Effect of Butea monosperma on Memory and Behaviour Mediated via Monoamine Neurotransmitters in Laboratory Animals

Objective: To identify the fraction responsible for the nootropic activity of Butea monosperma and to correlate nootropic activity with monoamine and acetyl choline mediated behaviour. Materials and methods: The acetone soluble part of petroleum ether and ethanolic extracts of dried flowers of Butea monosperma exhibited nootropic activity in the elevated plus maze paradigm and active avoidance learning. The effect of active fraction was observed on clonidine-induced hypothermia (noradrenaline mediated behaviour), haloperidol-induced catalepsy (dopamine mediated behaviour), lithium-induced head twitches (serotonin mediated behaviour) and sodium nitrate induce respiratory arrest (acetylcholine mediated behaviour). Results: The elevated plus maze paradigm indicated that the nootropic activity resides in the ethyl acetate (PEF) fraction of petroleum ether extract and ethyl acetate fraction (AEF) and methanolic fraction (AMF) of alcoholic extract. These fractions reversed scopolamine-induced amnesia in mice. The fractions influenced the monoamine-mediated behavior differentially. The approximate LD50 of PEF, AEF and AMF were estimated as 0.3g/kg, >5.0g/kg and 3g/kg i.p. respectively. Conclusion: The PEF, AEF and AMF exhibited significant nootropic activity had differential effect on the monoamine mediated behaviour indicating different modes of their nootropic activity. These fractions need to be investigated further to understand mechanism of their action.