Biochemical and pharmacological characterization of a toxin isolated from Tityus serrulatus scorpion venom

Abstract

Scorpion venoms are composed mainly by toxins, low molecular weigh polypeptides with neurotoxic activity. Generally scorpion venom effects are attributed to the peripheral action of the toxins releasing neurotransmitters such as adrenaline, noradrenaline and acetylcholine. Nevertheless, it is known that the scorpion venoms act too on the central nervous system modifying the release of mediators. The aim of the present work is to investigate the IV-IV toxin, deriving from Tityus serntlatiis scorpion venom, which effect on the central nervous system is unknown. This toxin is eluted closed by TsTX, another toxin purified from the same venom, very well characterized and having convulsive and excitotoxic effects. N-terminal sequencing and molecular mass of the toxin will be realized to compare with TsTX as well as the electrographic recording and behavioral observation after intracerebral injection in rats, preceded or not by glutamate receptor antagonists. Histological analysis will confirm neuronal loss in the brain. The present work aims to study the central effects of a not characterized scorpion toxin, and besides to develop a useful tool in the study of the ionic channel functioning, epileptogenisis, and neurotransmitters release from central nervous system. (AU)