Belkina L M, Kolarova R N, Meerson F Z
Biull Eksp Biol Med. 1991 Nov;112(11):465-7.
The electrical threshold of ventricular fibrillation induced by premature single impulses and the ectopic activity and also an abnormal conduction during vagus inhibition of sinus node were estimated 24 hours after the administration of isoproterenol (10 mg/kg, s/c, on time) in rats. In addition the cardiac contractile function of the left ventricle was studied. The study was performed on male Wistar rats, 250-300 body weight, under nembutal anesthesia. Isoproterenol had no effect on the contractile function in the rest and during maximal isometric load, induced by coarctation of ascending aorta. But in the treated animals the threshold of fibrillation fell more than 2-fold and the vagal bradycardia was more 2-fold then in the untreated animals. The AB-block, idioventricular rhythm and extrasystoles appeared during vagal bradycardia in treated animals, while in the untreated ones there were no any disturbances. The preliminary administration of the antioxidant ionol (BMT, 30 mg/kg, per os, in sun oil) prevented the enumerated shifts.
在大鼠皮下按时注射异丙肾上腺素（10毫克/千克）24小时后，评估了单个早搏诱发心室颤动的电阈值、异位活动以及迷走神经抑制窦房结期间的异常传导。此外，还研究了左心室的心脏收缩功能。该研究在体重250 - 300克的雄性Wistar大鼠身上进行，戊巴比妥麻醉。异丙肾上腺素对静息状态下以及升主动脉缩窄诱导的最大等长负荷时的收缩功能无影响。但在接受治疗的动物中，颤动阈值下降超过两倍，迷走神经引起的心动过缓比未治疗的动物快两倍多。在接受治疗的动物迷走神经心动过缓期间出现了AB阻滞、心室自主节律和期前收缩，而未治疗的动物则没有任何干扰。预先给予抗氧化剂离子醇（BMT，30毫克/千克，口服，溶于葵花籽油）可防止上述变化。
