Comparative study of Crotalus durissus terrificus snake venoms born in captivity in the Laboratory of Herpetology of Butantan Institute and the national crotalic reference venom
Description: Snakes of the genus Crotalus (Viperidae family) are very important from the epidemiological point of view, once, although they account only for about 9% of ophidian accidents, they are with the highest lethality (1.1%). In Brazil, the genus Crotalus is represented by a single species, Crotalus durissus (C.d.), which has a wide geographical distribution in Brazil and has 5 subspecies, C.d.marajoensis, C.d.ruruima, C.d.collillineatus, C.d.cascavella and C.d. terrificus, the latter being more legendary and widely dispersed in southern Brazil. Crotalic venom can cause neuro and myotoxicity. In addition, symptoms like systemic neurotoxicity accompanied by rhabdomyolysis result in tubular necrosis and renal failure, common in crotalic poisoning, thus constituting the leading cause of death. All these symptoms are mainly caused by crotoxin. Besides crotoxin, gyroxine, crotamine and convulxine are proteins found in significant amounts and variable in crotalic venom. The elucidation of these activities is important both for envenomation-related research and for the production of anti-crotalic sera, considering that, if present, variations may result in the production of less effective sera and inconsistent results in scientific research. In this context, although there is a search for standardization and stabilization of the different components of ophidian venoms, they still lack conclusive results in both aspects.It is clear the necessity of the use of reference venoms at the national level, as well as the standardization of the methods of testing the biological activities of the Brazilian venom of snakes to ensure a uniformity in antiofidic sera. Thus, from 1987, the National Institute of Quality Control in Health (INCQS) and the serum producers' Brazilian laboratories began to use the National Reference Crotalic Venom, in order to minimize interlaboratory differences in the determinations of potency of this antivenom. Consequently, the Butantan Institute became responsible for the preparation and distribution of National Reference Crotalic Venom. For the preparation of the reference venoms, the first extractions of snakes that have just arrived at the Butantan Institute are used. Since then, 02 batches of National Reference Crotalic Venom have been produced from the venom of the snake C. d. terrificus, whose potency was determined exclusively by INCQS, which is responsible for its storage and distribution.Considering the importance of elucidating the composition of both reference and venomous venoms, this study intends to compare the venom of the National Reference Snake Crotalus durissus terrificus with those of the snakes born and kept in captivity in the Laboratory of Herpetology of the Butantan Institute. It is important to emphasize the importance of this work, since, due to the reduction in the supply of these animals from the nature, there may be a scarcity of these animals for the production of the Crotalic Snake National Reference, thus the use of the venoms of the captive snakes would supply this demand. (AU)
Funding type: grant
Funder scheme: Auxílio à Pesquisa - Regular
Start date: 2017-05-01
End date: 2019-04-30
Investigator: Anita Mitico Tanaka-Azevedo
Institution: Instituto Butantan
Subfield: Toxicology
Domain: Life Sciences
Funded outputs count: 10
Funder award ID: 17/01890-0
OpenAlex ID: G6181707340