To Investigate The Impact And Mechanism On The Myocardial Remodeling Of Yi-Xin Tai On Rabbit With Chronic Heart Failure From Ca²⁺-CaN-NFAT₃Signal Pathway

Objective To investigate the impact and mechanism on the myocardial remodeling of Yi-Xin tai on rabbit with chronic heart failure from Ca2+-CaN-NFAT3signal pathway.Methods Established the rabbit model of chronic heart model with adriamycin,and divided the successful model of rabbit into five groups: model group, high^middle and low dose of Yi-Xin tai groups and Losartan Potassium group, plus the normal control group,6groups in all.Every morning rabbit were given drug according to body surface area method,the conversion of crude drugs are as follows:the low、middle and high dose of Yi-Xin tai group was respectively given2.1g/(kg·d、4.2g/(kg·d) and8.4g/(kg·d), Losartan Potassium group was given2.75g/(kg·d), besides, the model group and normal group were given equally volume of physiological saline.Every rabbit was given only once a day for4weeksAfter the experiment we observed the serum concentration of brain natriuretic peptide,echocardiographic index, index of myocardial remodeling and the changes of myocardial tissue pathological structure and the myocardial ultrastructure, mearsured the concentration of myocardial intracellular calcium ion, the activity of CaN in myocardial tissue, protein expression of NFAT3and phosphorylated NFAT3in myocardial tissue、protein expression of GATA4and C-Myc.Results After4weeks,(1)compared with the model group, the serum levels of BNP of the treatment groups were significantly lower (P<0.01); compared with the low dose group, the levels of BNP of the middle、high dose groups of Yi-Xin tai and Losartan Potassium group were significantly lower(P<0.01);(2) compared with the model group, LVEF、LVFS and E/A of medial、high dose groups of Yi-Xin tai and Losartan Potassium group were significantly higher(P<0.01); IVS、 LVPW、LVIDs、 LVIDd were significantly lower (P<0.01);(3)compared with the model group, the cardiac index and left ventricular mass index of medial、high dose groups of Yi-Xin tai and Losartan Potassium group were significantly lower (P<0.01); compared with the low dose group, the cardiac index and left ventricular mass index of the middle、high dose groups of Yi-Xin tai and Losartan Potassium group were significantly lower (P<0.01);(4) compared with the model group, the concentration of myocardial intracellular calcium ion and the activity of CaN in myocardial tissue of the treatment groups were significantly lower(P<0.01);compared with the low dose group, the concentration of myocardial intracellular calcium ion and the the activity of CaN in myocardial tissue of the middle-. high dose groups of Yi-Xin tai and Losartan Potassium group were significantly lower (P<0.05or P<0.01);(5)compared with the model group, the protein expression of NFAT3> P-NFAT3、GATA4and C-Myc in myocardial tissue of the treatment groups were significantly lower (P<0.05or P<0.01); compared with the low dose group, the protein expression of NFAT3-. GATA4and C-Myc in myocardial tissue of the middle, high dose groups of Yi-Xin tai and Losartan Potassium group were significantly lower (P <0.05or P<0.01);(6)compared with the model group, the expression of NFAT3mRNA. GATA4mRNA, C-Myc mRNA of the middle, high dose groups of Yi-Xin tai and Losartan Potassium group were significantly lower (P<0.01); compared with the low dose group, the expression of NFAT3mRNA. GATA4mRNA. C-Myc mRNA of the middle, high dose groups of Yi-Xin tai and Losartan Potassium group were significantly lower (P<0.05or P<0.01)o(7) Compared with the model group, the damage of the myocardial cell of the treatment groups were alleviated; the infiltration of inflammatory cell reducted and ademo lightened.The myocardial ultrastructure was also significantly improved compared with the model group.Conclusion Yi-Xin tai can inhibit the myocardial remodeling and improve the cardiac function of the rabbit with chronic heart failure through inhibiting the Ca2+-CaN-NFAT3signal pathway.And the curative effect of medial and high dose groups of Yi-Xin tai is better than the low dose group.