Effect of propofol on concentration of catecholamine in coronary outflow of isolated contracting rat heart after ischemiar-rperfusion injury / 中华麻醉学杂志

ABSTRACT

Objective The normothermic isolated contracting rat heart model was used to investigate the mechanism of protective effect of propofol on left ventricular function and myocardial metabolism against ischemia-reperfusion injury by determination of the catecholamme concentration in the coronary outflow. Methods forty healthy male SD rats weighing 310-450 g were randomly divided into 4 groups of each 10 animals control group, propofol 10?mol/L (P10), 50?mol/L (P50) and 100?mol/L (P100). The animal were sacrificed by knock-out and the heart was immediately removed. The aorta was connected to a Larigendorff apparatus and retrogradely perfused with oxygenated (95% O, and 5% CO2) Krebs-Henseleit buffer (KHB) for 5 min. Then the left ventricle was perfused through a cannula inserted in pulmonary vein at a constant pressure of 12.5 cm H2O (preload). The pressure at aorta outflow was 90 cm H2O (afterload). Different concentrations of propofol in KHB were prepared. Global ischemia of the heart was induced by suspension of perfusion for 25 min followed by 30 min reperfusion. Coronary flow (CF), aortic flow (AF), cardiac output (CO = AF + CF), HR, left ventricular peak systolic pressure (LVPSP), left ventricular end-diastolic pressure (LVEDP), left ventricular developed pressure (LVDP = LVPSP-LVEDP) and the product of LVDP and HR were measured and recorded 5 min and immediately before ischemia and 5, 10, 15, 20, 25 and 30 min following reperfusion. Coronary outflow was collected for determination of creatine kinase (CK) and catecholamine ( epinephrine, norepinephrine and dopamine) concentrations.Results Before ischemia CF was significantly higher and CO, HR, LVPSP and LVDP ? HR were significantly lower in the 3 propofol groups in comparison with the controls. During reperfusion CF, CO, HR, LVPSP and LVEDP recovered much better in the propofol groups than those in control group. In group P50 LVDP ? HR reached 88.7% of the pre-ischemic value while in control group only 56.3% . The CK and catecholamine concentrations were not significantly different among the 4 groups before ischemia. During reperfusion CK, epinephrine and noeepinepherine concentrations were significantly lower in propofol groups than in control group (P