The ameliorating effect of oroxylin A on scopolamine-induced memory impairment in mice.
Oroxylin A is a flavonoid and was originally isolated from the root of Scutellaria baicalensis Georgi., one of the most important medicinal herbs in traditional Chinese medicine. The aim of this study was to investigate the ameliorating effects of oroxylin A on memory impairment using the passive avoidance test, the Y-maze test, and the Morris water maze test in mice. Drug-induced amnesia was induced by administering scopolamine (1 mg/kg, i.p.) or diazepam (1 mg/kg, i.p.). Oroxylin A (5 mg/kg) significantly reversed cognitive impairments in mice by passive avoidance and the Y-maze testing (P<.05). Oroxylin A also improved escape latencies in training trials and increased swimming times and distances within the target zone of the Morris water maze (P<.05). Moreover, the ameliorating effects of oroxylin A were antagonized by both muscimol and diazepam (0.25 mg/kg, i.p., respectively), which are GABA(A) receptor agonists. Furthermore, oroxylin A (100 microM) was found to inhibit GABA-induced inward Cl(-) current in a single cortical neuron. These results suggest that oroxylin A may be useful for the treatment of cognitive impairments induced by cholinergic dysfunction via the GABAergic nervous system.
Kim
Dong Hyun
DH
Department of Oriental Pharmaceutical Science and Kyung Hee East-West Pharmaceutical Research Institute, College of Pharmacy, Kyung Hee University, Dongdaemoon-Ku, Seoul, Korea.
Jeon
Su Jin
SJ
Son
Kun Ho
KH
Jung
Ji Wook
JW
Lee
Seungjoo
S
Yoon
Byung Hoon
BH
Lee
Jong-Ju
JJ
Cho
Young-Wuk
YW
Cheong
Jae Hoon
JH
Ko
Kwang Ho
KH
Ryu
Jong Hoon
JH
D000647:Amnesia / Q000139:chemically induced / Q000517:prevention & control; D000704:Analysis of Variance; D000818:Animals; D001362:Avoidance Learning / Q000187:drug effects* / Q000502:physiology; D003072:Cognition Disorders / Q000188:drug therapy / Q000503:physiopathology; D004365:Drugs, Chinese Herbal / Q000494:pharmacology*; D005260:Female; D005419:Flavonoids / Q000494:pharmacology*; D008297:Male; D018782:Maze Learning / Q000187:drug effects* / Q000502:physiology; D008568:Memory / Q000187:drug effects* / Q000502:physiology; D051379:Mice; D008813:Mice, Inbred ICR; D018727:Muscarinic Antagonists; D051381:Rats; D017207:Rats, Sprague-Dawley; D011930:Reaction Time / Q000187:drug effects / Q000502:physiology; D011963:Receptors, GABA-A / Q000187:drug effects* / Q000502:physiology; D012601:Scopolamine; D018709:Statistics, Nonparametric
D004365:Drugs, Chinese Herbal; D005419:Flavonoids; D018727:Muscarinic Antagonists; D011963:Receptors, GABA-A; C080669:5,7-dihydroxy-6-methoxy-2-phenylchromen-4-one; D012601:Scopolamine