title: Arcaine and MK-801 make recall state-dependent in rats.
abstract: BACKGROUND
  The polyamines putrescine, spermidine, and spermine are a group of aliphatic amines that may act as physiological modulators of the N-methyl-D-aspartate (NMDA) receptor, a glutamate receptor implicated in memory formation and consolidation. Arcaine is a competitive antagonist of the polyamine binding site at the NMDA receptor, the post-training administration of which impairs memory of various tasks.
  
  
  OBJECTIVE
  In this study, we investigated whether the administration of arcaine and MK-801 alters the memory of the step-down inhibitory avoidance task, and whether the effects of these NMDA antagonists involve state-dependency mechanisms, in adult male Wistar rats.
  
  
  RESULTS
  The administration of arcaine (30 mg/kg, i.p.) or MK-801 (0.03 mg/kg, i.p.) immediately after training impaired inhibitory avoidance performance at testing. Arcaine- and MK-801-induced performance impairment was reversed by the administration of arcaine (30 mg/kg, i.p.) and MK-801 (0.03 mg/kg, i.p.), respectively, 30 min before testing. Response transfer also occurred if arcaine substituted MK-801 at testing, and vice-versa.
  
  
  CONCLUSIONS
  These results suggest that arcaine and MK-801 induce state-dependent recall and that, probably due to their ability to decrease NMDA receptor function, one drug can substitute for the other at testing, demonstrating a cross-state dependency between arcaine and MK-801.
authors.affiliation: Centro de Ciências Naturais e Exatas, Departamento de Química, Universidade Federal de Santa Maria, Santa Maria, RS, Brazil.
authors.forename: Ana Paula Chiapinotto
authors.initials: AP
authors.lastname: Ceretta
authors.forename: Keli
authors.initials: K
authors.lastname: Camera
authors.forename: Carlos Fernando
authors.initials: CF
authors.lastname: Mello
authors.forename: Maribel Antonello
authors.initials: MA
authors.lastname: Rubin