Experimental Study On Immature Myocardial Protective Effect Of Astragalus Injected Under Cardiopulmonary Bypass In Junior Dogs

Objective: To investigate protective effect of astragalus injectionpreconditioning on immature myocardium under cardiopulmonary bypass injunior dog.Methods: Twenty junior dogs with the same species, weight, healthand age were randomly divided into two groups,the reference group and theexperimental group.The experimental group offer astragalus injection(10mg/kg/d) one week in preoperative,the reference group offerphysiological saline (10mg/kg/d) one week in preoperative,routine establishof cardiopulmonary bypass model,and during open heart surgery,the bloodsample were taken in different time (blocking the aortic immediately, openthe aorta immediate and60min and120min),and detected the changes ofsuper oxide dismutase (SOD), creatine kinase isoenzyme (CK-MB),troponin I (cTnI) level，and the corresponding point in time to take a myocardial tissue0.5cm3, fixed in stationary liquid, routine paraffinembedded and sliced, SP immunohistochemistry methods were useddetection Bcl-2, Bax protein expression.Results:In the experimental group and the reference group blood serumCK-MB and cTnI were increased, but the experimental group increasedcompared with the reference group to be low.Both In the two groups,theactivity of SOD were decreased, but in the experimental group, the activityof SOD were significantly increased compared with the reference group.Inmyocardial tissue immunohistochemistry,the Bcl-2protein express inexperimental group was enhanced than that in reference group, and the Baxprotein express opposition result.Conclusions: Astragalus injection preconditioning may improve themicrocirculation,give oxygen to the organization during CPB and reduceCa2+overload in myocardial cell;Moreover Astragalus injection can enhancethe Bcl-2protein expression. These can reduce myocardial cell injury andapoptosis, may can offer preferable myocardial protection process.