莲心碱对正常大鼠血压和左室收缩功能的影响

目的 了解莲心碱对正常大鼠的降压作用与左室收缩功能的关系。方法 分别经大鼠静脉注射2mg/kg和6mg/kg的莲心碱,左心室插管,同步记录左心室压力和微分,测算心肌收缩因子最大缩短速度(V_(Max))等参数。结果 2mg/kg和6mg/kg莲心碱可不同程度的降低大鼠收缩压(SAP)、舒张压(DAP)、左室压力(LVP)上升最大速率(dp/dt_(Max))和V_(Max),对心率和左室开始收缩到开始射血的时间(t-dp/dt_(Max))则无明显影响。莲心碱降低V_(Max)的有效作用时间与SAP基本一致,莲心碱降低DAP的有效作用时间长于LVP、dp/dt_(Max)和V_(Max) 结论 经心碱具有明显的降低血压作用,莲心碱降低DAP的作用大于SAP,莲心碱降低血压的主要作用部位在外周血管。莲心碱可降低正常大鼠左室收缩功能,这一效应可能参与莲心碱的早期降压作用。

Effects of liensinine on blood pressure and left ventricular contractile function in normal rats

Objective To evaluate effects of liensinine on blood pressure (BP) and left ventricular contractile function in normal rats. Methods Two doses of liensinine (2mg/kg and 6mg/kg) were intravenously injected in two groups of rats. Catheters were put into left ventricles (LV) in rats,blood pressure, left ventricular pressure (LVP) and differentiation (dp/ dt) were recorded, maximum rate of LV systolic pressure (dp/dtMax) and the maximum velocity of shortening of the contractile element (VMaX) and other hymodynamic parmeters were meassured. Results intravenous liensinine in the doses of 2mg/ kg and 6mg/kg had different effects in de- creasing systolic pressure (SAP),diastolic pressure (DAP),dp/dtMax and VMax in rats. Effective time of liensinine in decreasing VMax is consistent with that of SAP, effective time of liensinine in decreasing DAP is longer than those of LVP, dp/dtMax and VMax,and liensinine is more effective in decreasing DAP than SAP. Conclusion Liensinine (2mg/kg and 6mg/kg) can significantly decrease BP. This effect is mainly occurred in peripheral vessels. Liensinine (2mg/kg and 6mg/kg) can decline the function of left ventricular contraction in normal rats, which is associated with the decrease of SAP.