Anxiolytic- and antidepressant-like effects of the ethanolic extract from Citrus limon plant widely used in Northeastern Brazil

Anxiolytic and antidepressant effects and acute toxicity of ethanolic extract (EE) from Citrus limon were studied in mice. Anxiolytic activity was evaluated using open field and elevated plus-maze tests. The antidepressant effect of the extract was studied by forced swimming test in mice. Phytochemical screening of the ethanolic extracts indicated the presence of cumarin and triterpenoids/steriods. In the open field test, the oral route administration EE alone showed significant sedative and antidepressant activities in mice (p < 0.05). EE did not alter motor coordination. The EE, at three doses tested, showed antidepressant effect and produced decrease in immobility time. It is concluded that the EE of the aerial parts of C. limon have a sedative effect, which may be mediated by benzodiazepine-type receptors, and also an antidepressant effect where noradrenergic and serotoninergic mechanisms will probably play a role.   Key words: Antidepressant, anxiolytic, Citrus limon, ethanolic extract, sedative.