Neuropharmacological effects of an ethanol extract of the Magnolia dealbata Zucc. leaves in mice.

Magnolia dealbata Zucc. is considered to have tranquilizer and anticonvulsant properties in Mexican traditional medicine. In the present study we report the effects of a crude extract of Magnolia dealbata (30, 100 and 300 mg/kg) on mouse central nervous system (CNS). Pharmacological effects were tested on ambulatory activity, anti-anxiety response, sodium pentobarbital-induced hypnosis and pentylenetetrazole (PTZ)-induced seizures in comparison to honokiol, buspirone, ethosuximide and diazepam as corresponding reference drugs. No changes in spontaneous locomotor activity were produced posterior to Magnolia dealbata administration; however, a significant and dose-dependent diminution in the anxiety response was observed in experimental models such as plus-maze, head-dipping and exploratory rearing tests. Magnolia dealbata not only prolonged the time of sodium pentobarbital-induced hypnosis and delayed the onset of PTZ-induced mioclonus and clonus, but also hindered the presence of tonic seizures and avoided mortality. The hypnotic, anxiolytic and anticonvulsant effects obtained in these experiments support the hypothesis that Magnolia dealbata possesses CNS activity and reinforces the popular use in Mexican traditional medicine.