, Volume 85, Issue 1, pp 102–105 | Cite as

Clonidine induced sedation is not altered by repeated stress in the RHA/iop and RLA/iop strains of rats

  • Michael J. Durcan
  • Iain C. Campbell
  • Bina Chitkara
Original Investigations


An hypothesis that repeated stress results in central changes in α2-adrenoceptor sensitivity was investigated using a behavioural test. Stressed (immobilisation for 2 h/day for 7 days) and unstressed rats from the RHA/iop and RLA/iop strains were tested for the sedative effects of the α2-adrenoceptor agonist clonidine on Y-maze behaviour. The measures used were number of lines crossed, arm entries and rearing. The stressed animals showed higher scores for line crossings and rearing; but the only significant difference between the strains was for rearing, which was higher for RHA/iop. Clonidine significantly depressed all the measures of activity. However, there was no evidence of an interaction of the drug with stress for any of the measures. It is concluded that neither repeated stress nor genetic differences in the ability to cope with stress influence the behavioural effects of clonidine. This suggests that stress responses are not related to the central α2-adrenoceptor system.

Key words

Clonidine Sedation Activity RHA/iop and RLA/iop Strains Adrenoceptors Stress Rat 


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Copyright information

© Springer-Verlag 1985

Authors and Affiliations

  • Michael J. Durcan
    • 1
  • Iain C. Campbell
    • 1
  • Bina Chitkara
    • 1
  1. 1.Departments of Psychology and BiochemistryInstitute of PsychiatryLondonUK

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