BOTHROPS SP. SNAKE-VENOMS - COMPARISON OF SOME BIOCHEMICAL AND PHYSICOCHEMICAL PROPERTIES AND INTERFERENCE IN PLATELET FUNCTIONS

Procoagulant, proteolytic, phospholipase and platelet pro-aggregating and inhibiting activities were screened for pooled venoms of seven Bot hrops species as well as Crotalus durissus terrificus and Lachesis mut a snakes typical of the Brazilian territory. As reported by other auth ors, we also found that examination of the electrophoretic and gel fil tration patterns of Bothrops snakes venoms could not be used for ident ification of the species of a given venom because of the lack of marke d interspecific differences within the same genus. Our data indicated that B. cotiara, B. alternatus and B. atrox possess no platelet pro-ag gregating activity, low inhibitory effect on platelet aggregation and very low or intermediate levels for the other activities. B. moojeni, B. neuwiedi and B. jararacussu whose venoms possess high procoagulant, platelet pro-aggregating and phospholipase activities are low in both proteolytic and platelet inhibitory activities. B, jararaca venom sho wed the highest inhibitory effect on platelet aggregation and very low platelet pro-aggregating activity. Compared with the Bothrops venoms studied, L. muta venom showed that highest proteolytic activity while C. d. terrificus venom presented remarkable high platelet pro-aggregat ing and phospholipase activities. In all venoms, proteolytic activity could be completely inhibited by EDTA (2 mM) alone. In contrast, the p resence of phenylmethylsulfonyl fluoride (5 mM) inhibited partially th e caseinolytic activity of all venoms, except that L. muta venom, whic h was almost completely blocked by this reagent. Altogether, these dat a confirm the presence of high levels of metalloproteinases in the ven oms of Crotalinae snakes. Most of these enzymes are dependent of the a vailability of Ca2+, being much less the same concerning the presence of serine residues in their active sites. The data indicated that the presence and levels of procoagulant, azocaseinolytic and phospholipase A(2) activities alone could not differentiated the species of the Bot hrops venoms studied, particularly in the cases of B. jararaca, B. moo jeni and B. atrox. However, the platelet inhibiting property of low do ses of B, jararaca venom can be useful to differentiate it from B. moo jeni venom. In the same way, the platelet pro-aggregating activity of high doses of B. jararaca venom may be used to distinguish it from B. atl ox crude venom, otherwise very similar but incapable to activate p latelets. In conclusion, our comparative screening of biological prope rties has indicated that platelet studies may serve as a tool to disti nguish among venoms that otherwise behave biochemically in a very simi lar way. Although promising, the general applicability of platelet act ivation studies by snake venoms for classification or taxanomical purp oses has yet to be extended to other family of snakes to be proven use ful. (C) 1998 Elsevier Science Inc.