Platou E S, Myhre E S, Refsum H
Can J Physiol Pharmacol. 1986 Oct;64(10):1286-90. doi: 10.1139/y86-217.
Melperone has been found to possess vasodilating and slight positive inotropic properties in addition to its class III antiarrhythmic action. To determine whether some of these effects might be related to an alpha-adrenoceptor blocking action of melperone, phenoxybenzamine (10 mg/kg) was given as a 2-h infusion to 12 pentobarbital-anesthetized dogs. In addition, six of the dogs were given atenolol 0.5 mg/kg i.v. After a 1-h stabilizing period, melperone (0.5, 2.5, and 12.5 mg/kg) was given i.v. in cumulative doses to both series of dogs. In the presence of alpha-blockade as well as combined alpha- and beta-blockade, atrial, atrioventricular (AV) nodal, and ventricular refractoriness increased and heart rate and AV nodal conduction time decreased, as previously reported after addition of melperone alone. A slight increase in left ventricular (dP/dt)max occurred after the addition of melperone (2.5 mg/kg) in the presence of alpha- and beta-blockade, but only after the highest dose of melperone were small decreases in blood pressure and total peripheral resistance induced. The present study indicates that melperone combines the properties of class III antiarrhythmic action, slight positive inotropy, and alpha-adrenoceptor mediated vasodilation.
已发现美哌隆除具有Ⅲ类抗心律失常作用外，还具有血管舒张和轻微的正性肌力特性。为了确定这些作用中的某些是否可能与美哌隆的α-肾上腺素能受体阻断作用有关，对12只戊巴比妥麻醉的犬进行2小时静脉输注苯氧苄胺（10mg/kg）。此外，给其中6只犬静脉注射阿替洛尔0.5mg/kg。在1小时的稳定期后，对两组犬静脉注射累积剂量的美哌隆（0.5、2.5和12.5mg/kg）。如先前单独添加美哌隆后所报道的那样，在存在α-阻断以及联合α-和β-阻断的情况下，心房、房室（AV）结和心室的不应期延长，心率和房室结传导时间缩短。在存在α-和β-阻断的情况下，添加美哌隆（2.5mg/kg）后左心室（dP/dt）max略有增加，但仅在美哌隆最高剂量后血压和总外周阻力才出现小幅下降。本研究表明，美哌隆兼具Ⅲ类抗心律失常作用、轻微正性肌力作用以及α-肾上腺素能受体介导的血管舒张特性。
