去甲乌药碱对血液动力学的影响及耐受性与安全性

目的：探讨去甲乌药碱（HG）能否用作心脏负荷试验用药以及安全性与耐受性,并与多巴酚丁胺（DB）进行血液动力学作用比较,方法：选择6只杂种犬,分别量静脉输注HG和DB。HG的剂量每分钟为1、2、4μg/kg,而DB剂量每分钟为5、10、20μg/kg,每个剂量均输注5min,实验中检测心率（HR）、外周血压（BP）、心输出量（CO）、心脏耗氧量（MOC）、冠状动脉血流量（CBF）及心电图（ECG),用核素心室显像测左室射血分数（LVEF）的变化,另用8只犬作HG的耐受性及安全性实验,所采用HG剂量开始每分钟为1μg/kg,然后逐步增至每分钟500μg/kg。实验中记录动物的HR、BP及ECG变化。结果：HG及DB的给药过程中,HR、MOC、CO及CBF均随机药物输注剂量的增加而升高。HG输注过程中收缩压（SBP）变化不明显,在而舒张压（DBP）有轻度下降,HR的增加是出现早而且上升快。在整个血液动力学实验中,除个别犬偶发室性早搏外,未见ECG异常,实验中无动物死亡。结论：静脉输注HG可以使心脏产生明显的正力性和正时性效应,同时伴有轻度的DBP下降,没有其他严重副作用发生。

Effects of higeramine on hemodynamics and its tolerability and safety, an experimental study

OBJECTIVE: To investigate the effects of higeramine (HG) on hemodynamics and its tolerability and safety so as to see if it can be used in cardiac loading test, and to compare the hemodynamic effects of HG and dobutamine (DB). METHODS: Six dogs were infused intrevenously with HG in escalating doses from l microgram/kg/min through 2 microgram/kg/min and to 4 microgram/kg/min, each dose being given for 5 minutes. Then the dogs were infused intravenously with DB at the escalating doses from 5 microgram/kg/min through 10 microgram/kg/min to 20 microgram/kg/min, each dose being given for 5 minutes. Heart rate (HR), blood pressure (BP), cardiac output (CO), myocardial oxygen consumption (MOC), and coronary blood flow (CBF) were measured at the beginning of test and by the end of each dose-infusion. Electrocardiography was conducted in the meantime. Left ventricular ejection fraction (LVEF) was measured with radionuclide equilibrium ventriculography. Another 8 dogs were given HG at the escalating doses from 1 microgram/kg/min up to 500 microgram/kg/min, each dose being infused for 3 minutes, to observe the tolerability and safety of HG, HR, BP, and ECG were monitored during the test. RESULTS: Intravenous administration of HG results in significant inotropic and chronotropic effects on the heart. HR, MOC, CO and CBF all increased in a dose-dependent manner in both HG and DB tests. HG did not cause significant change in systolic blood pressure (SBP), but a slight decrease in diastolic blood pressure (DBP) was found. HR increased steeply to the peak, and then remained at a plateau level. No significant ECG abnormality was seen except a few occasional premature ventricular beats. No dog died during the study. CONCLUSION: HG can be used in pharmacological stress test with remarkable tolerability and safety even at the dosage of 500 microgram/kg/min without serious adverse effect. It can be used as an alternative agent to DB under appropriate circumstances.