An, China). Ten rabbits served as controls (handle group). Heart failure
An, China). Ten rabbits served as controls (handle group). Heart failure was induced by doxorubicin within the remaining 40 rabbits employing previously described solutions (19,22). Briefly, doxorubicin hydrochloride (Zhejiang HiSun Minsheng Pharmaceutical Co., Ltd, Zhejiang, China) was diluted in regular saline at a concentration of 1 mgml then 1.0 mgkg body weight was injected by means of the ear vein twice weekly for eight consecutive weeks. Heart failure was diagnosed by echocardiography with a sector scanning ultrasound probe at eight MHz (GE Vivid VII color Doppler ultrasound, GE Medicals, Fairfield, CT, USA) at the end of eight weeks. On the 25 rabbits that developed heart failure, 13 (NAC group) received 300 mgkg NAC (Hangzhou Minsheng Pharmaceutical Co., Ltd, Hangzhou, Zhejiang, China) when everyday for 4 weeks. The remaining 12 rabbits with heart failure (HF group) received typical saline of an equal volume. All the animal experiments have been approved by the Animal Care and Use Committee of Medicine College of Wuhan University. Echocardiography evaluation. In all the 3 groups, echocardiography was performed in the end of week 12 with a sector scanning ultrasound probe at eight MHz (GE Vivid VII colour Doppler ultrasound). Prior to the echocardiography, the animals received an intramuscular injection of diazepam (two mg) for sedation. A parasternal extended axis view of the left ventricle was made use of to detect the inner diameter in the left atrium and left ventricle, left ventricular end-diastolic diameter (LVEDD), left ventricular end-systolic diameter (LVESD) and interventricular septal thickness (IVST). The brief axis view at the papillary muscle level was employed for M-shaped sampling to detect the ejection fraction (EF) and fraction shortening (FS). The parasternal four-chamber view was employed to observe the movement from the ventricular wall. The long-axis view from the pulmonary artery was employed to detect the inner diameter in the pulmonary artery and frequency spectrum. The apical three-chamber view, four-chamber view and five-chamber view have been employed to detect the frequency spectrum from the aorta and mitral valve.Hemodynamics analysis and collection of myocardial tissue. In the end in the study, the rabbits in all groups were intravenously anesthetized with 20 urethane at five mlkg. Following catheterization from the aorta, the heart price (HR), left ventricular systolic IDO custom synthesis stress (LVSP), left ventricular end-diastolic stress (LVEDP), peripheral mean arterial stress (MAP), as well as the maximal and minimal rates on the rise in left ventricular stress (dpdtmax and -dpdtmin, respectively) had been measured making use of the BL-420E Amebae Storage & Stability biological function detection system (Chengdu Taimeng Science and Technology Co., Ltd, Chengdu, China). The animals have been straight away sacrificed by injection of 5 ml of ten potassium chloride. Thoracotomy was performed and the heart was collected. The left ventricle was isolated and fixed in four paraformaldehyde or liquid nitrogen for further use. Analysis of myocardial cell apoptosis. The myocardium was fixed in four paraformaldehyde, embedded in paraffin and sectioned. Terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL) was performed making use of an In Situ Cell Death Detection kit (Roche, Mannheim, Germany) to detect the number of apoptotic cells in line with manufacturer’s directions. The normal cells have been identified as obtaining blue nuclei while the apoptotic cells had yellow-brown nuclei. 4 sections were randomly choose.