Chiba S, Kobayashi M, Furukawa Y
Eur J Pharmacol. 1979 Jul 15;57(1):13-9. doi: 10.1016/0014-2999(79)90098-0.
The isolated blood-perfused preparations of canine atrium were suspended in a bath and perfused with arterial blood led from the carotid artery of the heparinized donor dog. Disopyramide caused dose-related negative chronotropic and inotropic effects in a dose range of 30-1000 microgram when injected directly into the cannulated sinus node artery of the isolated atrium. The order of potencies for inducing the negative chronotropic effect in isolated atrium preparations was verapamil greater than propranolol greater than lidocaine = quinidine greater than phenytoin greater than or equal to disopyramide greater than procainamide. On the other hand, the order of potencies for inducing the negative inotropic effect was verapamil = propranolol greater than lidocaine greater than or equal to phenytoin greater than disopyramide greater than procainamide greater than or equal to quinidine. When disopyramide (1 mg/kg or 3 mg/kg) was administered i.v. into the jugular vein of the donor dog, the systemic blood pressure of the donor dog was markedly decreased. However, the tension developed and sinus rate of the isolated atrium were only slightly decreased. Disopyramide produced greater suppression at higher frequencies and slightly depressed the calcium chloride-induced positive inotropic effects.
将犬心房的离体血液灌注标本悬挂于浴槽中，并用来自肝素化供体犬颈动脉的动脉血进行灌注。当直接注入离体心房插管的窦房结动脉时，丙吡胺在30 - 1000微克的剂量范围内产生剂量相关的负性变时和变力作用。在离体心房标本中诱导负性变时作用的效能顺序为：维拉帕米＞普萘洛尔＞利多卡因 = 奎尼丁＞苯妥英＞或等于丙吡胺＞普鲁卡因胺。另一方面，诱导负性变力作用的效能顺序为：维拉帕米 = 普萘洛尔＞利多卡因＞或等于苯妥英＞丙吡胺＞普鲁卡因胺＞或等于奎尼丁。当将丙吡胺（1毫克/千克或3毫克/千克）静脉注射到供体犬的颈静脉时，供体犬的全身血压明显降低。然而，离体心房产生的张力和窦性心率仅略有降低。丙吡胺在较高频率时产生更大的抑制作用，并轻微抑制氯化钙诱导的正性变力作用。
