title: Regulatory volume decrease in cardiomyocytes is modulated by calcium influx and reactive oxygen species.
abstract: We investigated the role of Ca(2+) in generating reactive oxygen species (ROS) induced by hyposmotic stress (Hypo) and its relationship to regulatory volume decrease (RVD) in cardiomyocytes. Hypo-induced increases in cytoplasmic and mitochondrial Ca(2+). Nifedipine (Nife) inhibited both Hypo-induced Ca(2+) and ROS increases. Overexpression of catalase (CAT) induced RVD and a decrease in Hypo-induced blebs. Nife prevented CAT-dependent RVD activation. These results show a dual role of Hypo-induced Ca(2+) influx in the control of cardiomyocyte viability. Hypo-induced an intracellular Ca(2+) increase which activated RVD and inhibited necrotic blebbing thus favoring cell survival, while simultaneously increasing ROS generation, which in turn inhibited RVD and induced necrosis.
authors.affiliation: Centro FONDAP Estudios Moleculares de la Célula, Departamentos de, Santiago 838-0492, Chile.
authors.forename: Diego
authors.initials: D
authors.lastname: Rojas-Rivera
authors.forename: Jessica
authors.initials: J
authors.lastname: Díaz-Elizondo
authors.forename: Valentina
authors.initials: V
authors.lastname: Parra
authors.forename: Daniela
authors.initials: D
authors.lastname: Salas
authors.forename: Ariel
authors.initials: A
authors.lastname: Contreras
authors.forename: Barbra
authors.initials: B
authors.lastname: Toro
authors.forename: Mario
authors.initials: M
authors.lastname: Chiong
authors.forename: Claudio
authors.initials: C
authors.lastname: Olea-Azar
authors.forename: Sergio
authors.initials: S
authors.lastname: Lavandero
mesh_terms: D000818:Animals; D001692:Biological Transport; D002118:Calcium / Q000378:metabolism* / Q000494:pharmacology; D002374:Catalase / Q000378:metabolism; D048429:Cell Size / Q000187:drug effects; D002470:Cell Survival / Q000187:drug effects; D002478:Cells, Cultured; D003593:Cytoplasm / Q000187:drug effects / Q000378:metabolism; D015971:Gene Expression Regulation, Enzymologic; D032383:Myocytes, Cardiac / Q000166:cytology* / Q000187:drug effects / Q000378:metabolism; D009336:Necrosis / Q000378:metabolism; D009997:Osmotic Pressure / Q000187:drug effects; D051381:Rats; D017207:Rats, Sprague-Dawley; D017382:Reactive Oxygen Species / Q000378:metabolism*
chemical_list: D017382:Reactive Oxygen Species; D002374:Catalase; D002118:Calcium