人参皂苷Rg2对异丙肾上腺素诱导的大鼠心室重构的保护作用

目的：探讨人参皂苷Rg2对异丙肾上腺素诱导的心室重构模型大鼠的保护作用。方法：将60只雄性Wistar大鼠随机分为对照组、心室重构模型组、人参皂苷Rg2（20、40、80 mg/kg）组和普萘洛尔（propranolol，15 mg/kg）组，n=10。采用多点皮下注射异丙肾上腺素85 mg/（kg·d），连续7 d，建立大鼠心室重构模型；对照组皮下注射等体积的生理盐水。此后按分组灌胃给药，每天1次，连续给药6 w后，使用八道生理记录仪测定血流动力学参数，并测定心脏重量和左心室重构指数。结果：与对照组相比，注射异丙肾上腺素后第7周时模型组大鼠颈动脉收缩压、舒张压、平均动脉压、心率、LVSP、+dp/dt_max、-dp/dt_max显著降低（P<0.01）；而HW/BW和LVW/BW、LVDP显著升高（P<0.01）。与模型组相比，人参皂苷Rg2低、中、高剂量组和普萘洛尔组大鼠颈动脉收缩压、舒张压、平均动脉压、心率、LVSP、+dp/dt_max、-dp/dt_max显著升高（P<0.05，P<0.01）；LVDP显著降低（P<0.01），而人参皂苷Rg2中、高剂量组和普萘洛尔组大鼠HW/BW和LVW/BW显著降低（P<0.01）。与普萘洛尔组相比，人参皂苷Rg2低剂量组收缩压、舒张压、平均动脉压显著降低（P<0.05，P<0.01）；人参皂苷Rg2低剂量组LVDP和高剂量组LVSP和+dp/dt_max显著升高（P<0.05，P<0.01）。结论：人参皂苷Rg2对异丙肾上腺素所致的心室重构模型大鼠具有改善作用。

Protective effects of ginsenoside-Rg2 on ventricular remodeling induced by isoproterenol in rats

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.