title: Excess noise in modified conductance states following the interaction of ryanoids with cardiac ryanodine receptor channels.
abstract: The interaction of ryanodine with the ryanodine receptor (RyR) produces profound changes in channel function. Open probability increases dramatically and conductance is reduced. In this report we describe differences in the properties of reduced conductance states produced by the interaction of ryanodine derivatives with RyR channels. Some reduced conductance states are considerably noisier than the normal open state of the RyR channel. Inspection and analysis of these events reveals that the excess noise arises from transitions between two conductance states. Following the interaction of certain ryanodine derivatives, RyR channels undergo transitions between two conformations with slightly different ion-handling properties.
authors.affiliation: Cardiac Medicine, National Heart and Lung Institute, Imperial College of Science, Technology and Medicine, Dovehouse Street, SW3 6LY, London, UK. t.bhavna@ic.ac.uk
authors.forename: Bhavna
authors.initials: B
authors.lastname: Tanna
authors.forename: William
authors.initials: W
authors.lastname: Welch
authors.forename: Luc
authors.initials: L
authors.lastname: Ruest
authors.forename: John L
authors.initials: JL
authors.lastname: Sutko
authors.forename: Alan J
authors.initials: AJ
authors.lastname: Williams
mesh_terms: D000818:Animals; D004553:Electric Conductivity; D066298:In Vitro Techniques; D008081:Liposomes; D008564:Membrane Potentials / Q000187:drug effects; D009206:Myocardium / Q000378:metabolism*; D011487:Protein Conformation / Q000187:drug effects; D012433:Ryanodine / Q000031:analogs & derivatives* / Q000378:metabolism / Q000494:pharmacology; D019837:Ryanodine Receptor Calcium Release Channel / Q000737:chemistry / Q000187:drug effects / Q000378:metabolism*; D012519:Sarcoplasmic Reticulum / Q000378:metabolism; D012756:Sheep
chemical_list: C113821:21-amino-9-hydroxyryanodine; D008081:Liposomes; D019837:Ryanodine Receptor Calcium Release Channel; D012433:Ryanodine