Abstract
INTRODUCTION: The stem bark of Maerua angolensis DC. (Capparaceae) is traditionally used for management of epilepsy. Our aim was to evaluate the antiseizure potential and identify possible mechanisms by which the effects are registered. METHODS: The petroleum ether/ethyl acetate extract (100-1000 mg kg(-1)) was administered per os to male Sprague-Dawley rats after pretreatment with flumazenil (0.3 mg kg(-1)) or L-arginine (150 mg kg(-1)) or sildenafil (5 mg kg(-1)) and they subsequently received a subcutaneous injection of pentylenetetrazole (65 mg kg(-1)). Rats were observed for latency to and duration of myoclonic seizures and additionally the level of protection against oxidant markers and products was assessed in vitro and in vivo. RESULTS: The extract (300 and 1000 mg kg(-1), p.o.) significantly delayed the onset and decreased the duration and frequency of PTZ-induced convulsions. The anticonvulsant effect of MAE (300 mg kg(-1), p.o.) was reversed by pretreatment with flumazenil, L-arginine, or sildenafil. Also, MAE (300 mg kg(-1)) treatment reversed significantly PTZ-induced oxidative stress in rat brain tissue. CONCLUSION: The petroleum ether/ethyl acetate fraction exhibits antiseizure activity by affecting GABAergic and nitric oxide-cGMP pathways. In addition, the extract protects against the generation of free radicals and the oxidative products of the PTZ-induced seizures.