Effects of α-methylnorepinephrine on cardiac function and myocardium at early stage of postresuscitation in rabbits / 中华急诊医学杂志

ABSTRACT

Objective To observe the effects of selective α2-adrenergic receptor agonist alpha-Methylnore-pinephrine(α-MNE) as a vasopressin agent on hemodynamics, troponin T(cTnT) and myocardium in the rabbit cardiopulmonary resuscitation. Method Eighteen health rabbits, weighing 2.5 - 3.5 kg, both male and female,were provided by Lanzhou institute of veterinary medicine. After setting up rabbit model of cardiopulmonary resuscitation, 18 rabbits were randomly divided into three groups. The rabbits in group A as a operation-control group were processed with anesthesia, endotracheal intubation, and surgery without ventricular fibrillation induced. The rabbits in group B as a epinephrine group were administered with 30 ug/kg epinephrineduring CPR. The rabbits in group C as a MNE group were administered with 100 ug/kg α-MNE during CPR. The left ventrictdar end-diastolic pressure(LVEDP), left ventricular pressure rise and fall rate(± dp/dt) and serum concentrations of BNP were measured. Statistic package of SPSS 10.0 was used for the data analysis and significant differences between means were evaluated by ANOVA analysis. Results Compared with group A, LVEDP of other two groups gradually increased respectively(P < 0. 01), and peak ± dp/dt decreased in other two groups(P<0.01). Increase in LVEDP in group C was less than that in group B(P<0.05), whereas peak ± dp/dt in group C were higher than that in group B(P<0.05), at the same stage. Compared with group A, the cTnT of the remaining two groups increased(P<0.01, respectively),and reached peak at 30 minutes. In group C, the elevation of cTnT was less than that in group B(P<0.05) during the same period. In group B and C, myocardial injury was seen under a light microscope, but the injury in group C was lighter than that in group B. Conclusion The methylnorepinephrine can lessen the myocardial dysfunction after CPR.