绞股蓝总黄酮对麻醉犬心脏血流动力学及冠脉血流量的作用

Effects of total flavones of Gynostemma pentaphyllum(Thunk) Mak on coronary blood flow and cardiac hemodynamics in anesthetized dogs

研究绞股蓝总黄酮对麻醉开胸犬血流动力学及冠脉血流量的作用，探讨其对心脏功能的药理作用．将实验犬25只，随机分为生理盐水阴性对照组、地尔硫卓阳性药对照组和绞股蓝总黄酮大、中、小剂量组．经戊巴比妥钠30mg·kg^-1静脉麻醉后开胸，分别测定动脉血压、心率、冠脉血流量、左室内压、左室内压最大上升与下降速率（±dp／dtmax）、动脉血氧含量，计算心肌耗氧量、心脏左室做功、冠脉阻力、心输出量等．结果显示，动物十二指肠给TFG60min后，动脉血压、心率、左室内压、＋dp／dtmax和心肌耗氧量明显降低，冠脉血流量明显上升，与生理盐水阴性对照组比较均有显著性差异（P〈（0．05～0．01））．实验表明，绞股蓝总黄酮可扩张冠脉血管、增加冠脉流量、降低心率和心脏后负荷，心肌耗氧量下降，从而改善心肌的供血供氧，调整心脏血管的顺应性，对心血管系统起到调整和改善作用．

The effects of total flavones of gynostemma pentaphyllum （thunk） Mak （TFG） on coronary blood flow （CBF） and cardiac hemodynamics was studied and the pharmacological action of TFG on cardiac function in anesthetic dogs was investigated. A total of 25 dogs anesthetized with pentebarbital sodium （30 mg · kg^-1, iv. ） were randomly grouped into the normal saline control group, diltiazem （Dil） group,low-dose TFG,middling-dose TFG and high-dose TFG group. Arterial pressure （AP） of the femoral artery, heart beat （HB）, the coronary Blood flow of left ventricle （CBF）, left ventricular systolic pressure （LVSP）, left maximum ascending rate and descending rate （± dp/dtmax ） of LVSP, oxygen contents of the artery were detected, respectively. Myocardial oxygen consumption （MVO2）, left vnetricular work（LVW）, coronary artery resistance （CAR） and cardiac output（CO） were calculated according to the correlative formula. After duodenum given TFG 60 min, AP, HB, LVSP ＋dp/dtmax ang MVO2 lowered significantly （P〈 0.05-0.01）, CBF increased considerably. Significant difference was found in comparison with normal saline control groups. The results showed that TFG can dilate the coronary artery, increase CBF, decrease the MVO2 and has a reduction of the cardiac afterload so that it can improve the oxygen supply of the myocardium, and give a favorable regulation of the compliance of the cardiac vessels. As a result, the cardiovascular performance was ameliorated.