Inhibition And Mechanism Of Astragaloside Ⅳ On Cardiac Hypertrophy In Pressure-overload Rat Heart Model

ObjectiveThrough observe astragaloside IV （As IV）for rat myocardial hypertrophyinhibition effect, discusses the effect and the relationship between myocardialenergy metabolism.MethodsaortiWith the aortic abdominal constriction(AAC) method to establish ratsmyocardial hypertrophy model. With60SD rats were randomly divided into4groups, each group of15only.They were sham operation, AAC postoperative,AAC+As IV（1mg·kg-1·d-1）and AAC+As IV（5mg·kg-1·d-1）12weeks group.Intraperitoneal injection of rats, after one week began to medicine until death.Examination indexes including electrocardiogram,hemodynamic parameters,HMI,LVMI, HE dyeing, Massion dyeing and cell diameter. Determine collagenprotein content of myocardial tissue and lactic acid(LA),free fatty acid (FFA) byuv spectrophotometry. Determine atrial natriuretic peptide(ANP) mRNAexpressions by PT-PCR.Difference observation to MMP change andmicrotubules restructuring by the Laser confocal microscope.ResultsAfter12weeks of rats AAC,rats myocardial hypertrophy, Left ventricularsystolic blood pressure and end-diastolic pressure were elevated,±dp/dtmax are increased; myocardial cell diameter were increased, arranging disorderly,collagen protein content and ANP mRNA increased, cytoskeleton happenedreconstruction. LA, FFA content increased obviously of myocardial tissue andMMP value lower. In As IV1mg rats, cardiac hemodynamic improve butmyocardial hypertrophy no change. Although LA, FFA of myocardial tissuereduced but have differences compared with Sham group. As IV5mg of ratsleft ventricular systolic blood pressure and+dp/dtmax rised significantly,Indexes were lower than that of the AAC and no difference with sham group.Effect of As IV on content of ATP and ADP and AMP in left ventricular tissueby high performance liquid chromatography(HPLC).ConclusionsThe effect of As IV has significant increase to myocardial contraction, Lowdoses can change hemodynamic parameters however high doses can inhibitmyocardial hypertrophy. The mechanism may improve cardiac energymetabolism, reduces accumulation in the mitochondria of LA and FFA,andmaintain MMP.