RESUMO
Phospholipase A2 inhibitors (PLIs) are glycoproteins secreted by snake liver into the circulating blood aiming the self-protection against toxic venom phospholipases A2. In the present study, we describe the first complete nucleotide sequence of a bPLI from venom glands of a NewWorld snake, Lachesis muta. The deduced primary structure was compared to other known bPLIs and recent literature findings of other possible roles of PLIs in snakesare discussed.
Assuntos
Lachesis muta/classificação , Lachesis muta/intoxicação , /antagonistas & inibidores , Serpentes/classificação , Serpentes/fisiologia , Venenos de Serpentes/síntese química , Venenos de Serpentes/toxicidade , /análiseRESUMO
A comparative study was performed on the pharmacology and biochemistry of venoms from three subspecies of Lachesis muta (L. m. stenophrys, L. m. muta and L. m. rhombeata) from Brazil, Colombia and Costa Rica. All venoms induced lethal, hemorrhagic, edema-forming, myotoxic, coagulant and defibrinating effects, showing also proteolytic and indirect hemolytic activities. The venoms of L. m. stenophrys from Costa Rica and L. m. muta from Cascalheira, Brazil, had the highest lethal and hemorrhagic activities and the venom of L. m. rhombeata showed the highest coagulant activity, whereas no significant differences were observed in myotoxic and edema-forming activities at most of the time intervals studied. In addition, venoms showed similar electrophoretic patterns on SDSpolyacrylamide gel electrophoresis. In conclusion, despite quantitative differences in toxic and enzymatic activities, together with subtle variations in electrophoretic patterns, our results indicate that experimental envenomation by these venoms induce a qualitatively similar pathophysiological profile.