BACKGROUND AND AIM:

The critical role of cannabinoidergic and serotonergic systems of the amygdala in modulation of anxiety-like behaviors and emotional memory has already been demonstrated. The present study aimed to investigate the possible role of the basolateral amygdala (BLA) 5-HT3 and 5-HT4 serotonergic systems upon ACPA (CB1 cannabinoidreceptor agonist)-induced anxiolytic-like behaviors and emotional memory impairment using the elevated plus-maze (EPM) test-retest paradigm in male mice METHOD: bilateral guide-cannulae were implanted to allow intra-BLA microinjection of serotonergic agents RESULTS: the intraperitoneal injection of ACPA could induce anxiolytic-like behaviors and reduce the emotional memory formation. Intra-BLA injection of M-Chlorophenylbiguanide (M-Chl, a 5-HT3 serotonin receptor agonist) neither altered the anxiety-like behaviors nor the emotional memory formation by itself, while the higher dose of Y-25130 (a 5-HT3 serotonin receptor antagonist) reduced the emotional memory formation and locomotor activity but not the anxiety-like behaviors. Furthermore, injection of a higher dose of RS67333 and RS23597 (as 5-HT4 serotonin receptor agonist and antagonist, respectively) did not alter the anxiety-like behaviors, while reduced the emotional memory formation. In addition, the intra-BLA injection of M-Chl but not Y-25130 and RS67333 restored the ACPA-induced anxiolytic-like behaviors and emotional memory deficit, while a higher dose of RS67333 decreased the locomotor activity. Moreover, the intra-BLA microinjection of RS23597 could restore the ACPA-induced anxiolytic-like behaviors but not the emotional memory deficit CONCLUSION: based on our findings, ACPA seems to induce its anxiolytic-like behaviors and emotional memory formation deficits via activation and deactivation of the BLA 5-HT4 and 5-HT3 serotonin receptors.
Copyright © 2013. Published by Elsevier B.V.

PMID:

 24333573
[PubMed – as supplied by publisher]