Oct. 12, 2010
Snake venoms are something of an evolutionary marvel. Through minute mutations and changes, normal saliva has changed to the myriad of harmful enzymes, toxins, non-peptide organic substituents, small peptides, and inorganic and metal ions found in the venom of today’s snakes. In general, venom is defined as a simple to complex secretion produced in a specialized gland that is typically delivered via specialized envenomation systems, including a secretory gland, (often but not always) specialized teeth, and a suite of specific behaviors allowing venom delivery. Within this report, the major enzymes, peptides, and non-organic material that contribute to the toxicity of venom will be discussed. Medicinal uses of venom in the treatments of cancer and blood diseases will be briefly discussed as well.
Each toxin is specifically formulated to complete the four major goals of venom, which are to immobilize, paralyze, digest, and kill prey items. This is achieved in several ways depending on the target of the venom in question. Venom constituents can be divided up into two categories, neurotoxic chemicals and hemotoxic chemicals. Neurotoxins disrupt and destroy the targets nervous system. These toxins do this by disrupting the sodium, potassium, and calcium ion channels in nerves, as well as antagonizing muscarinic and nicontinic receptors. Neurotoxins can be presynaptic or postsynaptic. Presynaptic neurotoxins affect a nerves ability to send chemical messeges, while postsynaptic toxins affect the places nerve signals are interpreted such as muscles and other nerves. Hemotoxic venom destroys tissues in different ways. Many hemotoxins cause problems such as cardiac arrest, kidney failure, edema, necrosis, and intense pain. These effects are cause by hemotoxins anticoagulation effects.
Enzymes are found commonly in both hemo-and neurotoxins, and enzymes play a crucial role in snake...