Abstract:ObjectiveTo observe the effects of anesthetics and other different kinds of reagents on ECG in mice .Methods Healthy ICR mice were randomly divided into 5 groups and respectively received intraperitioneal injection of one of the following anesthetics: pentobarbital sodium solution(PS)of 0.4% or 0.6%,10%ethyl carbamate(EC), 3% chloral hydrate(CH),2.5% tribromoethanol(TBE). Anesthetic effects were observed and compared between groups. Anesthetic inhibition effect on heart rate were compared between groups, or with those before administrating and of simultaneous normal saline(NS) group. Under the situation of CHinduced anesthesia, the effects of three kinds of adrenoreceptor agonists(adrenaline,noradrenaline and isoprenaline) on heart rate were observed and compared with that both of simultaneous NS group and before administrating. The drugs and reagents with the effects of inhibition to cardiomyocytes, including βadrenegic antagonist propranolol, sodium channel blocker lidocaine, lactic acid and potassium chloride were used to test their effects on ECG in mice.Results Three anesthetics of 0.6% PS, 3% CH and 2.5% TBE exhibit their satisfactory anesthetic effect, especially for 3% CH and 2.5% TBE ,which got a further more steady effect. Compared with those before administrating, the three anaesthetics mentioned above could significantly slow the heart rate(P<0.05) . These phenomenon could not be altered even though adrenoreceptor agonists were given intraperitoneously. Besides, it was found that both adrenaline and noradrenaline could significantly suppress heart rate, while resecptively compared with the situation before administrating(P<0.05 or <0.01) . The heart rates after administrating in certain concentration of propranolol, lidocaine, lactic acid and potassium chloride were slower than those before administrating(P<0.05 or <0.01) and, at the same time, the administration could also lead to various kinds of arrhymias. ConclusionAnesthetics could significantly inhibit cardic electrophysiological activity in mice and disturb the pharmacological effects of cardiovascular active medicines. ECG observations on conscious mice were of great importance not only for cardic electrophysiological, pharmacological and toxicological researches but also for preclinical and clinical medicine experimental teaching