Schizandrin reverses memory impairment in rats.
The present study investigated the effect of schizandrin, a component of the fruit of Schizandra chinesis Baill (Fructus Schizandrae), on memory impairment in rats. Scopolamine (0.5 mg/kg, i.p.), a non-selective muscarinic receptor antagonist, markedly impaired spatial memory in an eight-arm radial maze. A higher dose of scopolamine (3 mg/kg, i.p.) also impaired the passive avoidance response. Schizandrin (1 and 10 mg/kg, p.o.) significantly reversed the scopolamine-induced impairment of spatial memory. Similarly, schizandrin (1 mg/kg, p.o.) significantly reversed the scopolamine-induced impairment of the passive avoidance response. Moreover, in mice, schizandrin (1 and 10 mg/kg, p.o.) enhanced tremors induced by oxotremorine, a muscarinic M(1) receptor agonist. Taken together these findings suggest that schizandrin reverses scopolamine-induced memory impairment, in part, by enhancing cholinergic function, and that schizandrin might be useful for treating memory deficits.
Egashira
Nobuaki
N
Department of Pharmacy, Kyushu University Hospital, Fukuoka 812-8582, Japan. n-egashi@pharm.med.kyushu-u.ac.jp
Kurauchi
Kouji
K
Iwasaki
Katsunori
K
Mishima
Kenichi
K
Orito
Kensuke
K
Oishi
Ryozo
R
Fujiwara
Michihiro
M
D000818:Animals; D001362:Avoidance Learning / Q000187:drug effects; D034242:Cyclooctanes / Q000737:chemistry / Q000494:pharmacology*; D004305:Dose-Response Relationship, Drug; D017705:Lignans / Q000737:chemistry / Q000494:pharmacology*; D008297:Male; D018782:Maze Learning / Q000187:drug effects; D008569:Memory Disorders / Q000139:chemically induced / Q000517:prevention & control*; D015394:Molecular Structure; D018727:Muscarinic Antagonists / Q000494:pharmacology; D010095:Oxotremorine / Q000494:pharmacology; D008517:Phytotherapy; D011083:Polycyclic Compounds / Q000737:chemistry / Q000494:pharmacology*; D051381:Rats; D017208:Rats, Wistar; D032141:Schisandra / Q000737:chemistry; D012601:Scopolamine
D034242:Cyclooctanes; D017705:Lignans; D018727:Muscarinic Antagonists; D011083:Polycyclic Compounds; D010095:Oxotremorine; D012601:Scopolamine; C011105:schizandrin