Evaluation of the central activity of the ethanolic extract of Acosmium subelegans (Mohlenbr) in mice

Abstract

The ethanolic extract (EE) of Acosmium subelegans (Mohlenbr) Yakovl (perobinha-do-campo) was tested to behavioral paradigms in mice to investigate its putative central depressant effect. Oral pretreatment with the EE significantly reduced in a dose-dependent way the locomotor activity and increased by 30-55% the barbiturate sleep duration relatively to control values. At the highest dose (1,0 g.kg -1 ) it decreased the extension time/flexion time ratio of the maximal electroshockinduced convulsions, enhanced the latency to the pentylenetetrazol-induced convulsions and diminished by 26% the number of seizures, indicating an anticonvulsant action. No changes were observed in the motor coordination, the core temperature, climbing behavior, catalepsy and the plus-maze performance. The preliminary results indicate that the EE of A. subelegans induce a CNS depressant effect, more specifically an anticonvulsant effect that deserve a thorough investigation.Acosmium subelegans (Mohlenbr) Yakovl, Leguminaceae, popularly known as "perobinha-do-campo", is used in the Brazilian folk medicine as sedative or "tranquilizer", in epilepsy treatmenr, in hysteria, nervous breakdown and chorea 1 . Previous pharmacological studies described that the benzenic extracts obtained from the related species Acosmium dasycarpum (Vog) Yakovl produced a depressant effect upon the central nervous system (CNS) of rats and mice, revealed by a potentiation of barbiturate-sleep, a reduction of the spontaneous and the amphetamine-induced locomotor activity. No protection against pentylenetetrazol and stricnine-induced convulsions was seen 2 . The extract main active constituent was identified as lupeol, a triterpene compound. Lupeol, also reduced the ambulation of mice and potentiated the barbiturate-hypnosis without affecting the animals motor coordination 3 . Comparatively, the ethanolic extract of A. subelegans presented a similar profile of action, decreasing the locomotion in rats 4 and potentiating the barbiturate-induced sleep in mice 5 . The present

Constituintes da casca externa de plantas do cerrado e suas atividades biológicas

“…Atualmente é vendido o fitoterápico Ritmoneuran® que inclui em sua fórmula extrato de L. elegans, presente também no medicamento Vagostesyl. Pesquisas feitas para comprovar a eficácia e toxicidade da planta nesses medicamentos mostram o efeito de extratos etanólicos da casca na inibição do Sistema Nervoso Central e anticonvulsionante em ratos (Vieira et al 2002b), atividade atribuída ao triterpeno lupeol. Foi descrito um alcaloide e seu enantiômero do extrato da casca de L. elegans, a sweetinina e homo-sweetininia (Balandrin & Kinghorn 1981), além de isolada uma pirona da casca de raiz (Oliveira et al 1994).…”