title: Ruthenium red reduces the Ca2+ sensitivity of Ca2+ uptake into cardiac sarcoplasmic reticulum.
abstract: Ruthenium red inhibits mitochondrial Ca2+ uptake and is widely used as an inhibitor of ryanodine-sensitive Ca2+ channels that function to release Ca2+ from the sarcoplasmic reticulum (SR) of muscle cells. It also has effects on other Ca2+ channels and ion transporters. To study the effects of ruthenium red on Ca2+ transport into the SR of cardiac muscle cells, fluorescence measurements of Ca2+ uptake into cardiac SR vesicles were made. Ruthenium red significantly decreased the Ca2+ sensitivity of SR uptake in a dose-dependent manner at concentrations ranging from 5 microM to 20 microM. There were no significant effects of ruthenium red on the maximum velocity or the Hill coefficient of SR Ca2+ uptake.
authors.affiliation: Department of Physiology and Biophysics, University of Calgary, 3330 Hospital Drive NW, Calgary, Alberta, Canada T2N 4N1.
authors.forename: G J
authors.initials: GJ
authors.lastname: Kargacin
authors.forename: Z
authors.initials: Z
authors.lastname: Ali
authors.forename: M E
authors.initials: ME
authors.lastname: Kargacin
mesh_terms: D000818:Animals; D001692:Biological Transport / Q000187:drug effects; D002118:Calcium / Q000378:metabolism*; D004285:Dogs; D066298:In Vitro Techniques; D009206:Myocardium / Q000378:metabolism*; D012430:Ruthenium Red / Q000494:pharmacology*; D012519:Sarcoplasmic Reticulum / Q000187:drug effects* / Q000378:metabolism / Q000648:ultrastructure; D013050:Spectrometry, Fluorescence
chemical_list: D012430:Ruthenium Red; D002118:Calcium