PubMed:10666509 JSONTXT

{"project":"PubmedHPO","denotations":[{"id":"T1","span":{"begin":251,"end":263},"obj":"HP_0001662"},{"id":"T2","span":{"begin":496,"end":507},"obj":"HP_0011675"},{"id":"T3","span":{"begin":541,"end":551},"obj":"HP_0011675"},{"id":"T4","span":{"begin":675,"end":686},"obj":"HP_0011675"},{"id":"T5","span":{"begin":770,"end":794},"obj":"HP_0001663"},{"id":"T6","span":{"begin":1244,"end":1255},"obj":"HP_0011675"},{"id":"T7","span":{"begin":1287,"end":1298},"obj":"HP_0011675"},{"id":"T8","span":{"begin":1372,"end":1384},"obj":"HP_0001662"},{"id":"T9","span":{"begin":1534,"end":1557},"obj":"HP_0004308"},{"id":"T10","span":{"begin":1546,"end":1557},"obj":"HP_0011675"}],"text":"Effects of zatebradine and propranolol on canine ischemia and reperfusion-induced arrhythmias.\n1,3,4,5-Tetrahydro-7,8-dimethoxy-3[3-[[2-(3, 4-dimethoxyphenyl)-ethyl]methylamino]propyl]-2H-3-benzazepin-2-one -hy drochloride (Zatebradine) is a specific bradycardiac agent, blocking the hyperpolarization-activated pacemaker current (I(f)), and thus has no negative inotropic effect. The purpose of this study was to examine whether zatebradine is effective against ischemia and reperfusion-induced arrhythmias in dogs compared to propranolol. Arrhythmia was induced by ligation of the left anterior descending coronary artery followed by reperfusion. Ischemia-induced biphasic arrhythmias were suppressed in both zatebradine and propranolol groups. During ischemia, fatal ventricular fibrillation occurred in four dogs in the control group, 0 in the zatebradine group, and two dogs in the propranolol group. Of the 31 dogs subjected to reperfusion, mortality rates in the zatebradine, propranolol, and control groups were 56%, 75%, and 86%, respectively, and there were no significant differences. In the heart beating 10 beats/min faster than the predrug heart rate by atrial pacing, both zatebradine and propranolol attenuated ischemia-induced arrhythmias but did not affect reperfusion arrhythmias. Our results suggest that I(f) and/or beta-adrenoceptors rather than the bradycardiac action might be related to the antiarrhythmic effects during ischemia, but that they do not play a role in the generation of the reperfusion-induced ventricular arrhythmias."}