EMD_(56431)对麻醉犬血流动力学的作用

Effects of EMD_(56431) on Hemodynamics in Anaesthetized Dogs

采用静脉注射和灌胃的方式给予犬 EMD56 431 ,在麻醉开胸状态下 ,分别在颈内动脉、股动脉、主动脉或冠状动脉左旋支及左心室插管或放置各种型号的探头 ,同步检测心输出量 (CO) ,冠脉流量 (CF) ,脑血流量 (CBF)和股动脉血流量 (FF) ,左室收缩压 (L VSP) ,左室压上升和下降速率 (± dp/ dtmax) ,左室舒末压 (L VEDP) ,收缩压(SAP) ,舒张压 (DAP) ,平均动脉压 (MAP) ,心电图 (ECG)等指标 ,并计算出心率 (HR) ,心脏指数 (CI)和外周阻力 (TPR)。结果 :经静脉注射 EMD56 431 2 5 ,5 0 ,10 0 μg/ kg均可对麻醉犬产生剂量依赖性的降压作用 ,同时减慢 HR,增加 CF,降低 TPR和± dp/ dtmax,除静脉注射 10 0μg/ kg EMD56 431 外 ,其余对心功能 ,器官血流量 ,ECG无明显影响 ;灌胃给予 EMD56 431 2 0 0 μg/ kg也具有明显而持久的降压作用 ,降压时未见反射性 HR加快。静注和灌胃 EMD56 431 产生的效应相当。结果提示 :EMD56 431 对麻醉犬有明显而持久的降压作用 ,且该药生物利用度较高 。

EMD 56431 was intravascularly (i.v.) injected or irrigated intragastrically (i.g.) to study the effects of EMD 56431 on hemodynamics in anaesthetized dogs. Cardiac output (CO), coronary flow (CF), cerebral blood flow (CBF), femoral flow (FF), and the left ventricular derivative developed force ( dp/dt max ), systolic pressure (LVSP), left ventricular end diastolic pressure (LVEDP), systolic blood pressure (SAP), diastolic blood pressure (DAP), mean arterial pressure (MAP) and electrocardiogram (ECG) were measured by cannulation in internal carotid artery, femoral artery, aortic artery, or coronary artery and all kinds of sensors. Heart rate (HR), cardiac index (CI) and peripheral resistance (TPR) were calculated. The resluts showed that the administation of EMD 56431 (25, 50, 100 μg/kg, i.v.) produced hypotensive effects on the anaesthetized dogs in a dose dependent manner. Simultaneously, HR and ±dp/dt max were decreased, and CF increased. Expect the dose of EMD 65431 100 μg/kg, no statistically significant changes were noted in the heart pump function and organ blood flow in the rest. The administration of EMD 56431 (200 μg/kg, i.g.) also significantly reduced the blood pressure permanently, but no reflexible increased HR were found. The potency of EMD 56431 by the ways of i.v. and i.g. was comparable. It is demonstrated that EMD 56431 can markedly and continuously decrease the blood pressure in the anaesthetized dogs, and has high bioavailability.