Effects And Mechanism Of Simvastatin On Angiotensin Ⅱ Induced Myocardial Hypertrophy Of Neonatal Rats

ObjectiveTo abserve the protective effects and mechanism of simvastatin onAngiotensin Ⅱ induced myocardial hypertrophy of neonatal rats.MethodsUsing cultured myocardial cells as a model, we observe the effects ofsimvastatin （0.1μmol/L） by Angiotensin Ⅱ （10-7mol/L） induced myocardialhypertrophy of neonatal rats. Myocardial cells by newborn rats were randomlydivided into six groups:the Angiotensin Ⅱ group （Ang Ⅱgroup）, the controlgroup, the simvastatin and Angiotensin Ⅱ group（Sim and AngⅡ group）, theCyclosporine A （5μg/mL）and Angiotensin Ⅱ group（CsA and AngⅡ group）, onlysimvastatin group（Sim group）, only Cyclosporine A group（CsA group）. Duringthe groups, the pretreatment of60minutes with simvastatin in Sim group, thepretreatment of60minutes with Cyclosporine A in CsA group, The rest of thetwo groups are to deal with a balanced salt solution. Then Angiotensin Ⅱwasadded into Ang Ⅱ group, Sim+Ang Ⅱ groupand CsA+Ang Ⅱ group; thebalanced salt solution was joined in the rest three groups respectively, Allgroups continue to be cultured another48hours. The cardiomyocytes size wassurveyed through the computer image analysis system. The total proteincontent was measured by the method of coomassie blue staining.[Ca²⁺]itransient was surveyed through Till image system using Fura2/AM as fluresence. The expression of calcineurin（CaN） were measured by Westernbolt.Results（1）Compared to the control group, in Ang Ⅱ group,the total protein ofmyocardial cells, the volume of myocardial cardiomyocytes,[Ca²⁺]itransientwere rised significantly （p<0.01） and expression of calcineurin（CaN） was risedsignificantly; in Sim and AngⅡ group, CsA and AngⅡ group, Sim group andCsA group, the total protein of myocardial cells, the volume of myocardialcardiomyocytes,[Ca²⁺]itransient and expression of calcineurin were notstatistical significance;（2）Compared with Ang Ⅱ group, in Sim and AngⅡ group,CsA and AngⅡ group, Sim group and CsA group, the total protein of myocardialcells,the volume of myocardial cardiomyocytes,[Ca²⁺]itransient were reduced（p<0.05）and expression of calcineurin（CaN） was also reduced（p<0.05）;（3）Compared with CsA and AngⅡ group, the total protein content, thecardiomyocytes volume,[Ca²⁺]itransient and expression of calcineurin have arising trend in Sim and AngⅡ group, but there is not statistically significant.ConclusionThese results suggest that simvastatin could defend myocardial cells fromAngiotensinⅡ-induced cardiomyocyte hypertrophy.The effects of simvastatinmay be related to Ca²⁺/calcineurin sigal pathway.