Neurotransmitter evaluation in the hippocampus of rats after intracerebral injection of TsTX scorpion toxin

• Published in: Journal of Venomous Animals and Toxins including Tropical Diseases
• Main Authors: ALA Nencioni, SA Barreto, I Lebrun, JC Florio, GA Lourenço, VAC Dorce
• Format: Article in Journal/Newspaper
• Language: English
• Published: SciELO 2009
• Subjects: scorpion toxin; microdialysis; hippocampus; neurotransmitters; neurodegeneration; riluzole; Arctic medicine. Tropical medicine; RC955-962; Toxicology. Poisons; RA1190-1270; Zoology; QL1-991; Arctic
• Online Access: https://doi.org/10.1590/S1678-91992009000200007; https://doaj.org/article/fd646f0896df40938e71b656d5ee5a3b

TsTX is an α-type sodium channel toxin that stimulates the discharge of neurotransmitters from neurons. In the present study we investigated which neurotransmitters are released in the hippocampus after TsTX injection and if they are responsible for electrographic or histopathological effects. Microdialysis revealed that the toxin increased glutamate extracellular levels in the hippocampus; however, levels of gamma-aminobutyric acid (GABA), glycine, 5-hydroxyindoleacetic acid (5-HIAA), homovanillic acid (HVA) and 3,4-dihydroxyphenylacetic acid (DOPAC) were not significantly altered. Neurodegeneration in pyramidal cells of hippocampus and electroencephalographic alterations caused by the toxin were blocked by pretreatment with riluzole, a glutamate release inhibitor. The present results suggest a specific activity of TsTX in the hippocampus which affects only glutamate release.