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 toxic agents. 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 serrulatus scorpion 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 electrographic activity and neuronal integrity of rat hippocampus when injected directly into this brain area. The results showed that intravenous injection of the F and H fractions induced convulsions, and intrahippocampal injection caused electrographic seizures in rats and neuronal damage in specific hippocampal areas. Fraction J injected intravenously reduced the general activity of mice in the open field but induced no changes when injected into the brain. These results suggest that scorpion toxins are able to act directly on the central nervous system promoting behavioural, electrographic and histological modifications.

Developmental and sex differences in tetramethylenedisulfotetramine (TMDT)‐induced syndrome in rats

“…Interestingly, we did not observe barrel rotations previously in adult mice as part of TMDT‐induced seizure syndrome (Shakarjian et al, ). In rats, barrel rotations typically represent a hallmark of hypoglycemia‐associated convulsions but occur also following application of quinolinic acid, scorpion venom poisoning or intracerebroventricular administration of neuropeptides (somatostatin, vasopressin, endothelin‐1) and are considered a severe seizure behavior (Gastaut et al, ; Marrannes and Wauquier, ; Chew et al, ; Nencioni et al, ; Velísek et al, ). Regional brain glucose utilization studies suggest that barrel rotations mainly involve brainstem structures, that is, inferior colliculus, pontine nuclei, and vestibulo‐cerebellar pathways (Chew et al, ; Doriat et al, ; Wurpel et al, ).…”

“…following application of quinolinic acid, scorpion venom poisoning or intracerebroventricular administration of neuropeptides (somatostatin, vasopressin, endothelin-1) and are considered a severe seizure behavior (Gastaut et al, 1968;Marrannes and Wauquier, 1988;Chew et al, 1994;Nencioni et al, 2000;Vel ısek et al, 2008). Regional brain glucose utilization studies suggest that barrel rotations mainly involve brainstem structures, that is, inferior colliculus, pontine nuclei, and vestibulo-cerebellar pathways (Chew et al, 1994(Chew et al, , 1995Doriat et al, 1998;Wurpel et al, 1988).…”