Hydroalcoholic extract and fractions of Davilla rugosa Poiret: effects on spontaneous motor activity and elevated plus-maze behavior

Davilla rugosa Poiret is commonly used in Brazilian folk medicine. The use as stimulant induced us to study the effects on motor activity and anxiety using an open-field and an elevated plus-maze, respectively. The hydroalcoholic extract of the stems (HE) was fractionated with chloroform (CF), chloroform/ethyl acetate (CAF), ethyl acetate (AF), ethyl acetate/ethanol (AEF), ethanol (EF) and ethanol/water (EWF). Rats were treated orally with HE (7.5, 15, 30 or 60 mg/kg) or fractions (15 mg/kg). In the open-field, HE (15 mg/kg), AEF, EF and EWF increased locomotion frequency and decreased immobility time; the contrary was observed with 30 and 60 mg/kg of HE. These doses also increased defecation. No effects were observed with 7.5 mg/kg of HE, CF, CAF or AF, except for an increase in defecation induced by AF. In the elevated plus-maze, total entries and number of entries into the open and closed arms and the time spent in the open arms and its percentage were increased only with 15 mg/kg of HE. The open-field results suggest that the drug increases motor activity (stimulant effect) and that the active components are in the three more polar fractions. An anxiolytic effect was observed only with the HE.