Effect of the Combination of Ginseng, Oriental Bezoar and Glycyrrhiza on Autonomic Nervous Activity as Evaluated by Power Spectral Analysis of HRV and Cardiac Depolarization-Repolarization Process

BACKGROUND: Ginseng, oriental bezoar and glycyrrhiza are the most widespread herbs often used in Kampo. These three herbs have been used for a Kampo for a thousand years and a number of pharmacological and clinical studies have reported about their effects. However, it has not been previously described how the combination of these most commonly used herbs affects the autonomic nervous system (ANS). OBJECTIVE: This is a randomized, double-blind, placebo-controlled experiment to examine the acute effects of Kampo on autonomic nervous activity by using power spectral analysis of heart rate variability (HRV) and cardiac depolarization-repolarization time intervals in humans. DESIGN: Ten healthy men volunteered to participate in this study. The Kampo at a dose of two capsules contained the following ingredients: powdered ginseng 250 mg, powdered oriental bezoar 50 mg, and powdered glycyrrhiza 50 mg. The placebo capsules contained corn starch. A CM5 lead ECG was recorded before, and 30 min and 60 min after the oral administration of Kampo or a placebo on different days. RESULTS: HF power (high frequency component in the HRV) was significantly increased and HR (heart rate) was significantly decreased after taking Kampo at 60 min (p<0.05) compared with the placebo. TP (total power) and LF power (low frequency component in the HRV) did not change significantly between the Kampo and placebo, and there were also no statistically significant differences in heart-rate-corrected ECG QT interval (QTc) or recovery time (RTc) between the Kampo and placebo. However, we observed that there was a tendency of decreased QTc interval and RTc after taking Kampo at 60 min compared with response of the placebo (p<0.1). CONCLUSIONS: These results indicated that the Kampo mainly potentiated parasympathetic nervous activity and may be useful for cardiovascular health.