Anxiolytic and nootropic activity of Vetiveria zizanioides roots in mice

BACKGROUND: Vetiveria zizanioides (VZ) (family: Poaceae), an aromatic plant commonly known as “Vetiver” has been used for various ailments. Concerning the various ailments being listed as the traditional uses of VZ, no mention about anxiety and memory was found. OBJECTIVE: The present study examined the anxiolytic and memory enhancing activity of ethanolic extract of V. zizanioides (EEVZ) dried roots in mice. MATERIALS AND METHODS: Activity of EEVZ was assessed using models of anxiety (elevated plus-maze [EPM], light/dark test, hole board test, marble-burying test) and learning and memory (EPM, passive shock avoidance paradigm). RESULTS: EEVZ at doses of 100, 200, and 300 mg/kg b.w. illustrated significant anxiolytic activity indicated by increase in time spent and number of entries in open arm, time spent in lightened area, number of head poking and number marble buried when compared to that of diazepam (1 mg/kg b.w.), a reference standard. The same treatment showed a significant decrease in transfer latency to reach open arm, shock-free zone, and number of mistakes when compared to that of scopolamine (0.3 mg/kg b.w.). EEVZ in all the doses (100, 200, and 300 mg/kg b.w.) significantly decreased mortality in sodium nitrite (250 mg/kg b.w.) induced hypoxia and also significantly increases contraction induced by acetylcholine on rat ileum preparation. CONCLUSION: The result emanated in the present investigation revealed EEVZ possesses significant anxiolytic and nootropic activity by possibly interplaying with neurotransmitters implicated in anxiety and learning and memory.