A Comparative Nootropic Activity of Crinum asiaticum and Crinum defixum in Animal Models

Abstract

The current study examined the nootropic activity of ethanolic extracts of Crinum asiaticum (EECA) and Crinum defixum (EECD). The effects of the extracts on rodents’ by using Elevated Plus Maze (EPM), scopolamine-induced amnesia (SIA), diazepam-induced amnesia (DIA), clonidine-induced (NA-mediated) hypothermia (CIH), lithium-induced (5-HT mediated) head twitches (LIH) and haloperidol-induced (DA- mediated) catalepsy (HIC) models. Piracetam was used as the standard drug. A significant increase in inflexion ratio (IR) was recorded in EPM, SIA and DIA models. A significant reversal effect was observed on rectal temperature in CIH model, reduction of head twitches in LIH models. However, no significant reduction in catalepsy scores in HIC models were observed with test extracts and standard piracetam. The results indicate that nootropic activity observed with EECA and EECD could be through improved learning and memory either by augmenting the noradrenaline (NA) transmission or by interfering with 5-hydroxytryptamine (5-HT) release. Further, the extracts neither facilitated nor blocked release of the dopamine (DA). Thus EECA and EECD elicited significant nootropic effect in mice and rats by interacting with cholinergic, GABAergic, adrenergic and serotonergic systems. Phytoconstituents like flavonoids had been reported for their nootropic effect and these are present in both ethanolic extracts of Crinum asiaticum (EECA) and Crinum defixum (EECD) and these active principles may be responsible for nootropic activity.