Effects of positive modulators of α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA)-type glutamate receptors in a benzodiazepine-induced deficit of spatial discrimination in mice

J Psychopharmacol. 2012 Jun;26(6):845-56. doi: 10.1177/0269881111416692. Epub 2011 Sep 2.

Abstract

Imbalance between GABAergic and glutamatergic neurotransmission has been recently hypothesized to trigger memory decline related either to ageing or to Alzheimer's disease (AD). Thereby, benzodiazepine-induced anterograde amnesia has been construed as a model of hippocampal-related cognitive dysfunctions. Since spatial memory is altered both by ageing and by benzodiazepines such as alprazolam, we investigated the pharmacological sensitivity of alprazolam-induced deficit in a delayed spatial discrimination (SD) task, notably with positive allosteric modulators of α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA)-type glutamate receptors. We showed that alprazolam (0.1 mg/kg intraperitoneally) induced memory impairments as compared with vehicle-treated mice. The oral administration of modulators of AMPA receptors (IDRA-21: 10 mg/kg; S18986: 3 and 10 mg/kg) reversed the alprazolam-induced deficits. This study is first to show evidence that reference treatments of AD, such as memantine (a NMDA receptor antagonist) at 3 mg/kg per os (po) and donepezil (an acetylcholinesterase inhibitor) at 1 mg/kg po, also reversed the alprazolam-induced amnesia. Given such results, the SD task emerges as a valuable novel task to screen pro-cognitive compounds. Thus, we highlight the efficacy of modulators of AMPA-type glutamate receptors to counteract alprazolam-induced spatial deficits. These results could be viewed alongside the imbalance between excitation and inhibition observed during normal and pathological ageing.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Alprazolam / pharmacology
  • Amnesia / chemically induced
  • Amnesia / drug therapy*
  • Amnesia / metabolism
  • Animals
  • Behavior, Animal / drug effects
  • Benzothiadiazines / pharmacology*
  • Cognition Disorders / chemically induced
  • Cognition Disorders / drug therapy*
  • Discrimination, Psychological / drug effects*
  • Hippocampus / drug effects
  • Hippocampus / metabolism
  • Male
  • Memory / drug effects
  • Mice
  • Mice, Inbred C57BL
  • Receptors, AMPA / metabolism*
  • Receptors, Glutamate / metabolism*
  • Spatial Behavior / drug effects*

Substances

  • Benzothiadiazines
  • Receptors, AMPA
  • Receptors, Glutamate
  • Alprazolam