Convulsant activity and neurochemical alterations induced by a fraction obtained from fruit Averrhoa carambola (Oxalidaceae: Geraniales)

We obtained a neurotoxic fraction (AcTx) from star fruit ( Averrhoa carambola) and studied its effects on GABAergic and glutamatergic transmission systems. AcTx had no effect on GABA/glutamate uptake or release, or on glutamate binding. However, it specifically inhibited GABA binding in a concentrat...

Full description

Saved in:
Bibliographic Details
Published in:Neurochemistry international 2005-06, Vol.46 (7), p.523-531
Main Authors: Carolino, Ruither O.G., Beleboni, Renê O., Pizzo, Andrea B., Vecchio, Flavio Del, Garcia-Cairasco, Norberto, Moyses-Neto, Miguel, Santos, Wagner F. dos, Coutinho-Netto, Joaquim
Format: Article
Language:English
Subjects:
Animals
Averrhoa carambola
Binding, Competitive
Biological and medical sciences
Brain - drug effects
Brain - metabolism
Brain - physiopathology
Brain Chemistry - drug effects
Brain Chemistry - physiology
Convulsant
Convulsants - isolation & purification
Convulsants - toxicity
Epilepsy - chemically induced
Epilepsy - metabolism
Epilepsy - physiopathology
Fruit - chemistry
Fundamental and applied biological sciences. Psychology
GABA/glutamate uptake, release and binding
gamma-Aminobutyric Acid - metabolism
Geraniales
Glutamic Acid - metabolism
Magnoliopsida - chemistry
Male
Mice
Molecular Weight
Neurons - drug effects
Neurons - metabolism
Neurotoxins - isolation & purification
Neurotoxins - toxicity
Oxalidaceae
Plant Extracts - chemistry
Plant Extracts - isolation & purification
Plant Extracts - toxicity
Presynaptic Terminals - drug effects
Presynaptic Terminals - metabolism
Radioligand Assay
Rats
Rats, Wistar
Synaptic Transmission - drug effects
Synaptic Transmission - physiology
Vertebrates: nervous system and sense organs
Video-electroencephalogram
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:We obtained a neurotoxic fraction (AcTx) from star fruit ( Averrhoa carambola) and studied its effects on GABAergic and glutamatergic transmission systems. AcTx had no effect on GABA/glutamate uptake or release, or on glutamate binding. However, it specifically inhibited GABA binding in a concentration-dependent manner (IC 50 = 0.89 μM). Video-electroencephalogram recordings demonstrated that following cortical administration of AcTx, animals showed behavioral changes, including tonic-clonic seizures, evolving into status epilepticus, accompanied by cortical epileptiform activity. Chemical characterization of AcTx showed that this compound is a nonproteic molecule with a molecular weight less than 500, differing from oxalic acid. This neurotoxic fraction of star fruit may be considered a new tool for neurochemical and neuroethological research.
ISSN:0197-0186
1872-9754
DOI:10.1016/j.neuint.2005.02.002