Study the Effect of Endocannabinoid System on Rat Behavior in Elevated Plus-Maze

introduction: previous studies have shown that cannabinoidergic system is involved in anxiety.however, there are controversial reports in the experimental studies. the aim of this study is toevaluate the effect of pharmacological stimulation or blocking of cb1 receptors and inhibitionof endocannabinoid degradation in anxiety like behavior in elevated plus-maze (epm) test in rat.the epm is one of the most widely used animal models of anxiety. methods: male wistar rats were randomly allocated to ten groups. different groups of animalsintraperitoneally received win-55212 (0.3, 1 and 5 mg/kg) as cb1 receptor agonist, am-251 (0.3, 1 and 5 mg/kg) as cb1 receptor antagonist, urb-597 (0.03, 0.1 and 0.3 mg/kg) asendocannabinoid breakdown inhibitor or saline (as control group) 30 min before submitting intoepm test. results: the results showed that compared to the control group, win-55212 (1 and 5 mg/kg)and urb-597 (0.1 and 0.3 mg/kg) significantly increased both of the time and percentage ofentries into open arms. am-251 (1 and 5 mg/kg) significantly decreased the time and percentageof entries into open arms in the epm test. these substances have no effects on the total distancecovered by animals and number of closed arm entries. discussion: it is concluded that activation of cannabinoid receptor exert anxiolytic effect whileblocking of cannabinoid receptor resulted in anxiety behavior. the locomotor activity was notsignificantly changed by cannabinoid system. it is suggested that potentiation of cannabinoidsystem may be therapeutic strategy for the anxiety behavior.