%0 Journal Article
%T Convulsive and Neurodegenerative Effects in Rats of Some Isolated Toxins from the Tityus bahiensis Scorpion Venom
%A Luciene Toshie Takeishi Ossanai
%A Geane Antiques Louren£¿o
%A Ivo Lebrun
%A Ana Leonor Abrah£¿o Nencioni
%A Valquiria Abr£¿o Coronado Dorce
%J Journal of Toxins
%D 2013
%I Hindawi Publishing Corporation
%R 10.1155/2013/501876
%X Despite Tityus bahiensis being one of the most dangerous scorpions in Brazil, there are few studies about the effects of its venom, which acts mainly on the central nervous system. Previous studies demonstrated the convulsive ability of this venom. The present work aimed to study the hippocampal effects in rats of some toxins isolated from pool V, which induces a pronounced epileptogenic effect. The pool was separated by reverse-phase HPLC, and the peaks with higher yield (Tb V-1, V-5, V-24, V-27, and V-28) were used in the experiments. Cannulae and electrodes were implanted in the hippocampus of male Wistar rats (240¨C250£¿g). The animals were divided into six groups that received intracerebral injection of toxin solution (1 or 2£¿¦Ìg/¦ÌL) or Ringer solution (control group), and they were submitted to behavioral, electrographic, and histological analysis. All toxins studied evoked electrographic and behavioral epileptic-like activity to different degrees. Moreover, the toxins V-1, V-24, and V-28 caused significant neuronal loss in CA4 ipsi- and contralateral hippocampal areas. These results suggest that toxins from T. bahiensis scorpion, when injected into the hippocampus, are able to act directly on the central nervous system inducing convulsive and neurodegenerative effects. 1. Introduction From an epidemiological viewpoint, the scorpion family Buthidae is considered to be the most important among the 19 families distributed in the world [1]. Twenty-five species dangerous to humans belong to this family. In Brazil, scorpions from the genus Tityus, which belong to this family, represent about 60% of the neotropical fauna [2], and the most important species are Tityus serrulatus, T. bahiensis, T. stigmurus, and T. obscurus [3]. The purification and sequencing of toxin from T. bahiensis were initially done by Becerril et al. [4], who compared them with toxins from T. serrulatus and observed that the most abundant peptide from this scorpion (named ¦Ã-bahiensis) is 95% identical to toxin ¦Ã from the venom of Tityus serrulatus. Other toxins have already been isolated, such as III-8 bahiensis (III-8b), TbTx-VI, and IV-5 bahiensis (IV-5b), which show 80% homology with toxin IV-5 from T. serrulatus [5]. Meanwhile, there are few papers focusing on the purification, sequencing, mechanisms of action, and effects of toxins that comprise this venom [4¨C7]. In spite of the large number of studies in the literature as revised by Cologna et al. [3], the central effects of toxins and venoms have been neglected due to the common understanding that these peptides do not cross
%U http://www.hindawi.com/journals/jtox/2013/501876/