| Literature DB >> 17310075 |
Hikaru Tanaka1, Hideaki Shimada, Iyuki Namekata, Toru Kawanishi, Naoko Iida-Tanaka, Koki Shigenobu.
Abstract
Involvement of the Na+/Ca2+ exchanger in ouabain-induced inotropy and arrhythmogenesis was examined with a specific inhibitor, SEA0400. In right ventricular papillary muscle isolated from guinea-pig ventricle, 1 microM SEA0400, which specifically inhibits the Na+/Ca2+ exchanger by 80%, reduced the ouabain (1 microM)-induced positive inotropy by 40%, but had no effect on the inotropy induced by 100 microM isobutyl methylxantine. SEA0400 significantly inhibited the contracture induced by low Na+ solution. In HEK293 cells expressing the Na+/Ca2+ exchanger, 1 microM ouabain induced an increase in intracellular Ca2+, which was inhibited by SEA0400. The arrhythmic contractions induced by 3 microM ouabain were significantly reduced by SEA0400. These results provide pharmacological evidence that the Na+/Ca2+ exchanger is involved in ouabain-induced inotropy and arrhythmogenesis.Entities:
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Year: 2007 PMID： 17310075 DOI： 10.1254/jphs.fp0060911
Source DB: PubMed Journal: J Pharmacol Sci ISSN： 1347-8613 Impact factor: 3.337