title: Doxapram hydrochloride aggravates adrenaline-induced arrhythmias accompanied by bidirectional ventricular tachycardia.
abstract: Objectives. Doxapram hydrochloride is a respiratory stimulant that has an inhibitory effect on myocardial IK1 potassium channels and is thought to increase membrane instability and excitability in myocardial cells. We examined the arrhythmogenic effects of doxapram hydrochloride in a rat model of halothane adrenaline-induced arrhythmia. Methods. Thirteen female Wistar rats (12-14 weeks old) were used in the study. Animals were anesthetized with inhalation of halothane to permit observation of the effects of doxapram hydrochloride on halothane adrenaline-induced arrhythmia. Time-dependent changes in ECG repolarization characteristics (QT, QTc, JTp, JT, and Tp-e intervals) were studied. Results. Doxapram hydrochloride itself did not induce arrhythmia but did induce bidirectional ventricular tachycardia after addition of adrenaline. Conclusion. Drug-induced impairment of intracellular Ca(2+) regulation caused BVT in the absence of genetic abnormalities in proteins in the sarcoplasmic reticulum.
authors: Division of Clinical Pathophysiology, Graduate School of Health Sciences, Fujita Health University, 1-98 Dengakugakubo Kutsukake, Toyoake, Japan.
authors: Shota
authors: S
authors: Oikawa
authors: Division of Pharmacology, Graduate School of Health Sciences, Fujita Health University, Japan.
authors: Hiroko
authors: H
authors: Nomura
authors: Division of Clinical Pathophysiology, Graduate School of Health Sciences, Fujita Health University, 1-98 Dengakugakubo Kutsukake, Toyoake, Japan.
authors: Miki
authors: M
authors: Nishio
authors: Division of Clinical Pathophysiology, Graduate School of Health Sciences, Fujita Health University, 1-98 Dengakugakubo Kutsukake, Toyoake, Japan.
authors: Rina
authors: R
authors: Nagata
authors: Division of Clinical Pathophysiology, Graduate School of Health Sciences, Fujita Health University, 1-98 Dengakugakubo Kutsukake, Toyoake, Japan.
authors: Tadayoshi
authors: T
authors: Hata