This Article Full Text (PDF) All Versions of this Article: 0269881107083848v1 0269881107083848v2 22/8/865    most recent References Alert me when this article is cited Alert me if a correction is posted Citation Map Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Add to Saved Citations Download to citation manager Request Permissions Request Reprints Add to My Marked Citations Citing Articles Citing Articles via Google Scholar Citing Articles via Scopus Google Scholar Articles by Zarrindast, M-R. Articles by Ahamadi, S. Search for Related Content PubMed PubMed Citation Articles by Zarrindast, M-R. Articles by Ahamadi, S. Social Bookmarking                         What's this?

Possible involvement of µ-opioid receptors in effect of lithium on inhibitory avoidance response in mice

Department of Pharmacology, School of Medicine and Iranian National Center for Addiction Studies, Tehran University of Medical Sciences, zarinmr{at}ams.ac.ir, School of Cognitive Science, Institute for Studies Theoretical Physics and Mathematics and Institute for Cognitive Science Studies, Tehran, Iran

A. Lahmi

Department of Basic science, Tehran North Unit, Azad University, Tehran, Iran

S. Ahamadi

Department of Biological Science and Biotechnology, Faculty of Science, University of Kurdistan, Sanandaj, Iran

In the present study, effects of intracerebroventricular (i.c.v.) injections of µ-opioid receptor agonist and antagonist on lithium state-dependency were investigated. For memory assessment, a one-trial step-down inhibitory avoidance task was used in adult male NMRI mice. Intraperitoneal (i.p.) administration of lithium (10 mg/kg) after training impaired memory when retrieval was tested 24 h later. The memory impairment was reversed by pretest administration of the same dose of lithium, suggesting state-dependency induced by lithium. In addition, i.c.v. administration of both lithium (2 and 4 µg/mouse, i.c.v.) and morphine (3 and 6 µg/mouse, i.c.v.) before the test reversed memory impairment induced by post-training lithium (10 mg/kg, i.p.). On the other hand, pretest administration of naloxone (1 and 2 mg/kg) which had no effects alone on inhibitory avoidance response, prevented the improving effects of both morphine (3 µg/mouse, i.c.v.) and lithium (2 µg/mouse, i.c.v.) on memory retrieval. The results suggest that the µ-opioid receptors in the central nervous system may be involved in the retrieval of lithium state-dependent learning.

Key Words: lithium • morphine • naloxone • state-dependency • memory retrieval • mouse

This version was published on November 1, 2008

Journal of Psychopharmacology, Vol. 22, No. 8, 865-871 (2008)
DOI: 10.1177/0269881107083848


CiteULike    Complore    Connotea    Del.icio.us    Digg    Reddit    Technorati    Twitter    What's this?