Reptile venom is complex mixtures of biological compounds that act on nerve cells to block electrical signals, and on blood vessels to cause bleeding. They are secreted by venom glands and delivered through spurs, stingers or fangs to kill or digest prey or defend the snake.
도마뱀분양Venoms vary in their toxicity. Hemotoxic venom can cause bleeding at the bite site and all body openings, while neurotoxic venom can cause blindness and paralysis.
What is Venom?
Venom is a poisonous liquid that reptiles produce to kill or incapacitate prey and attackers. It is delivered into prey or attackers through specialized glands and ducts that protrude from their mouths or fangs. Venom contains several chemicals that are highly toxic to human beings.
Snake venom includes two broad classes of toxins: neurotoxic and hemotoxic. Neurotoxic venoms are typically found in elapid snakes such as cobras, while hemotoxic venom is more common in viper species. 도마뱀분양
Hemotoxic venoms cause blood loss by damaging and dissolving the walls of capillary vessels, which leads to internal bleeding. They also block the body’s ability to form blood clots. Hemotoxic venom is the primary weapon of rattlesnakes and other pit vipers.
A small amount of proteolytic venom is also present in most venomous snakes. This venom breaks down proteins within cells, thus destabilizing them and causing cell death. It is most commonly used in preying on ectothermic (cold-blooded) prey such as lizards and other snakes.
The venom of the black mamba is the fastest-acting of all animal venoms. It can kill a human in less than 30 minutes. The venom of the black mamba also contains an acid that destroys the protective mucous membrane, which is why this snake is so deadly.
How is Veno 도마뱀분양 m Produced?
The venom glands of snakes are a product of evolution. They have evolved twice: first in helodermatid lizards and then in advanced snakes belonging to colubroids, viperids and elapids. Venom is considered to be a varied form of saliva excreted through specialised parotid salivary glands, situated on each side of the head behind the eyes, after which it is delivered through tubular fangs (specialised hollow teeth). This venom acts as a means of killing or incapacitating prey species and is used by snakes for their protection as well as as a hunting strategy.
Ninety percent of venom is proteins by dry weight, most of which are enzymes. Different venoms contain different combinations of enzymes, with some causing much deadlier effects than others. The enzymes in venom act in tandem to paralyze prey and initiate digestion.
Venom production is a highly complex process. It is regulated by a number of factors including genes, their expression, translation and post translational modification. It has also been observed that mutations in certain genes may have a direct impact on the formation of venom phenotypes.
The venom of snakes contains a large number of proteolytic, phospholipase and hyaluronidase-type enzymes. These act as a launching pad to attack prey on the molecular level and disrupt the cell’s structural integrity. They also inhibit the activity of vital organs and cause internal bleeding.
What Are the Toxins in Venom?
A snake’s venom is a complex brew of dozens of compounds. They include neurotoxins that disable the nervous system in their prey and cause them to suffocate, haemotoxins that affect the circulatory system by breaking down blood-clotting compounds and causing uncontrolled bleeding, and myotoxins that paralyse the muscles.
Venom composition changes within a species according to age, gender, diet and geographic location. For example, the venom of Russell’s viper (Daboia russelii), which attacks urban populations, has more hemotoxins than other species due to its lifestyle and diet, and its bite is responsible for more deaths in India than any other snake species, with the exception of saw-scaled vipers (Echis carinatus).
The chemicals found in snake venom are exceptionally well-designed: they bind to specific biological targets with high affinity and selectivity. This makes them valuable drug candidates, and some of the toxins have already been modified to make safer, more effective drugs.
For example, crotamine, a myotoxin isolated from the venom of tropical South American rattlesnake Crotalus durissus terrificus, can be used to treat venomous snakebite. The molecule has been modified to increase its stability, so it can be injected orally, which is important for treating patients. Defensins, small proteins that act as host defence peptides, are also present in viperid venom. They bind to channels in plasma membranes including those of muscle cells, where they accumulate in lysosomes to cause analgesic, myotoxic and cytotoxic effects. The structure of one such defensin, RVV-X, has been elucidated.
What Are the Symptoms of Venom Poisoning?
If a snake is venomous, a bite will likely cause pain and swelling. But the symptoms will depend on the type of venom involved and where the snake bit. Snake venoms contain cytotoxins that damage tissue around the bite, hemotoxins that cause bleeding and may even prevent blood clotting, cardiotoxins that affect the heart, and neurotoxins that affect the nervous system.
Snakes with hemotoxic venom can kill in as little as 30 minutes if the person is not treated quickly. Hemotoxic venom from snakes such as copperheads (Pyrophis cingulatus), saw-scaled vipers (Echis carinatus), and Indian russel’s vipers (Daboia russelli) attacks the red blood cells in the body, which causes massive internal bleeding and severe pain.
Neurotoxic snake venom can cause paralysis that will not stop, if it is not treated, within a few hours. This venom attacks the nerves, including the muscles used to breathe. If untreated, respiratory muscle paralysis can lead to death.
When a venomous snake bites, it injects the poison into the victim’s body using a modified salivary gland. The venom can affect the whole body or just a specific area. Snakebites occur worldwide, but most envenomings are seen in Africa, Asia and Latin America where snake populations are the largest and medical care is weakest.