ABSTRACT
Aim To investigate the antagonistic action o f total saponins of panaxnotoginseng(PNS) on cardiac hypertrophy and its nervous mechanism.Methods (1)cardiac hypertrophy of rats due to pressure overload was induced by constricting of abdominal aorta. There were five groups in the experiments. The rats in Group A(control group)were sham operated . Group B was aorta-constricted group.The rats in Group C,D,E were given ip PNS 50,100,150 mg?kg?d -1 for three weeks respectively. Three weeks later, We measured the heart-weight(HW),left ventricular weight(LVW), the ratio of HW/BW,LVW/BW (LVI) and the cardiomyocyte diameters(MD) after dyeing by HE color.(2)The effects of PNS on the fast excitatory postsynaptic potential(f-EPSP),membrane depolarization induced by application of acetylcholine (ACh),membrane potential and membrane resistance of the isolated Stellate ganglion(SG)of the rats were investigated by means of intracellular recording techniques. Results (1)HW/BW, LVI and MD of Group E were significantly lower than that of Group B(P0.05).(2)At the concentration of 0.10 ～0.16 g?L -1, PNS reversibly depressed the amplitude of f-EPSP, but the ACh depolarization,membrane potential and membrane resistance were not significantly altered by PNS. Conclusion PNS can prevent cardiac hypertrophy due to pressure overload in rats and this action may underline its inhibitory action on presyn aptic effect of regulating calcium influx.