RESUMO
AIM:To investigate the effects of irbesartan on the expression of hepatocyte growth factor (HGF) at mRNA and protein levels in rats with myocardial infarction (MI), and to explore the mechanisms of irbesartan attenuating myocardial fibrosis.METHODS:The male Wistar rat model of MI was successfully established.The surviving rats 24 h after the operation were randomly divided into 3 groups:model group,irbesartan group and sham group, with 9 rats in each group.The rats in irbesartan group were treated with the solution of irbesartan (50 mg·kg-1·d-1) by intragastric administration, while the rats in model group and sham group received the equal volume of saline by the same way.The body weight and left ventricle mass (LVM) of the rats were measured at the 4th week after operation, and the pathological changes of the ischemic myocardium were observed with HE staining.Meanwhile, the expression of HGF at mRNA and protein levels was detected by RT-qPCR and Western blot.RESULTS:HE staining showed that the myocardial cells in sham group were in neat arrangement, while the cardiac structure in model group and irbesartan group was in disorder.The pathological changes in irbesartan group were less than that in model group.No difference in the body weight at the 4th week after operation was observed, while the LVM was significantly different among the 3 groups (P<0.01).The LVM in model group was higher than that in sham group (P<0.01), and that in irbesartan group was higher than that in sham group (P<0.05).The LVM in irbesartan group was lower than that in model group (P<0.05).The expression of HGF at mRNA and protein levels was detected in each group.The expression of HGF at mRNA and protein levels in irbesartan group was higher than that in sham group (P<0.05), and that in model group was higher than that in sham group (P<0.01).Moreover, the mRNA and protein levels of HGF in irbesartan group were lower than those in model group (P<0.05).CONCLUSION:The LVM of MI rats with the treatment of irbesartan was reduced obviously at the 4th week after operation, and the pathological changes were also improved.At the 4th week after the operation, the treatment of irbesartan inhibited the expression of HGF at mRNA and protein levels.
RESUMO
Objective To investigate the effects of astragalosides(AST)on angiogenesis of myocardium in rats after myocardial infarction.Methods Myocardial infarction(MI)was induced by ligation of the proximal left anterior descending coronary artery,30 postoperative rats were randomly divided into three same-size groups,i.e,medical group A(AST 2.5 mg · kg-1 · d-1),medical group B(AST 10mg · kg-1 · d-1)and control group(physiological saline).All of three groups were treated with intraperitoneal injection of 2ml dose for 4 weeks.The pathological changes of the heart tissue were observed by H-E staining and the micro-vascular count(MVC)/micro-vascular density (MVD)were calculated by CD34-staining.Results HE staining showed cardiac fabric disarrangement,granulation tissue generation,and fibroblast proliferation;The change of medical groups was less obvious than the control group; the change of group B with higher dose was less obvious than group A.CD34 staining showed that regeneration of neovascularization at the margin of myocaardium infarction was seen in all of three groups;for the MVC/MVD,medical groups were significantly higher than the control group,while group B is significantly higher than group A (all P ＜0.01).Conclusion AST can improve myocardial ischemia of rats after myocardial infarction.AST can promote angiogenesis in ischemic myocardium of rats,and the effect is positively correlated with AST dose.