Yokukansan inhibits social isolation-induced aggression and methamphetamine-induced hyperlocomotion in rodents.
Behavioral and psychological symptoms of dementia (BPSD) are commonly seen in patients with Alzheimer's disease (AD) and other forms of senile dementia. BPSD have a serious impact on the quality of life of dementia patients, as well as on that of their caregivers. However, effective drug therapy for BPSD has not been established. Recently, the traditional Japanese medicine Yokukansan (YKS, Yi-gan san in Chinese) has been reported to improve BPSD, such as aggression, agitation, irritability, and hallucinations, in a randomized, single-blind, placebo-controlled study. However, the psychopharmacologic effects of YKS remain unexplored. In the present study, we investigated the effects of YKS on social isolation-induced aggressive behavior and methamphetamine- or MK-801-induced hyperlocomotion in rodents. Social isolation markedly induced aggressive behavior in male Wistar rats. Quetiapine at a dose of 10 mg/kg (per os (p.o.)) significantly inhibited this social isolation-induced aggressive behavior. YKS (100, 300 mg/kg, p.o.) also significantly inhibited the aggressive behavior. Moreover, risperidone (0.1 mg/kg, p.o.) significantly inhibited methamphetamine- or MK-801-induced hyperlocomotion in mice. YKS (300 mg/kg, p.o.) inhibited methamphetamine-induced hyperlocomotion, while YKS at the same dose had no effect on MK-801-induced hyperlocomotion. These findings suggest that YKS may be useful for the treatment of aggression and agitation, and that the psychopharmacologic effects of YKS might be mediated, in part, by inhibiting the activity of the dopaminergic system.
Uchida
Naoki
N
Department of Psychiatry, Fukuoka University School of Medicine, Japan.
Egashira
Nobuaki
N
Iwasaki
Katsunori
K
Ishibashi
Ayumi
A
Tashiro
Ryosuke
R
Nogami
Ai
A
Manome
Naomi
N
Abe
Moe
M
Takasaki
Kotaro
K
Mishima
Kenichi
K
Takata
Jiro
J
Oishi
Ryozo
R
Nishimura
Ryoji
R
Fujiwara
Michihiro
M
D000374:Aggression / Q000187:drug effects*; D000818:Animals; D004365:Drugs, Chinese Herbal / Q000494:pharmacology* / Q000627:therapeutic use; D006948:Hyperkinesis / Q000139:chemically induced / Q000188:drug therapy*; D008297:Male; D008694:Methamphetamine; D051379:Mice; D051381:Rats; D017208:Rats, Wistar; D012934:Social Isolation; D013315:Stress, Psychological / Q000188:drug therapy* / Q000523:psychology
D004365:Drugs, Chinese Herbal; C524644:Yi-Gan San; D008694:Methamphetamine