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Psychopharmacology

, Volume 84, Issue 2, pp 287–288 | Cite as

Behavioural responsiveness to muscimol and apomorphine 2 months after prolonged treatment with estradiol in rats

  • V. Cuomo
  • R. Cagiano
  • J. Apud
  • C. Masotto
  • G. Racagni
Rapid Communication

Abstract

Two months after prolonged administration of estradiol (ES) in female rats the behavioural responsiveness to muscimol, a GABA receptor stimulating agent, and to apomorphine, a dopamine receptor agonist, was significantly altered. In particular, the decrease in locomotor activity induced by a challenge dose of muscimol (0.5–1 mg/kg) was significantly attenuated in ES-pretreated animals. Conversely, the intensity of stereotyped behaviour elicited by a challenge dose of apomorphine (1 mg/kg) was significantly increased in ES-pretreated rats. The behavioural alterations in the response to muscimol and apomorphine presumably result from the production of central GABA receptor subsensitivity and dopamine receptor supersensitivity respectively, induced by the prolonged ES administration.

Key words

Prolonged estradiol treatment Behaviour Rat Muscimol Apomorphine 

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Copyright information

© Springer-Verlag 1984

Authors and Affiliations

  • V. Cuomo
    • 1
  • R. Cagiano
    • 1
  • J. Apud
    • 2
  • C. Masotto
    • 2
  • G. Racagni
    • 2
  1. 1.Institute of PharmacologyUniversity of BariBariItaly
  2. 2.Institute of Pharmacology and PharmacognosyUniversity of MilanItaly

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