Advertisement

Psychopharmacology

, Volume 132, Issue 3, pp 227–236 | Cite as

CCK-B receptors in the limbic system modulate the antidepressant-like effects induced by endogenous enkephalins

  • Claire Smadja
  • Fernando Ruiz
  • Pascale Coric
  • Marie Claude Fournié-Zaluski
  • Bernard P. Roques
  • R. Maldonado
ORIGINAL INVESTIGATION

Abstract

Systemic administration of RB 101, a complete inhibitor of enkephalin catabolism, has been reported to induce antidepressant-like responses in mice which were potentiated by an ineffective dose of a CCK-B antagonist. The aim of this study was to investigate the neuroanatomical substrate involved in the facilitatory effects induced by CCK-B antagonists on RB 101 behavioural responses. Thus, the CCK-B antagonist PD-134,308 was locally administered into different brain structures (anterior nucleus accumbens, central amygdala and caudate nucleus) and its effects on the antidepressant-like response induced by systemic administration of RB 101 were evaluated in the conditioned suppression of motility (CSM) test in rats. RB 101 administered alone by the IV route decreased the CSM in rats, as previously obtained in mice. Systemic administration of a non effective dose of PD-134,308 facilitated the antidepressant-like effect induced by RB 101. Local injection of PD-134,308 into the anterior nucleus accumbens, the central amygdala or the caudate nucleus did not modify CSM. The antidepressant-like effects elicited by RB 101 in this test were potentiated by PD-134,308 after microinjection in the anterior nucleus accumbens and central amygdala, but not in the caudate nucleus. All these effects were observed only in shocked animals. The present results suggest that the mesolimbic system, particularly the anterior nucleus accumbens and the central amygdala, seems to play an important role in the interaction occurring between the endogenous CCK and opioid system in the control of behavioural responses.

Key words Antidepressant-like effects Enkephalin degrading enzymes RB 101 PD-134 308 CCK-B receptors Anterior nucleus accumbens Central amygdala Caudate nucleus 

Preview

Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.

Copyright information

© Springer-Verlag Berlin Heidelberg 1997

Authors and Affiliations

  • Claire Smadja
    • 1
  • Fernando Ruiz
    • 1
  • Pascale Coric
    • 1
  • Marie Claude Fournié-Zaluski
    • 1
  • Bernard P. Roques
    • 1
  • R. Maldonado
    • 1
  1. 1.Département de Pharmacochimie Moléculaire et Structurale, INSERM U266, CNRS URA D 1500, UFR des Sciences Pharmaceutiques et Biologiques, 4, Avenue de l’observatoire, F-75270 Paris Cedex 06, France Fax (+33)1/43 26 69 18FR

Personalised recommendations