| Objective: Acute myocardial infarction(AMI) often accompanied with ventricular remodeling.Ventricular remodeling includes the changes of cardiac myocytes and extracellular matrix(ECM).The extracellular matrix degradation plays the pivotal role in the process of ventricular remodeling.Matrix metalloproteinases(MMPs) are a zine-dependent proteolytic enzymes family,which are responsible for extracellular matrix degradation.Moreover it can be activated after AMI.In present experiment,we investigated the change of matrix metalloproteinase 2 (MMP-2) in rats with myocardial infarction(MI) and the effect of Lotensin and Captopril on MMP-2 expression and ventricular remodeling.Methods:AMI model in rats was established by the ligation of left anterior descending coronary.Wistar rats were randomized to AMI control group(no therapy,n=14),Lotensin group(100mg/kg/d,n=14)and Captopril group(100mg/kg/d , n=14).The rats without operation were put into the sham-operated group.10 weeks after operation, haemodynamics parameters which included left ventricular systolic pressure(LVSP),left ventricular end-diastolic pressure (LVEDP),left ventricular pressure maximal rate of rise and fall(dP/dTmax and dP/dTmin) were measured. The expression of MMP-2 in blood serum was quantified with ELISA.The hearts were dislodged after executing the rats.Left ventricular weigh index(LVWI) and left ventricular long axis(LVLA) were measured.They were used to represent the degree of left ventricular hypertrophy and distension.Histopathologic slide was made,and collagen density was measured in non-infarcted area.Result: Compared with sham-operated group rats, LVEDP,MMP-2,LVWI,LVLA and collagen density of all operated groups were significantly increased(P<0.05).LVSP,dP/dTmax and dP/dTmin were significantly reduced (P<0.05). Compared with control group,LVEDP,MMP-2,LVWI,LVLA and collagen density of Lotensin group and Captopril group were significantly reduced (P<0.05).LVSP , dP/dTmax and dP/dTmin were significantly increased (P<0.05). Compared with Lotensin group,LVEDP,LVSP,dP/dTmax,dP/dTmin ,MMP-2,LVWI,LVLA and collagen density of Captopril group had no statistics difference (P>0.05).Conclusion:1.Left ventricular remodeling occurred at 10 weeks after AMI in rats,which can be improved by the treatment of Lotensin and Captopril.2.10 weeks after AMI in rats,the expression of MMP-2 in blood serum upregulate,and Lotensin and Captopril can inhibit its upregulation. 3. 10 weeks after AMI in rats,there was no significant difference at inhibiting the expression of MMP-2 and ventricular remodeling between Lotensin and Captopril.
|
PDF Full Text Request