L [Anacardiaceae] is a plant used by traditional medical practitioners in Nigeria in the treatment of various nervous disorders. In this study, the anxiolytic properties of the aqueous, methanol and ethanol extracts of the leaves were examined using aggressive-behaviour response and depression-related swimming behaviour activities. All the extracts administered orally were not toxic to mice up to a dose of 5 g/kg. On intraperitoneal injection, however, the LD50
values [mice/rats] were calculated to be 0.48 g/kg / 0.62 g/kg for ethanol extract, 1.10 g/kg / 1.08 g/kg for methanol extract and 1.36 g/kg / 1.42 g/kg for aqueous extract respectively. All residues from different extractions were dissolved in normal saline and administered intraperitoneally. It was found that the three extracts abolished the aggressive attacks by rats, and reduced swimming time in mice. These effects were found to be most potent with the administration of the ethanol extract. These effects of the extracts were blocked by flumazenil, an antagonist of GABAA
receptor. The results suggest that the extracts of Spondias mombin
possess anxiolytic effect mediated by GABAergic transmission.