Study On Effect And Mechanism Of Bushenfuyuan Prescription On Hypertrophic Cadiocyte Due To Abdominalaorta Stenosis In Rats

OBJECTIVE The model rats with myocardial hypertrophy were due to abdominal aorta stenosis. We cured the rats with captopril and BuShenFuYuan Prescription of different dose, to observe Left Ventricular Mass Index; pathologic changes of left ventricular myocardium; concentrations of angiotensinⅡ(AngⅡ) in plasma and cardiac tissue of left ventricular; the expression of left ventricular myocardial angiotensinⅡtype 1 (AT1) receptor mRNA and its receptor protein, to approach the effect and mechanism of BuShenFuYuan Prescription on the hypertrophic cadiocyte due to abdominalaorta stenosis in rats.METHODS Models of rats with myocardial hypertrophy were induced by abdominal aortic constriction.60 male SD rats were randomly allocated to sham group, model group, captopril group, BSFY Prescription high dosage group(BSFY1) and BSFY Prescription low dosage group (BSFY2); Left Ventricular Mass Indexes were observed; pathologic changes of left ventricular myocardium were viewed with HE staining method; left ventricular myocytes ultramicrostructure were observed by electron microscope; concentration of AngⅡin plasma and cardiac tissue of left ventricular were measured by Radioimmunoassay; RT-PCR was used to detect the expression of left ventricular myocardial AT1 receptor mRNA; the changes of myocardial AT1 eceptor protein were observed by immunohistochemistry. The experimental data were analysis with the profession software of SPSS 11.5. Quantitative data were expressed as mean values±standard deviation (x±s). The data to compare the experimental group and control group were analyzed using one-factor analysis of variance, values of P≤0.05 were regarded as statistically significant.RESULTS1. LVMI The changes of LVMI in model group were increased comparing with the sham group(P<0.01); while the BSFY1 and BSFY2 were significantly different from those in model group (P<0.01), similar to captopril group.2. Pathologic changes of left ventricular myocardium HE staining Under light microscope, HE staining of cardiac muscle in sham group:the size and form were normal, the fibers lined up in order, while there were great different in model group:the diameter of cardiac cells were increased; the fibers of interstitial tissue were in a great mess. HE staining of BSFY1 and BSFY2 were same to those of captopril group. 3. Left ventricular myocytes ultramicrostructure The left ventricular myocytes ultramicrostructure of sham group were eumorphism:the morphous of cellular nucleus, cell-substance, chondrosome, sarcoplasmic reticulum, muscle fibril were normal; while there were great different in model group:the chondrosome appear to degeneration, such as crista mitochondriales decreased, fracture; the density of stroma became thinner; sarcoplasmic reticulum was expanding; myofibrillar degeneration such as:the myofibril broke, confused, the brink of cell nucleus irregularity; chromatin moved to verge. The left ventricular myocytes ultramicrostructure of captopril group, BSFY1 and BSFY2 were same to that of sham group.4. The level of plasma Ang II The level of plasma Ang II in model group was higher than that of sham operation group (P<0.01). The plasma AngⅡlevels those in captopril group, BSFY1 and BSFY2 were lower than model group significantly(P<0.01).5. The Ang II level of cardiac tissue of left ventricular The AngⅡlevel of cardiac tissue of left ventricular in model group was higher than that of sham operation group (P<0.01). The cardiac tissue of left ventricular Ang II levels those in captopril group, BSFYi and BSFY2 were lower than model group (P<0.01).6. The AT1R mRNA expression of cardiac tissue of left ventricular The AT1R mRNA expression of cardiac tissue of left ventricular in model group was higher than that of sham operation group (P<0.01). The AT1R mRNA expressions of cardiac tissue of left ventricular those of captopril group, BSFY1 and BSFY2 were lower than that of model group significantly (P<0.01).7. The myocardial AT1 receptor protein The myocardial AT1 receptor protein in model group was higher than that in sham operation group (P<0.01). The myocardial AT1 receptor proteins those of captopril group, BSFY1 and BSFY2 were lower than that in model group (P< 0.01).CONCLUSION(1) The result shows:eight weeks later, the LVMI of rats with abdominal aorta stenosis were significantly increased. We copied succeed model rats with myocardial hypertrophy, and confirmed further that pressure-overload is an important etiological factor for myocardial hypertrophy.(2) The concentrations of Ang II in plasma in rats with pressure-overload were increased; the AngⅡlevels of cardiac tissue, the expressions of left ventricular myocardial angiotensinⅡtype 1 receptor mRNA and its receptor proteins were significantly upregulation also, which meant that the nerve-endocrine-cytokine system was activated, and caused the left ventricular hypertrophy in rats with pressure overload.(3) BSFY Prescription can reduce the AngⅡlevel of plasma and cardiac tissue of left ventricular, decrease the expression of left ventricular myocardial AngiotensinⅡtype 1 receptor mRNA and its receptor protein significantly, restrain the activation of nerve-endocrine-cytokine system, relief the left ventricular hypertrophy in rats with pressure overload that similar to captopril.(4) Chinese herb Prescription with effect of invigorating-kidney and tonifying-heart, blood-activating and water-disinhibiting can reverse left ventricular hypertrophy on rats with abdominal aorta stenosis, which maybe concerned with the decreasing AngⅡlevel of plasma and cardiac tissue of left ventricular and depressing the transcription and translation of AT1 receptor gene.