[Study on the venoms of the principal venomous snakes from French Guiana and the neutralization].

We studied some biochemical, toxic and immunological characteristics of the venoms of Bothrops atrox, Bothrops brazili and Lachesis muta, Viperidae responsible for most of the bites of venomous snakes in French Guiana. Chromatographic (HPLC) and electrophoretical profiles (SDS-PAGE), lethal, hemorrhagic, defibrinogenating, coagulant, thrombin like, proteolytic, fibrino(geno)lytic and phospholipase activities were studied. In addition, the neutralization of some toxic activities conferred by four antivenins was compared. The chromatographic and electrophoretic profiles were different for the three venoms, showing differences between Bothrops and L. muta venoms. In general, bothropic venoms showed the highest toxic and enzymatic activities, while the venom of L. muta showed the lowest lethal, hemorrhagic and coagulant activities. The enzymes of bothropic venoms responsible for gelatinolytic activity were around 50-90 kDa. All the venoms were able to hydrolyze a and beta chains of the fibrinogen, showing different patterns of degradation. Although all the antivenoms tested were effective to various degrees in neutralizing the venom of B. brazili and B. atrox, neutralization of L. muta venom was significantly better achieved using the antivenom including this venom in its immunogenic mixture. For the neutralization of L. muta venom, homologous or polyvalent antivenoms that include the "bushmaster" venom in their immunogenic mixture should be preferred.