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J. Venom. Anim. Toxins incl. Trop. Dis. Vol.9, No.2, p.367, 2003. Poster - ISSN 1678-9199. |
FURTADO, M.F.D.; ROCHA, M.M.T.; TRAVAGLIA-CARDOSO, S.R.
Laboratório de Herpetologia, Instituto Butantan, São Paulo, Brazil
The Laboratory of Herpetology maintains snakes in captivity to provide venom for scientific research and antivenom production. National reference venoms (Bothrops jararaca and Crotalus durissus terrificus, the latter from the state of São Paulo) are used in the titration of their respective antivenoms produced nationwide. Antigens are also prepared for the immunization of horses in antivenom production. Venom milked from healthy snakes is collected in an ice bath then centrifuged at 1300g for 30 min at 4ºC and the supernatant is frozen at -20ºC. The venoms are subsequently thawed, homogenized and aliquoted in flasks for lyophilization. Annual batches are prepared using the largest number of extractions possible in order to provide greater homogeneity of the final product for each species. In 2001 venom batches were produced for Micrurus corallinus, M.frontalis, Lachesis muta, Bothrops alternatus, B.atrox, B.jararaca, B.jararacussu, B.leucurus, B.neuwiedi, B.moojeni, Crotalus durissus ssp, C.d.terrificus, C.d.collilineatus, B.jararaca reference batch 05 and a bothropic pool. The pH of the venom varied from 6.2 to 6.4 for the genus Crotalus and from 5.3 to 5.7 for the other species. The variation in the protein content of the venom in natura (mg of protein/ml of venom) was significant (P<0.001) among the species analyzed, with M.corallinus showing the highest protein concentration (367mg/ml of venom). The protein content varied from 838.3 µg/mg of venom (B. jararacussu) to 1381.7 µg/mg of venom (M. corallinus). The LD50 varied from 0.05mg/Kg (C. durissus) to 9.88mg/Kg (L. muta). The SDS-PAGE electrophoretic profiles showed bands between 67 to 14kDa to 67kDa for Bothrops, and 12-67 kDa for L.muta, a band of 32kDa and others more intense bands below 12.2kDa for Crotalus and two weak bands between and 43kDa and 69 kDa for Micrurus, with others more intense bands below 14.4kDa. The procedures and preliminary tests described above have been incorporated into our routine of each batch of venom produced.
CORRESPONDENCE TO:
M. F. D. FURTADO, Laboratório de Herpetologia, Instituto Butantan, São Paulo, 05503-900, SP, Brazil, Email: fatimabut@lycos.com