Neurobehavioural evaluation of Lophira alata (Ochnaceae) stem bark extract in mice

Stem bark and leaves of Lophira alata (Family: Ochnaceae) have been used traditionally for their anti-psychotic, anti-convulsant and anxiolytic properties. Since no existing data was found on the neurobehavioural properties, this study was carried out to evaluate some neurobehavioural properties of the aqueous extract of the stem bark of L. alata in animal models.

The oral mean lethal dose (LD50) of the extract was estimated, and preliminary phytochemical screening was conducted. Lophira alata extract (200, 400 and 800 mg/kg, p.o.) was investigated for antidepressant effect using the forced swim and tail suspension tests, and the anxiolytic potential was assessed using the stair case and hole board tests. Pentylenetetrazole-induced convulsion test was used to investigate the anticonvulsant potential of the extract.

The LD50 was estimated to be >5000 mg/kg. Oral administration of L. alata extract produced a significant (p<0.05) non-dose-dependent decrease in the period of immobility in both the forced swim and tail suspension tests. While a significant decrease (p<0.05) in episodes of grooming was recorded in the staircase test, the number of head dips was not significantly reduced (p>0.05) in the hole board test. In the pentylenetetrazole-induced convulsion, a non-dose-dependent increase in onset of tonic-clonic seizures and protection from death was recorded.

The results obtained suggest that the aqueous stem bark extract of L. alata possesses neurobehavioural properties which may account for its use in ethnomedicine.