黄芪苷 Ⅳ对正常和心功能受抑制大鼠左心室心肌力学的影响

目的：研究黄芪苷Ⅳ对正常和心功能受抑制大鼠左心室心肌力学的效应，方法：采用左心室导管法，测定左心室压力（LVP）及其微分（dp/dt)，对iv黄芪苷IV（1mg/kg)对左心室心肌力学的效应，iv普萘洛尔（0．75mg/kg)，抑制大鼠心功能，观察黄芪苷IV的对抗作用，结果：黄芪苷IV使心率（HR）略有减慢，使左室压力上升最大速度（dp/dtmax)明显提高，具有性肌力作用。使左室压力下降的时间常数（T）显著缩短，改善心脏舒张功能，左心室射血的张力－时间指数（TTI＿无明显改变。表明该药在增强心肌收缩力的同时并未增加心肌耗氧量，对普萘洛尔抑制心功能的大鼠，用黄芪苷IV后dp/dtmax无显著降低，即该药可对普萘洛尔抑制心肌收缩力的作用。T值显著缩短，表明心脏舒张功能也有改善，心肌耗氧量不增加，结论：黄芪苷IV可改善心脏收缩及舒张功能，可望成为一种强心和改善心功能的药物。

Effects of astragaloside

To study the effects of astragaloside Ⅳ, which was obtained from Astragalus membranaceus Bge., on myocardiac dynamics and cardiac function on normal and cardiac depressant rat. Methods　Left ventricular pressure (LVP) and differential value of dp/dt were recorded by left ventricular catherization to observe the effect of 1 mg/kg iv astragaloside Ⅳ on normal and cardiac depressant rat induced by iv 0.75 mg/kg of Propanolol. Results　Astragaloside Ⅳ decreased heart rate slightly, and showed inotropic activity by increasing dp/dtmax significantly, with improvement of cardiac diastolic function. It shortened the time constant (T) and caused no obvious change on the tension time index (TTI) in normal rat. These results suggested that astragaloside Ⅳ did not increase cardiac oxygen consumption while exerting its inotropic effect. Conclusion　Astragaloside Ⅳ can improve both cardiac systolic and diastolic functions, and may be used as a candidate for the treatment of cardiac disfunction.