Cardiovascular Effects of Snake Venoms

The Papuan black snake (Pseudechis papuanus). Photograph by David Williams.

Papua New Guinean (PNG) and Australian snakes produce a wide range of toxins that affect different organ systems. Besides the neurological effects and toxic potential on various muscles and the blood-clotting cascade, snake venoms are also known to affect the cardiovascular system. Patients bitten by PNG snakes occasionally collapse early and show cardiac rhythmic disturbances that may be due to direct cardiotoxic effects. In addition, other threatening cardiovascular events such as extreme lowering or raising of heart rate or blood pressure have been observed after PNG snake bites, underlining the cardiotoxic potential of PNG snake venoms. Australian brownsnake envenomations, in particular by the Eastern brownsnake, Pseudonaja textilis, have also been associated with cardiovascular collapse which is poorly understood.

We are especially interested in the cardiovascular pharmacology of Papuan blacksnake (Pseudechis papuanus), coastal taipan (Oxyuranus scutellatus) and PNG small-eyed snake (Micropechis ikaheka) venoms, as well as in Australian brownsnake (Pseudonaja spp.) venoms. Our research aims to elucidate the mechanism(s) of cardiotoxicity and adverse cardiovascular sequelae using isolated cardiovascular tissues in vitro and integrated haemodynamic preparations in vivo. The efficacy of specific antivenoms will be assessed against cardiovascular responses to the snake venoms under investigation. In doing so, further insights into the action of these venoms will be gleaned, providing avenues for novel drug discovery, as well as improvement in the treatment of envenomation. This research is in collaboration with the Cardiovascular Therapeutics Unit (