当前位置： SCI文献检索 > JOURNAL OF PHARMACOLOGICAL AND TOXICOLOGICAL METHODS期刊下所有文献 > Comparison of the QT interval response during sinus and paced rhythm in conscious and anesthetized beagle dogs.

Comparison of the QT interval response during sinus and paced rhythm in conscious and anesthetized beagle dogs.

Abstract：

INTRODUCTION:The aim of the present study was to compare sensitivity in detecting the drug-induced QT interval prolongation in three dog models: conscious telemetered at sinus rhythm and conscious and anesthetized dogs during atrial pacing. The test substances used represent different chemical classes with different pharmacological and pharmacokinetic profiles. METHOD:Dofetilide and moxifloxacin were tested in all models, whereas cisapride and terfenadine were tested in the conscious telemetered and paced models. All substances were given as two consecutive 1.5-h intravenous infusions (infusions 1 and 2). The individual concentration-time courses of dofetilide, moxifloxacin, and cisapride were linked to the drug-induced effects on the QT interval and described with a pharmacokinetic-pharmacodynamic model to obtain an estimate of the unbound plasma concentrations at steady state that give a 10- and 20-ms drug-induced QT interval prolongation (CE10ms and CE20ms). RESULTS:In the conscious telemetered, conscious paced, and anesthetized dog models, the mean CE10ms values were 1.4, 4.0, and 2.5 nM for dofetilide and 1300, 1800, and 12,200 nM for moxifloxacin. For cisapride, the CE10ms values were 8.0 and 4.4 nM in the conscious telemetered and conscious paced dog models. The drug-induced QT interval prolongation during the last 30 min of infusions 1 and 2 was comparable in the conscious models, but smaller in the anesthetized dog model. Terfenadine displayed a marked delay in onset of response, which could only be detected by the extended ECG recording. DISCUSSION:All dog models investigated detected QT interval prolongation after administration of the investigated test substances with similar sensitivity, except for a lower sensitivity in the anesthetized dogs following moxifloxacin administration. The conscious telemetered dog model was favorable, mainly due to the extended continuous ECG recording, which facilitated detection and quantification of delayed temporal differences between systemic exposure and drug-induced QT interval prolongation.

journal_name

J Pharmacol Toxicol Methods

journal_title

Journal of pharmacological and toxicological methods

authors

Ollerstam A,Visser SA,Duker G,Forsberg T,Persson AH,Nilsson LB,Björkman JA,Gabrielsson J,Al-Saffar A

doi

10.1016/j.vascn.2007.05.002

subject

Has Abstract

pub_date

2007-09-01 00:00:00

pages

131-44

issue

eissn

1056-8719

issn

1873-488X

pii

S1056-8719(07)00201-8

journal_volume

pub_type

杂志文章

在线工具

Comparison of the QT interval response during sinus and paced rhythm in conscious and anesthetized beagle dogs.