Experimental Study On The Effects Of L-carnitine Early Treatment On Left Ventricular Remodeling, Cardiac Function After Acute Myocardial Infarction In SD Rats And It's Mechanism

PART 1 Establishment of acute myocardial infarction configuration in SD ratsObjective:This study sought to investigate the whole process of Establishment of acute myocardial infarction configuration in SD rats which comprise the choices of animals, the uses of breathing machine, the localization of the left anterior descending branch correctly, the operation of physiological recorder and the judgment of AMI model.Methods: AMI were conducted by ligating left anterior descending branch in male SD rats. Rats were randomly assigned to one of the following groups:AMI control(n=12), Sham operated rats(n=10) were selected randomly as non-infarction control. Then electrocardiogram(ECG),hemodynamics studies and echocardiography examination were performed,and the hearts of the rats were taken out and fixed with 10% formalin and pathologic analysis was performed. Results: Compared with the sham operated group, a significant decrease could be seen in ejection fraction(EF, 49.94±5.85%) and fractional shortening (FS, 21.78±3.15%) (all P<0.01),and a significant increase could be seen in left ventricular end-diastolic volume(LVEDV, 0.82±0.26ml)and left ventricular end-systolic pressure(LVESV, 0.38±0.15ml) among AMI groups. A significant increase could be seen in left ventricular end-diastolic pressure (LVEDP, 10.78mmHg±6.81mmHg),a significant decrease could be seen in left ventricular pressure maximal rate of rise and fall (±dp/dt, +3886.67±672.95mmHg/s, -3613.99±485.83mmHg/s), left ventricular systolic pressure(LVSP , 76.41±10.06mmHg) aortic systolic blood pressure( ASBP, 72.21±6.81mmHg), aortic diastolic blood pressure(ADBP, 51.84±6.24mmHg) and mean aortic pressure(MAP, 60.65±5.54mmHg),no difference in heart rate(HR, P>0.05) among AMI groups. A significant increase could be seen in heart weight, heart...