国产卡维地洛对麻醉犬血流动力学的影响

HEMODYNAMIC EFFECTS OF DOMESTIC CARVEDILOL IN ANESTHETIC DOGS

目的：观察国产卡维地洛（Ｃａｒ）对麻醉犬血流动力学的影响，了解该药对心血管系统的作用。方法：杂种家犬８只，戊巴比妥钠麻醉下记录心电、平均动脉压（ＭＡＰ）、左心室内压（ＬＶＰ）、心输出量（ＣＯ），观察静注Ｃａｒ０．１，０．３及１．０ｍｇ／ｋｇ后血流动力学各指标的变化。结果：静注Ｃａｒ后可引起麻醉犬ＭＡＰ，心率（ＨＲ），ＬＶＰ及其最大变化速率、左心室做功（ＬＶＷ）及总外周血管阻力明显下降，给药后１ｍｉｎ起效，药后１～５ｍｉｎ达最大效能，且具有剂量依赖性，１ｍｇ／ｋｇ剂量组药效可持续至给药后４５ｍｉｎ；Ｃａｒ对麻醉犬ＣＯ及左心室舒张末压无明显影响。结论：Ｃａｒ具有较广泛的心血管效应，除通过扩张外周阻力血管降低血压外，尚具有降低ＨＲ和抑制心肌收缩性能的作用，表明国产Ｃａｒ兼具α肾上腺素受体和β肾上腺素受体拮抗剂特性，支持该药为具有Ｓ（－）和Ｒ（＋）构型的外消旋化合物。

OBJECTIVE:Through observation on the hemodynamic action of domestic carvedilol to investigate its cardiovascular effects.METHODS:Domestic carvedilol was given to 8 anesthetic dogs by intravenous injection in a dose of 0.1,0.3 and 1.0 mg/kg and their mean arterial BP(MAP),left ventricular pressure(LVP),cardiac output(CO),and ECG were recorded and analyzed by computer.RESULTS:The MAP,HR,LVP,LVP±dp/dt max ,left ventricular work(LVW)and total peripheral resistance(TPR)of the anesthetic animals were significantly decreased by carvedilol injection with immediate onset of action and dosage dependent.For a dose of 1.0 mg/kg,these effects can be observed at 1 minute after drug given and maximum effects were observed at 1～5 minutes and lasted for 45 minutes.CONCLUSION:A broad cardiovascular effects were observed,beside a decrease in MAP induced by TPR reduction,decrease in HR and inhibition in contraction ability of heart can also be achieved.These results indicated that carvedilol is a recemic mixture with both β blockers’and α blockers’properties.