Taurine is an amino acid found in high concentration (20-30 mM) in mammalian heart. Treatment of rats with the transport antagonist guanidinoethyl sulfonate (GES) depletes cardiac taurine ($>$70%). Electrocardiograms were recorded weekly in restrained unanaesthetized rats. GES treatment caused a selective prolongation of the QT interval which was correlated with the degree of myocardial taurine depletion (r$ sp2$ = 0.92, p $<$ 0.001). Ventricular muscle action potential durations (APD$ sb{95}$) from taurine-depleted hearts were significantly prolonged compared to control (88 +/- 8 ms vs. 66 +/- 9 ms; p $<$ 0.001). Taurine supplements given to depleted rats reversed the taurine depletion and the QT prolongation; no effect was seen in controls. No action potential differences between control and "reversed" rats were seen. Superfusion of GES or taurine at concentrations of 0.2-10 mM had no effect on action potential characteristics of control or taurine-depleted hearts. When hamsters were GES-treated no cardiac biochemical or QT changes were seen.
| Identifer | oai:union.ndltd.org:LACETR/oai:collectionscanada.gc.ca:QMM.59626 |
| Date | January 1989 |
| Creators | De Roode, Michael R. |
| Publisher | McGill University |
| Source Sets | Library and Archives Canada ETDs Repository / Centre d'archives des thèses électroniques de Bibliothèque et Archives Canada |
| Language | English |
| Detected Language | English |
| Type | Electronic Thesis or Dissertation |
| Format | application/pdf |
| Coverage | Master of Science (Department of Physiology.) |
| Rights | All items in eScholarship@McGill are protected by copyright with all rights reserved unless otherwise indicated. |
| Relation | alephsysno: 001126946, proquestno: AAIMM66357, Theses scanned by UMI/ProQuest. |
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