title: Huperzine A reverses scopolamine- and muscimol-induced memory deficits in chick.
abstract: OBJECTIVE
  To study the effects of huperzine A on disruption of spatial memory induced by scopolamine (a muscarinic antagonist) and muscimol (a GABAA agonist) in passive avoidance task.
  
  
  METHODS
  One-trial passive avoidance task was used to investigate the effects of huperzine A. The avoidance rate was used to evaluate memory retention.
  
  
  RESULTS
  Both scopolamine (100 ng) and muscimol (50 ng), injected intracranially 5 min before training, resulted in a decreased avoidance rate. Huperzine A (25 ng), injected intracranially 15 min before training, reversed memory deficits induced by scopolamine and muscimol at 30 min after training, and this reversal persisted at least 1 h. The improving effects of huperzine A exhibited a bell-shaped dose-response curve.
  
  
  CONCLUSIONS
  Huperzine A improved the process of memory formation not only by acting as a highly potent and selective inhibitor of AChE, but also by antagonizing effects mediated through the GABAA receptor.
authors.affiliation: Institute of Psychology, Chinese Academy of Sciences, Beijing 100101, China. gaoy@s1000.psych.ac.cn
authors.forename: Y
authors.initials: Y
authors.lastname: Gao
authors.forename: X C
authors.initials: XC
authors.lastname: Tang
authors.forename: L C
authors.initials: LC
authors.lastname: Guan
authors.forename: P Z
authors.initials: PZ
authors.lastname: Kuang
mesh_terms: D000470:Alkaloids; D000647:Amnesia / Q000139:chemically induced / Q000188:drug therapy*; D000818:Animals; D001362:Avoidance Learning / Q000187:drug effects*; D002645:Chickens; D002800:Cholinesterase Inhibitors / Q000494:pharmacology*; D018755:GABA Agonists; D008297:Male; D018727:Muscarinic Antagonists; D009118:Muscimol; D012153:Retention, Psychology / Q000187:drug effects*; D012601:Scopolamine / Q000037:antagonists & inhibitors; D012717:Sesquiterpenes / Q000494:pharmacology*
chemical_list: D000470:Alkaloids; D002800:Cholinesterase Inhibitors; D018755:GABA Agonists; D018727:Muscarinic Antagonists; D012717:Sesquiterpenes; C050426:huperzine A; D009118:Muscimol; D012601:Scopolamine