname: Yang
authors.forename: Heping
authors.initials: H
authors.lastname: Cheng
authors.forename: W Jonathan
authors.initials: WJ
authors.lastname: Lederer
mesh_terms: D000818:Animals; D002118:Calcium / Q000378:metabolism*; D006801:Humans; D009206:Myocardium / Q000378:metabolism*; D019837:Ryanodine Receptor Calcium Release Channel / Q000502:physiology; D012519:Sarcoplasmic Reticulum / Q000378:metabolism*
chemical_list: D019837:Ryanodine Receptor Calcium Release Channel; D002118:Calcium