Abstract: Objective: To investigate the protective effects of ginsenoside-Rg2 on ventricular remodeling induced by isoproterenol (ISO) in rats.Methods: Sixty male Wistar rats were randomly divided into six groups, i.e. control group, ventricular remodeling model group,ginsenoside-Rg2 (20,40,80 mg/kg) groups and propranolol (15 mg/kg) group, with 10 rats in each group.The ventricular remodeling model was established in Wistar rats by subcutaneous injection with isoproterenol for seven days; the control group was given the same volume of normal saline. The rats were administrated intragastrically with ginsenoside-Rg2 or propranolol according to the group protocol above-mentioned after isoproterenol injection, once a day for 6 weeks. Then, the hemodynamic parameters were tested by an eight channel physiological recorder, and the heart weight was weighed and the left ventricular remodeling index was calculated.Results: On the 7th week after ISO injection, systolic blood pressure (SBP), diastolic blood pressure (DBP), mean blood pressure (MBP), heat rate, left ventricular systolic pressure (LVSP), +dp/dt_max, -dp/dt_max in the model group were lower than those of control group (P<0.01), however, heart weight/body weight (HW/BW), left ventricular weight/body weight (LVW/BW) and left ventricular end-diastolic pressure (LVEDP) were higher significantly than those of control group (P<0.01). The levels of SBP, DBP, MBP, HR, LVSP, +dp/dt_max, -dp/dt_max in ginsenoside-Rg2 low, medium and high dose groups and propranolol group were higher than those of model group (P<0.05, P<0.01); while the levels of LVDP were lower than that of model group (P<0.05, P<0.01). The levels of HW/BW and LVW/BW in ginsenoside-Rg2 medium and high dose groups and propranolol group were lower than those of model group (P<0.01). Compared with propranolol group, the levels of SBP, DBP, MBP were significantly decreased in ginsenoside-Rg2 low dose group (P<0.05, P<0.01); the level of LVEDP in ginsenoside-Rg2 low dose group, the levels of LVSP and +dp/dt_max in ginsenoside-Rg2 high dose group were obviously increased (P<0.05, P<0.01).Conclusion: Ginsenoside-Rg2 can alleviate the ventricular remodeling induced by isoproterenol in rats.

Key words: ginsenoside-Rg2, isoproterenol, ventricular remodeling, hemodynamics, rat