Kalyoncu N I, Ozyavuz R
Department of Pharmacology, Karadeniz Technical University Medical School, Trabzon, Turkey.
Fundam Clin Pharmacol. 1999;13(6):646-9. doi: 10.1111/j.1472-8206.1999.tb00375.x.
Digoxin inhibits the membrane-bound ATPase enzyme, resulting in a rise in intracellular sodium and activated outward potassium current, predisposing to arrhythmias. In this study, the effect of ketanserin, thought to block outward potassium currents, was investigated on digoxin-induced arrhythmias. Twenty-four guinea-pigs were studied in four groups (control, ketanserin 0.5 mg/kg, ketanserin 1 mg kg, ketanserin 2 mg/kg). Under pentobarbital anaesthesia (40 mg/kg), 15 min after injection of saline or ketanserin, digoxin (0.6 mg/kg) was administered through the jugular vein. Carotid artery blood pressure and electrocardiogram (ECG) were recorded. The time for the onset of the first arrhythmia and incidence of ventricular tachycardia (VT), ventricular fibrillation (VF), and premature ventricular contraction (PVC) were determined. Arrhythmias were scored according to the MacLeod scale. Ketanserin produced minor haemodynamic effects and lacked, by itself, arrhythmogenic effects at the doses studied. However, it increased the time for the onset of the first digoxin-induced arrhythmia and decreased the incidence of VT, VF and PVC. We conclude that ketanserin inhibits digoxin-induced arrhythmias in guinea-pigs.
地高辛抑制膜结合型ATP酶，导致细胞内钠离子浓度升高，并激活外向钾电流，从而易引发心律失常。在本研究中，对被认为可阻断外向钾电流的酮色林针对地高辛诱发的心律失常的作用进行了研究。24只豚鼠被分为四组（对照组、酮色林0.5毫克/千克组、酮色林1毫克/千克组、酮色林2毫克/千克组）进行研究。在戊巴比妥麻醉（40毫克/千克）下，注射生理盐水或酮色林15分钟后，通过颈静脉给予地高辛（0.6毫克/千克）。记录颈动脉血压和心电图（ECG）。确定首次出现心律失常的时间以及室性心动过速（VT）、心室颤动（VF）和室性早搏（PVC）的发生率。心律失常根据麦克劳德量表进行评分。酮色林产生轻微的血流动力学效应，在所研究的剂量下其本身无致心律失常作用。然而，它延长了首次地高辛诱发的心律失常的发作时间，并降低了VT、VF和PVC的发生率。我们得出结论，酮色林可抑制豚鼠地高辛诱发的心律失常。
