Effects of methanol extract of Uncariae Ramulus et Uncus on ibotenic acid-induced amnesia in the rat.
In the present study, we investigated the effects of Uncariae Ramulus et Uncus (UR) on learning and memory in the Morris water maze task and the central cholinergic system of rats with excitotoxic medial septum (MS) lesion. In the water maze test, the animals were trained to find a platform in a fixed position during 6 days and then received a 60-s probe trial in which the platform was removed from the pool on the 7th day. Ibotenic lesion of the MS showed impaired performance of the maze test and severe cell losses in the septohippocampal cholinergic system (SHC), as indicated by decreased choline acetyltransferase-immunoreactivity and acetylcholinesterase-reactivity in the hippocampus. Daily administrations of UR (100 mg/kg, i.p.) for 21 consecutive days produced significant reversals of ibotenic acid-induced deficit in learning and memory. These treatments also reduced the loss of cholinergic immunoreactivity in the hippocampus induced by ibotenic acid. These results demonstrated that impairments of spatial learning and memory may be attributable to degeneration of SHC neurons and that UR ameliorated learning and memory deficits partly through neuroprotective effects on the central acetylcholine system. Our studies suggest that UR may be useful in the treatment of Alzheimer's disease.
Kim
Ji Hyun
JH
Graduate School of East-West Medical Science, College of Oriental Medicine, Kyung Hee University, Yongin-shi, Kyungki-do, Korea.
Chung
Jin Yong
JY
Lee
Young Jae
YJ
Park
Sepill
S
Kim
Jang Hyun
JH
Hahm
Dae Hyun
DH
Lee
Hye Jung
HJ
Shim
Insop
I
D000110:Acetylcholinesterase / Q000032:analysis; D000647:Amnesia / Q000139:chemically induced* / Q000188:drug therapy*; D000818:Animals; D006624:Hippocampus / Q000737:chemistry / Q000187:drug effects / Q000201:enzymology; D007051:Ibotenic Acid / Q000633:toxicity*; D008297:Male; D018782:Maze Learning / Q000187:drug effects / Q000502:physiology; D000432:Methanol / Q000627:therapeutic use; D010936:Plant Extracts / Q000302:isolation & purification / Q000494:pharmacology / Q000627:therapeutic use*; D051381:Rats; D017207:Rats, Sprague-Dawley; D032070:Uncaria
D010936:Plant Extracts; D007051:Ibotenic Acid; D000110:Acetylcholinesterase; D000432:Methanol