Psychopharmacology

, Volume 228, Issue 1, pp 31–42

The atypical antipsychotic risperidone reverses the recognition memory deficits induced by post-weaning social isolation in rats

Authors

  • Allison L. McIntosh
    • School of Biomedical SciencesMedical School, Queen’s Medical Centre, University of Nottingham
  • Theresa M. Ballard
    • F. Hoffmann-La Roche AG, pRED, Pharma Research & Early Development, DTA Neuroscience
  • Lucinda J. Steward
    • F. Hoffmann-La Roche AG, pRED, Pharma Research & Early Development, DTA Neuroscience
  • Paula M. Moran
    • School of PsychologyUniversity of Nottingham, University Park
    • School of Biomedical SciencesMedical School, Queen’s Medical Centre, University of Nottingham
Original Investigation

DOI: 10.1007/s00213-013-3011-2

Cite this article as:
McIntosh, A.L., Ballard, T.M., Steward, L.J. et al. Psychopharmacology (2013) 228: 31. doi:10.1007/s00213-013-3011-2

Abstract

Rationale

Rearing rats in isolation from weaning is an established preclinical neurodevelopmental model which induces behavioural deficits with apparent translational relevance to some core symptoms of schizophrenia.

Objective

This study evaluated the ability of the atypical antipsychotic risperidone to reverse behavioural deficits induced by post-weaning social isolation of rat pups and to further characterise the predictive validity of this model.

Method

Forty-five male Lister hooded rats were housed in groups of 3–4 (n = 16) or singly (n = 29) for 4 weeks immediately after weaning on postnatal day (PND) 22–24. On PND 51, novel cage-induced locomotor activity (LMA) was assessed to subdivide rats into groups balanced for behavioural response. On PNDs 58, 59, 65 and 72, rats received either vehicle (1 ml/kg; i.p.) or risperidone (0.2 or 0.5 mg/kg; i.p.) 30 min prior to testing in LMA, novel object discrimination (NOD), prepulse inhibition (PPI) of acoustic startle and conditioned emotional response (CER) learning paradigms, respectively.

Results

Isolation rearing had no effect on PPI, but produced LMA hyperactivity and impaired NOD and CER compared to group-housed controls. Risperidone caused a dose-dependent reduction in LMA, irrespective of rearing condition, but selectively reversed the NOD deficit in isolation-reared rats. Risperidone did not reverse the isolation rearing-induced CER deficit.

Conclusions

Similar to its clinical profile, risperidone only partially reverses the schizophrenic symptomology; since it reversed some, but not all, of the learning and memory deficits induced by post-weaning isolation, the isolation rearing model may be useful to predict antipsychotic activity of novel therapeutic agents.

Keywords

Risperidone Post-weaning social isolation Schizophrenia Cognition Recognition memory

Abbreviations

ANOVA

Analysis of variance

CER

Conditioned emotional response

GABA

γ-Aminobutyric acid

ITI

Inter-trial interval

LMA

Locomotor activity

NOD

Novel object discrimination

Prh

Perirhinal cortex

PND

Postnatal day

PPI

Prepulse inhibition

SI

Socially isolated

GH

Group-housed

Copyright information

© Springer-Verlag Berlin Heidelberg 2013