Suppressive effect of Yokukansan on excessive release of glutamate and aspartate in the hippocampus of zinc-deficient rats.
Yokukansan (TJ-54), a herbal medicine, has been used as a cure for insomnia and irritability in children. Yokukansan also improves behavioral and psychological symptoms such as agitation, aggression and irritability in patients with dementia including Alzheimer's disease, in which the glutamatergic neurotransmitter system is perturbed. However, the action of Yokukansan in synaptic neurotransmission is unknown. In the present study, the action of Yokukansan in the glutamatergic neurotransmitter system was examined in zinc-deficient rats, a neurological disease model, in which the glutamatergic neurotransmitter system is perturbed. Administration of Yokukansan significantly suppressed the increase in extracellular concentrations of glutamate and aspartate in the hippocampus after stimulation with 100 mM KCl, but not the increase in extracellular concentrations of glycine and taurine, suggesting that Yokukansan is involved in modulation of excitatory neurotransmitter systems. The present study demonstrates that Yokukansan is a possible medicine for prevention or cure of neurological diseases associated with excitotoxicity.
Department of Medical Biochemistry, School of Pharmaceutical Sciences, University of Shizuoka, Shizuoka, Japan. takedaa@u-shizuoka-ken.ac.jp
Atsushi
A
Takeda
Hiromasa
H
Itoh
Haruna
H
Tamano
Mitsutoshi
M
Yuzurihara
Naoto
N
Oku
D000818:Animals; D001224:Aspartic Acid / Q000032:analysis / Q000378:metabolism*; D004365:Drugs, Chinese Herbal / Q000008:administration & dosage*; D045604:Extracellular Fluid / Q000737:chemistry; D018698:Glutamic Acid / Q000032:analysis / Q000378:metabolism*; D005998:Glycine / Q000032:analysis; D006624:Hippocampus / Q000187:drug effects / Q000378:metabolism*; D008297:Male; D017551:Microdialysis; D009422:Nervous System Diseases / Q000517:prevention & control; D008517:Phytotherapy; D011189:Potassium Chloride / Q000008:administration & dosage; D051381:Rats; D017208:Rats, Wistar; D009435:Synaptic Transmission / Q000187:drug effects; D013654:Taurine / Q000032:analysis; D015032:Zinc / Q000172:deficiency*
D004365:Drugs, Chinese Herbal; C524644:Yi-Gan San; D013654:Taurine; D001224:Aspartic Acid; D018698:Glutamic Acid; D011189:Potassium Chloride; D015032:Zinc; D005998:Glycine