Chronic treatment with mood-stabilizers attenuates abnormal hyperlocomotion of GluA1-subunit deficient mice

PLoS One. 2014 Jun 16;9(6):e100188. doi: 10.1371/journal.pone.0100188. eCollection 2014.

Abstract

Abnormal excitatory glutamate neurotransmission and plasticity have been implicated in schizophrenia and affective disorders. Gria1-/- mice lacking GluA1 subunit (encoded by Gria1 gene) of AMPA-type glutamate receptor show robust novelty-induced hyperactivity, social deficits and heightened approach features, suggesting that they could be used to test for anti-manic activity of drugs. Here, we tested the efficacy of chronic treatment with established anti-manic drugs on behavioural properties of the Gria1-/- mice. The mice received standard mood stabilizers (lithium and valproate) and novel ones (topiramate and lamotrigine, used more as anticonvulsants) as supplements in rodent chow for at least 4 weeks. All drugs attenuated novelty-induced locomotor hyperactivity of the Gria1-/- mice, especially by promoting the habituation, while none of them attenuated 2-mg/kg amphetamine-induced hyperactivity as compared to control diet. Treatment with lithium and valproate reversed the elevated exploratory activity of Gria1-/- mice. Valproate treatment also reduced struggling behaviour in tail suspension test and restored reciprocally-initiated social contacts of Gria1-/- mice to the level shown by the wild-type Gria1+/+ mice. Gria1-/- mice consumed slightly more sucrose during intermittent sucrose exposure than the wild-types, but ran similar distances on running wheels. These behaviours were not consistently affected by lithium and valproate in the Gria1-/- mice. The efficacy of various anti-manic drug treatments on novelty-induced hyperactivity suggests that the Gria1-/- mouse line can be utilized in screening for new therapeutics.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Anticonvulsants / pharmacology*
  • Antipsychotic Agents / pharmacology*
  • Behavior, Animal / drug effects*
  • Female
  • Hyperkinesis / prevention & control*
  • Lithium / pharmacology
  • Male
  • Maze Learning / drug effects
  • Mice
  • Mice, Knockout
  • Motor Activity / drug effects*
  • Receptors, AMPA / physiology*
  • Valproic Acid / pharmacology

Substances

  • Anticonvulsants
  • Antipsychotic Agents
  • Receptors, AMPA
  • Valproic Acid
  • Lithium
  • glutamate receptor ionotropic, AMPA 1

Grants and funding

The study was supported by the Academy of Finland, the Sigrid Juselius Foundation, the Orion research foundation and the Jane and Aatos Erkko Foundation (ERK). The support of the FinPharma Doctoral Program Drug Discovery section (MM) is gratefully acknowledged. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.