Evaluation Of Nitroglycerin Delay Protection Effect On Myocardial Stuning Using MCE And IBS

IntroductionIdentification and protection of viable myocardium after acute myocardial infarction or in the setting of severe chronic ischemic heart disease has important clinical implications.Evaluation of Nitroglycerin Delay Protection Effect onMyocardial Stuning Microvascular Function and the Role of PKCUsing Myocardial Contrast EchocardiographyTwenty - one anaesthetized dogs were randomly divided into three groups: ischemia and reperfusion ( group A) and nitroglycerin (group B) , nitroglycerin plus chelerythrine chloride group ( group C).In group A, the anterior descending coronary artery was blocked for 20 minutes ,subsequently,and reperfused for 120 minutes, Then MCE was performed during reperfusion in 0,30 ,60,90,120 min.In group B nitroglycerin was given with the speed of 2μg/( kg . min) intravenously, after 24 h by followed the same step as the group A.In group C chelerythrine chloride was given intravenously within 5 min , then nitroglycerin was given with the speed of 2μg/( kg . min) intravenously, after 24 h by followed the same step as the group A. During ischemia and reperfusion the parameters of time - intensity curve were measured in corresponding regional myocardium using AD technique before and after ACH injection. PI ratio (PIR) and AUC ratio (AUCR) of pre - to post - ACH were calculated at eachof the corresponding examining times. Gross pathologic specimen was stained with Evans blue (EB) and triphenyl tetrazolium chloride (TTC) after test.Evaluation of Nitroglycerin Delay Protection Effect onMyocardial Stuning contraction FunctionUsing Integrated BackscatterFourteen anaesthetized dogs were randomly divided into two groups:ischemia and reperfusion ( group A) and nitroglycerin (group B) .In group A, the anterior descending coronary artery was blocked for 20 minutes, and reperfused for 120 minutes.In group B nitroglycerin was given with the speed of 2u,g/( kg. min) intravenously, after 24 h by followed the same step as the group A . During ischemia and reperfusion and after Dob was injected with 10u,g/( kg. min) at reperfusion 30, Variations of magnitude of cyclic variation of integrated backscatter ( CVIB) , Average image intensity ( All) , Standardized All, and regional wall trucking (WT) were measured via HP 5500 color Doppler imaging system, The correlations between CVIB and WT were analyzed .Gross pathologic specimen was stained with Evans blue( EB) and triphenyl tetrazolium chloride (TTC) after test.Result1. At baseline PI and AUC in three groupas increased considerable via aortic root injection of ACH.The peak intensity! PI ) i area under the curve( AUC ) and endothelium - dependent relaxation (EDR) in myocardial stuning were significantly decreased versus in the normal myocardium (P <0.05) .which was increased gradually with the prolonging reperfusion duration,in addition , which...