【摘要】 <正> 3,4-二羟基苯乙酮(DHAP)是禿毛冬青叶中有效成分。临床用于冠心病患者,对心绞痛及部分患者的心律失常有一定缓解作用。整体动物实验表明,DHAP能扩张全身动脉,降低心脏后负荷,增加冠脉血流量。此作用可能为DHAP临床效应的作用机理之一。DHAP对心肌细胞直接作用的研究很少。范世藩报道DHAP 0.5～1mg/ml(相当于3.5～更多还原

【Abstract】 The effects of DHAP on electrical and mechanical activities were investigated by synchronously recording action potential and isometric tension in isolated myocardium. No influence was demonstrated on action potential (APA, APD₂₀、APD₉₀) by DHAP 10^-5～10^-3M in guinea pig palillary muscle. The inhibition on the force of contraction with the same concentration of DHAP, however, was shown in a concentration-dependent way. The effects of DHAP on the electrical and mechanical activities in cat papillary muscle were similar to those in guinea pig papillary muscle. With the dose of DHAP 10^-5～5×10^-4M, alteration of action potential of pacemaker cells was not observed in the isolated sinus node preparation of the rabbit. When the dosage was increased to 10^-3 M, the electrical activities were inhibited. The experimental results indicate that the effects of a certain dose of DHAP on inhibiting the tension in myocardium are available in clinical application. A warning is given that an increase in dosage may enhance the inhibition on contractile force in myocardium and inhibit the automaticity of sinus node pacemaker cells.更多还原