Effects of Toki-shakuyaku-san on electric footshock stress in ovariectomized mice.
In the present study, ovariectomized mice were exposed to electric footshock stress for 7 days, and the duration of sodium pentobarbital-induced sleep was measured on the day following the last stress exposure. In ovariectomized mice, the duration of sodium pentobarbital-induced sleep before exposure to stress did not differ markedly from that in the sham-operation group. After exposure to stress, however, the duration of sodium pentobarbital-induced sleep in ovariectomized mice was shortened significantly, compared to the ovariectomized mice without stress. When the effect of Toki-shakuyaku-san on the stress-induced shortening of sleep time was studied, it was found that the shortening of the sleep time was suppressed by treatment with Toki-shakuyaku-san. In ovariectomized mice, the increase in hypothalamic noradrenaline (NA) turnover in response to stress was significantly greater than that in mice with intact ovaries. The stress-induced enhancement of NA turnover was suppressed significantly by Toki-shakuyaku-san in a dose-dependent manner, beginning with a low dose level. When effect of 17Beta-estradiol on the stress induced-shortening of sleep time was examined in ovariectomized mice, by high doses of 17Beta-estradiol the shortening of the sleep time was prolonged. A major difference between 17Beta-estradiol and Toki-shakuyaku-san was the marked uterine weight gain observed following 17Beta-estradiol treatment despite no effect of Toki-shakuyaku-san on uterine weight. The results in this study suggest that Toki-shakuyaku-san may reduce menopausal symptoms by a mechanism different from that of estrogen.
Iizuka
S
S
Central Research Laboratories, Tsumura & Co., Ibaraki, Japan.
Ishige
A
A
Komatsu
Y
Y
Matsumiya
T
T
Inazu
M
M
Takeda
H
H
D000818:Animals; D004365:Drugs, Chinese Herbal / Q000494:pharmacology*; D004597:Electroshock; D005260:Female; D007031:Hypothalamus / Q000378:metabolism; D051379:Mice; D008813:Mice, Inbred ICR; D009638:Norepinephrine / Q000378:metabolism; D009929:Organ Size; D010052:Ovariectomy; D010424:Pentobarbital / Q000494:pharmacology; D010946:Plants, Medicinal; D012890:Sleep / Q000187:drug effects; D013312:Stress, Physiological / Q000503:physiopathology*
D004365:Drugs, Chinese Herbal; C413220:toki-shakuyaku-san; D010424:Pentobarbital; D009638:Norepinephrine