Anxiolytic-like effect of chronic treatment with Erythrina velutina extract in the elevated plus-maze test.
BACKGROUND
In Brazil, Erythrina velutina (Fabaceae) is widely used as a tranquilizer and/or sedative, and its extract exerts an anxiolytic-like effect profile in animal models, although these results may be caused by its sedative or amnesic effects. AIMS, MATERIALS AND METHODS: Thus, this study evaluated the effect of acute and chronic (23-26 days) administrations of the hydroalcoholic extract of the stem bark of Erythrina velutina (orally) in mice submitted to the following tests: elevated plus-maze, forced swim, spontaneous locomotor activity, and habituation to active chamber. Chlordiazepoxide and imipramine were used as standard drugs.


RESULTS
In the elevated plus-maze test, chronic, but not acute, Erythrina velutina (100mg/kg) administration increased the percentage of open arm entries, an effect also seen in both acute and chronic treatments with chlordiazepoxide (7.5mg/kg). In the forced swim test, only imipramine (25mg/kg) decreased immobility time. Impairment of habituation was seen only with acute imipramine administration and with the lowest doses of Erythrina velutina extract tested in acute (10mg/kg) and chronic (50mg/kg) administrations.


CONCLUSIONS
These results suggest that chronic administration of the hydroalcoholic extract of the stem bark of Erythrina velutina exerts an anxiolytic-like effect on mice, and it could serve as a new approach for the treatment anxiety, although it may have an amnesic effect at low doses.
Laboratório de Fisiologia e Farmacologia do Sistema Nervoso Central, Departamento de Farmacologia, Setor de Ciências Biológicas, Universidade Federal do Paraná, Centro Politécnico, PO Box 19031, 81531-990, Curitiba, PR, Brazil.
I M
IM
Raupp
A
A
Sereniki
S
S
Virtuoso
C
C
Ghislandi
E L
EL
Cavalcanti E Silva
H A
HA
Trebien
O G
OG
Miguel
R
R
Andreatini
D000284:Administration, Oral; D000818:Animals; D014151:Anti-Anxiety Agents / Q000008:administration & dosage / Q000302:isolation & purification / Q000494:pharmacology*; D001007:Anxiety / Q000188:drug therapy*; D001522:Behavior, Animal / Q000187:drug effects; D001938:Brazil; D002707:Chlordiazepoxide / Q000494:pharmacology; D004195:Disease Models, Animal; D004334:Drug Administration Schedule; D004895:Erythrina / Q000737:chemistry*; D007099:Imipramine / Q000494:pharmacology; D008297:Male; D018782:Maze Learning / Q000187:drug effects; D008519:Medicine, Traditional; D051379:Mice; D009043:Motor Activity / Q000187:drug effects; D024301:Plant Bark; D010936:Plant Extracts / Q000008:administration & dosage / Q000494:pharmacology*; D013550:Swimming
D014151:Anti-Anxiety Agents; D010936:Plant Extracts; D002707:Chlordiazepoxide; D007099:Imipramine