INFLUENCE OF GINSENG SAPONIN ON THE CIRCADIAN RHYTHM IN BRAIN CATECHOLAMINE / 中国药理学通报

ABSTRACT

The circadian levels of norepinephrine ( NE ) and dopamiae (DA) in the whole brain were determined spectrofluorometrically in control mice and in mice pretreated with ginseng saponin. All animals were adapted for a minimum period of 2 weeks to an environmental room equipped with, an automatically timed 12h-light and 12h-dark illumination cycle before experiment. Data obtained at 4 h intervals for 48h spans were analyzed by the mean cosinor method.It has been proved that the catecholamine concentrations in the brain vary diurnally. The whole brain NE and DA contents were highest during the middle of dark phase and decreased to a low levels after the onset of light phase. In administration of ginseng saponin altered the circadian pattern and ( or ) levels of brain catecholamine over controls. In order to check the above results reserpine was injected to mice. The levels of NE and DA remarkedly depleted at the times studied, and they showed a significant circadian rhythms as well.It seems that ginseng saponin selectively modulates the circadian variations of brain NE and DA, and its effects may be as a cosinor function of the time of day.