The article surveys the substances identified in plants reputed to neutrali
ze the effects of snake venoms. Protective activity of many of them against
the lethal action of the Venom of the jararaca (Bothrops jararaca) snake w
as confirmed by biological assays. It was shown that all belong to chemical
classes capable of interacting with macromolecular targets - receptors and
enzymes. In a few cases it has been shown that exogenous natural micromole
cules can mimic the biological activity of endogenous macromolecules. From
the evidence presented, it can be inferred that micromolecules which neutra
lize the action of snake Venoms mechanistically replace endogenous antitoxi
c serum proteins with Venom neutralizing capacity such as produced by some
animals. (C) 2000 Elsevier Science Ltd. All rights reserved.