title: Effects of contrast media on calcium transients and motion in cultured ventricular cells.
abstract: To investigate the mechanisms of the negative inotropic effects of contrast media, we superfused spontaneously contracting cultured chick embryo ventricular cells with Renografin-76 and iohexol (12% solutions), and hypertonic sucrose during simultaneous measurement of [Ca2+]i transients (indo-1) and motion (video-motion detector system). Exposure to contrast agents caused a significant reduction of contractility, with Renografin-76 having a much greater effect on amplitude of motion than iohexol. Renografin-76 significantly depressed [Ca2+]i transient amplitude, whereas iohexol had no effect. Addition of Ca2+ to correct for calcium binding by Renografin-76 completely reversed its depression of [Ca2+]i transients but only partially reversed the negative inotropic effects. Hypertonic sucrose caused a significant decrease in contraction amplitude, with no significant effects on [Ca2+]i transient amplitude. We conclude that the marked negative inotropic effect of Renografin-76 is caused by both calcium binding and hypertonicity. The less marked depression of contractility produced by iohexol likely is a result of hypertonicity and not caused by alteration of [Ca2+]i.
authors.affiliation: Department of Medicine, University of Utah School of Medicine, Salt Lake City 84132.
authors.forename: D A
authors.initials: DA
authors.lastname: Bell
authors.forename: G A
authors.initials: GA
authors.lastname: Peeters
authors.forename: W L
authors.initials: WL
authors.lastname: Davis
authors.forename: O
authors.initials: O
authors.lastname: Kohmoto
authors.forename: J A
authors.initials: JA
authors.lastname: Nelson
authors.forename: W H
authors.initials: WH
authors.lastname: Barry
mesh_terms: D000818:Animals; D002118:Calcium / Q000378:metabolism*; D015220:Calcium Channels / Q000187:drug effects / Q000378:metabolism; D002478:Cells, Cultured; D002642:Chick Embryo; D003287:Contrast Media / Q000494:pharmacology*; D003973:Diatrizoate / Q000494:pharmacology; D003974:Diatrizoate Meglumine / Q000494:pharmacology; D004338:Drug Combinations / Q000494:pharmacology; D006352:Heart Ventricles / Q000187:drug effects / Q000378:metabolism / Q000503:physiopathology; D007472:Iohexol / Q000494:pharmacology; D009200:Myocardial Contraction / Q000187:drug effects*; D009994:Osmolar Concentration; D013395:Sucrose / Q000378:metabolism
chemical_list: D015220:Calcium Channels; D003287:Contrast Media; D004338:Drug Combinations; D003973:Diatrizoate; D003974:Diatrizoate Meglumine; D007472:Iohexol; D013395:Sucrose; C027278:urovision; D002118:Calcium