Tehran University of Medical Sciences Acta Medica Iranica 0044-6025 54 4 2016 05 10 226 232 EN Vahid Nikoui Experimental Medicine Research Center, Tehran University of Medical Sciences, Tehran, Iran. AND Razi Drug Research Center, Iran University of Medical Sciences, Tehran, Iran. Mehrak Javadi-Paydar Department of Pharmacology, School of Medicine, Tehran University of Medical Sciences, Tehran, Iran. Mahtab Salehi Department of Pharmacology, School of Medicine, Tehran University of Medical Sciences, Tehran, Iran. Selda Behestani Department of Pharmacology, School of Medicine, Tehran University of Medical Sciences, Tehran, Iran. Ahmad Reza Dehpour Experimental Medicine Research Center, Tehran University of Medical Sciences, Tehran, Iran. AND Department of Pharmacology, School of Medicine, Tehran University of Medical Sciences, Tehran, Iran. 2015 10 20 2016 01 18 Lithium is a drug used for the treatment of bipolar disorder. It has several mechanisms of action, and recently it is shown that lithium can antagonize the 5-HT1B/1D serotonin receptors. Sumatriptan is a 5-HT1B/1D receptor agonist used for the treatment of cluster headaches and migraine which might cause memory impairment as a potential side effect. In this study, effects of lithium on sumatriptan-induced memory impairment have been determined in a two-trial recognition Y-maze and passive avoidance tests. Male mice weighing 25-30 g were divided into several groups randomly. In Y-maze test, effects of lithium (1,5,10,20,40,80 mg/kg) and sumatriptan (1,5,10 mg/kg) were assessed on memory acquisition, then lithium (0.1,1,10 mg/kg) and sumatriptan (1,10 mg/kg) were studied in passive avoidance test. Effects of lithium (1mg/kg) on sumatriptan (10 mg/kg)-induced memory impairment were studied in both of tests. The present study demonstrated that sumatriptan impaired memory in Y-maze and passive avoidance tests (P<0.05, P<0.01, respectively). Lithium did not show any significant effect on memory function compared to saline-treated control group in both tests (P>0.05), but significantly reversed sumatriptan-induced memory impairment in Y-maze and passive avoidance tests (P<0.001, P<0.05, respectively). It is concluded that lithium reverses the sumatriptan-induced memory impairment probably through 5-HT1B/1D receptors antagonism. https://acta.tums.ac.ir/index.php/acta/article/view/5022 https://acta.tums.ac.ir/index.php/acta/article/download/5022/4773