Neurotoxic effects of three fractions isolated from Tityus serrulatus scorpion venom

ABSTRACT

Scorpion venoms contain low molecular weight basic polypeptides, neurotoxins, that are the principal toxicagents. These toxins act on ion channels, promoting a derangement that may result in an abnormal release of neurotransmitters.In the present study we investigated some of the effects of the F, H and J fractions isolated from Tityus serrulatusscorpion venom on the central nervous system of rodents. The venom was partially purified by gel filtration chromatography.The neurotoxic effect of these fractions was studied on convulsive activity after intravenous injection, and on electrographicactivity and neuronal integrity of rat hippocampus when injected directly into this brain area. The results showedthat intravenous injection of the F and H fractions induced convulsions, and intrahippocampal injection caused electrographicseizures in rats and neuronal damage in specific hippocampal areas. Fraction J injected intravenously reduced thegeneral activity of mice in the open field but induced no changes when injected into the brain. These results suggest thatscorpion toxins are able to act directly on the central nervous system promoting behavioural, electrographic and histologicalmodifications.