European Journal of Biomedical and Pharmaceutical Sciences

ANXIOLYTIC-LIKE EFFECT OF CRUDE METHANOL EXTRACT OF ERYTHROPHLEUM IVORENSE IN MICE

Wakeel O. K.*, Ayankunle A. A., Olapade M. K., Kolawole O. T. and Oyekale A. O.

ABSTRACT

Erythrophleum ivorenses A. Chev (Fabaceae) is a medicinal plant used in folk medicine in the management of pain, swollen condition, antiemetics and also in treatment of convulsive disorder. No existing data was found on the neurobehavioural properties; hence, we examined the modifications of behavioural indices evoked in mice by the introduction of methanol extract from stem bark of Erythrophleum ivorense under the conditions of four neurobehavioural tests. Using absolute methanol, the plant was macerated and the crude methanol extract (CME) was obtained. Intraperitoneal injections of CME at doses 5, 10, or 20 mg/kg and diazepam (1 mg/kg) or control (10ml/kg) were used; the effects observed were compared with the action of the control. In the hole-board test, injections of the CME significantly (p<0.05) increased in a dose-dependent manner in the manifestations of research behaviour (increased the number of head dips into openings) as compared with control. In open field test, CME significantly reduced rearing in a dose dependent manner while, grooming significantly (p<0.05) reduced at the maximum dose (20 mg/kg) as compared with controls. Administration of CME in dark and light experimental model greatly increased the time spent and the number of entrance of mice into light compartment. In elevated plus-maze CME treated mice exhibited significant increase (P < 0.05) in the number of open arm entries, time spent in open arm, but decrease in time spent in closed arm compared with control. In order to establish the mechanism involved in the neurobehavoural effect, flumazenil a receptor antagonist for GABA receptor was pretreated and the results indicated that flumazenil (2.0 mg/kg, i.p.) blocked the NIR inhibition induced by the methanol extract. The results obtained suggest that the methanol stem bark extract of E. ivorenses possesses neurobehavioural effect via GABAergic pathway and may account for its use in ethnomedicine.

Keywords: Erythrophleum ivorenses.