The Effects Of Different Drugs On The Protein Expression And MRNA Transcription Of Natriuretic Peptide In The Rats With CHF

Objectives: To investigate the effects of the different drugs on protein expression and mRNA transcription of natriuretic peptide and the transcript factor GATA-4 mRNA in rat with congestive heart failure (CHF) .Then,to compare the difference among the three kinds of drugs.Methods:The congestive heart failure model was induced by ligating the left anterior descending arteries of Spreague-Dawley (SD) rats to form the myocardial infarction for 6 weeks. The rats were divided into five groups: sham-operated group, control group,imidapril-treated group,digoxin-treated group,amlodipine-treated group.The plasma atrial natriuretic polypeptide (ANP) were measured by the radioimmunoassay(RIA). The brain natriuretic peptide (BNP ) mRNA and GATA-4 mRNA transcription were detected by reverse transcription-polymerase chain raction (RT-PCR) in the border zone and remote area of the myocardial infarction at 3,7,28 days respectively.The BNP expression were analysed by immunohisochemistry in the border zone and remote area of the myocardial infarction at 3,7,28 days respectively. The t test, chi square test, Mann-Whitney test, multivariate factorial analysis, ordinal logistic regression of cumulative odds, Pearson test were used to satistic the data with the SSPS11.0 software package.The value of p<0.05 was considered significant.Results: In the Imidapril group, the plasma ANP level, myocardial BNP expressionand BNP mRNA transcription decreased significantly (p<0.01); transcript factor GATA-4 mRNA transcription was down-regulated simultaneously (p<0.01); the BNP mRNA andGATA-4 mRNA transcription was positive correlated significantly ( r=0.741, p<0.01 ) . In the Digoxin group,the plasma ANP, myocardial BNP expression and BNP mRNA transcription decreased significantly (p<0.01) ;GATA-4 mRNA transcription decreased too ( p<0.05 ) ; the BNP mRNA and GATA-4 mRNA transcription was positive correlated as well, but not close-knit ( r=0.263,p<0.05 ) .In the Amlodipine group, the plasma ANP, myocardial BNP expression, BNP mRNA transcription remain unchanged ( p>0.05 ) ; but the GATA-4 mRNA transcription was enhanced significantly ( p<0.05 ) ; the BNP mRNA and GATA-4 mRNA transcription was not correlated ( r= -0.167, p >0.05 ) . Theremore , to compare with the amlodipine group, the imidapril and digoxin reduced the plasma ANP level, myocardial BNP expression and BNP mRNA transcription markedly(p<0.01, p<0.05 respectively). On the other hand, the decrease of plasma ANP level, myocardial BNP expression, BNP mRNA and GATA-4 mRNA transcription in the Imidapril group was more significant than that in the Digoxin group ( p<0.05 ) .Conclusions: l.The different kinds of drugs have different Effects on the proteinexpression and mRNA transcription of natriuretic peptide. 2. Imidapril and Digoxin can reduce the plasma ANP, myocardial BNP expression and BNP mRNA transcription ;the action in Imidapril is stronger than in digoxin. The action of Imidapril maybe be related with the change of GATA-4 mRNA transcription .The effect of Digoxin is not related close with the mechanim of GATA-4 mRNA transcription . 3.Amlodipine can not influence the plasma ANP, myocardial BNP expression and BNP mRNA transcription markedly.