Mohamed A Atef
National Antivenom &Vaccine Production Center, Saudi Arabia
Title: Endotheline Receptor Blocker, A Selective And More Potent Antagonist For Atractaspis Envenomation Than The Specific Antivenom
Biography
Biography: Mohamed A Atef
Abstract
Preparation of an antivenom against Atractaspis was a very lengthy and expensive process. In this study, an alternative treatment was tested using: 1-Nitroglycerin to antagonize the coronary vasospasm induced by the venom, 2- Bosentan to block the endothelin receptors, since there is a similarity in structure and effect between the toxic fraction of the venom (Sarafotoxins) and endothelins and 3- The specific Antivenom in comparison to nitroglycerin and bosentan. Pretreatment of rabbits with nitroglycerin, antivenom or bosentan completely protected all rabbits from the minimal lethal doses of venom or its toxic fraction. On the other hand, injecting any of the three drugs a few minutes after injecting one minimal lethal dose (MLD) of the venom or the toxic fraction and at the first signs of ischemia, just before death, showed that bosentan completely saved all rabbits. In case of nitroglycerin all rabbits died and in case of antivenom, only 5 rabbits were rescued. It is clear that bosentan is superior to the specific antivenom in protecting rabbits; this may be due to its higher affinity to endothelin receptors than sarafotoxins. This preclinical study shows a good potential in using bosentan as a selective antidote for atractaspis envenomation, especially in the African continent.
