The venom of Bothrops asper from Guatemala: toxic activities and neutralization by antivenoms

Bothrops asper is responsible for approximately half of the snakebite enven omations in Central America. Despite its medical relevance, only the venom of Costa Rican populations of this species has been studied to some detail, and there is very little information on intraspecies variability in venom composition and toxicity. Venom of B. asper from Guatemala was analyzed by sodium dodecyl sulphate-polyacrylamide gel electrophoresis and two-dimensio nal gel electrophoresis, and its basic pharmacological activities were inve stigated with standard laboratory assays. Venom has lethal, hemorrhagic, my otoxic, edema-forming, coagulant, defibrinating and phospholipase A(2) acti vities, showing a similar toxicological profile to the one previously descr ibed for B. asper from Costa Rica. In addition, polyvalent antivenoms produ ced in Mexico and Costa Rica, and currently used in Guatemala, were tested for their ability to neutralize venom's toxic activities. Both antivenoms w ere effective against all effects studied, although the Costa Rican product showed higher potency against most activities tested and higher antibody t iter against venom components, as determined by enzyme immunoassay. It is s uggested that different dosage regimes should be considered when using thes e antivenoms in B. asper envenomations in Guatemala. (C) 2000 Elsevier Scie nce Ltd. All rights reserved.