Faezeh Kafi - Department of Biology, Faculty of Basic Sciences, kharazmi University,Tehran, Iran
Mohammad Nasehi - Institute for Cognitive Science Studies (ICSS), Tehran, Iran
Mohammad Reza Zarrindast - Department of Neuroscience, School of Advanced Medical Technologies and Department of Pharmacology, School of Medicine, Tehran University of Medical Sciences, Tehran, Iran, dInstitute for Cognitive Science Studies (ICSS), Tehran, Iran
Parvin Rostami - Department of Biology, Faculty of Basic Sciences, kharazmi University,Tehran, Iran

Background and Aim : Several studies indicated that cannabinoidergic system has a critical role in regulation of cognitive and non cognitive behaviors such as learning and memory formation in the different brain regions including hippocampus. Moreover, several neurotransmitter systems such as serotonin involved in the cannabinoid responses. Serotonergic fibers innervate a variety of brain regions including the hippocampus and thus influence hippocampal behaviors formation. Therefore, the aim of present study is, to investigate the effects of ventral hippocampal (CA3) serotoninegic system on ACPA (selective CB1 cannabinoid receptor agonist)-induced amnesia.Methods : Male mice weighing 20-25g used in these experiments. The drug was injected into CA3 (bilaterally) in a total volume of 1μl/mouse ( 0.5 μl in each side) over a 60s period in mice, meanwhile, ACPA was injected intraperitoneally (i.p.) in a volume of 1ml/kg. We used step down task for assessment of memory formation.Results : The results showed that ACPA injected intraperitoneally (2 and 5 ng/mouse) did not significantly alter on memory behavior, while in highest dose of the drug (10 ng/mouse) induced amnesia. Furthermore, intra-ventral hippocampal (CA3) injection of serotonin (5-HT-4) agonist on their own (0.625,1.25 ng/mouse) had no effect, but in highest dose (2ng/mouse) induced amnesia. However, sub threshold dose of (5-HT-4) agonist (0.625ng/mouse) with doses of ACPA(5,10 ng/kg) increased amnesia impairment of induced-ACPA.Conclusion : The findings demonstrate that possible involvement of CA3 serotonergic system on ACPA induced amnesia.

The findings demonstrate that possible involvement of CA3 serotonergic system on ACPA induced amnesia