Estudo comparativo de efeitos inflamatórios locais induzidos por peçonhas botrópicas

Abstract

Bothropic envenomation is characterised by severe local damage caused by the toxic action of venom components and aggravated by induced inflammation. In this comparative study, the local inflammatory effects caused by the venoms of B. alternatus and B. moojeni, two snakes of epidemiological importance in Brazil, were investigated. The toxic action of venom components induced by bothropic venom was also characterised. Herein, the oedema, hyperalgesia and myotoxicity induced by bothropic venom were monitored for various lengths of time after venom injection in experimental animals. The intensity of the local effects caused by B. alternatus venom is relatively smaller than B. moojeni venom. Furthermore, the inflammatory reaction induced by B. moojeni venom is mediated by eicosanoid action, histamine and nitric oxide, with significant participation of bradykinin on the hyperalgesic and myotoxic effects of this venom. These mediators also contribute to inflammation caused by B. alternatus venom. However, the inefficient anti-inflammatory effects of some local modulation suggest that histamine, leukotrienes and nitric oxide have little role in the oedema or myonecrosis caused by B. alternatus venom. Our results indicate that metalloproteases and phospholipases A2 have a central role in the inflammatory reaction induced by bothropic venoms, but serine proteases also contribute to the local effects of B. moojeni venom.