NMDA antagonists potentiate scopolamine-induced amnesic effect.
The effects of N-methyl-D-aspartate NMDA receptor antagonists on scopolamine-induced amnesia and on delay-interposed short-term memory performance were investigated using an 8-arm radial maze in rats. Scopolamine, a muscarinic antagonist, deteriorated the radial maze performance, while MK-801, an NMDA receptor channel blocker and CGS-19755, a competitive NMDA receptor antagonist, showed no obstruction to the spatial cognition in the non-delayed maze task. MK-801 (0.01-0.03 mg/kg, i.v.) and CGS-19755 (1-10 mg/kg, i.v.) significantly augmented scopolamine-induced deficit in the non-delayed maze task and impaired the short-term memory in the 5-min delay-interposed task. These results suggest that NMDA antagonists have a negative action on short-term memory and that the interaction between the NMDA and the central muscarinic system plays a role in modulating the cognitive function.
Li
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HB
Division of Pharmacology, Research Institute for Wakan-Yaku (Oriental Medicines), Toyama Medical and Pharmaceutical University, Japan.
Matsumoto
K
K
Tohda
M
M
Yamamoto
M
M
Watanabe
H
H
D000647:Amnesia / Q000139:chemically induced* / Q000523:psychology; D000818:Animals; D018680:Cholinergic Antagonists / Q000494:pharmacology*; D016291:Dizocilpine Maleate / Q000494:pharmacology; D004357:Drug Synergism; D018691:Excitatory Amino Acid Antagonists / Q000494:pharmacology; D007859:Learning Disabilities / Q000139:chemically induced / Q000523:psychology; D008297:Male; D018782:Maze Learning / Q000187:drug effects; D008570:Memory, Short-Term / Q000187:drug effects; D016202:N-Methylaspartate / Q000037:antagonists & inhibitors*; D010875:Pipecolic Acids / Q000494:pharmacology; D051381:Rats; D017208:Rats, Wistar; D012601:Scopolamine / Q000494:pharmacology*
D018680:Cholinergic Antagonists; D018691:Excitatory Amino Acid Antagonists; D010875:Pipecolic Acids; C053672:selfotel; D016202:N-Methylaspartate; D016291:Dizocilpine Maleate; D012601:Scopolamine