Spider bites and venoms
the male persuasion, have been investigatingways to reverse problems with gaining or maintaining erections for possibly thousands of years. It has only been recently though, that science has finally offered some help in the form of Viagra or Cialis. Unfortunately, such drugs often have negative side effects or sometimes they just do not work. For that reason, scientists continue to look for better options.Spider bites and venoms In this latest effort, the team in Korea has built on research conducted by another team working in Brazil back in 2011—they found that a toxin found in the wandering spider (which makes its home in Brazil) increased cavernosal relaxation in mice—cavernosum are sponge-like regions of erectile tissue found inside the penis. In order for an erection to occur, bodily chemicals must loosen valves that control blood flow, allowing for engorgement, so, this was good news.
Spider bites and venoms
Research into the possible use of wandering spider venom arose after a team in Brazil studied the impact of spider bites on the local population back in 2000. They found that among other symptoms, the spider bites sometimes resulted in priapism—erections that last an abnormally long time. Over time other researchers have isolated the chemical involved, PnTx2-6, and used recombinant DNA techniques to produce the protein in caterpillar cells. Now, testing by this latest team of researchers indicates that the protein helps restore erectile function in the tissue of rats. That is a long way from helping humans, of course, but thus far, the research appears promising.
No doubt research will continue with PnTx2-6, and likely other possibilities as well. As the population ages, more and more men find they experience some degree of ED. But it will take awhile—even if all goes well, it will be at least a couple of years before PnTx2-6 makes its way through clinical trials and into pharmacies.
Spider bites and venoms
Spider venoms are a cocktail of many chemicals spider bites and venoms .Some are neurotoxins, which evolved to kill or immobilise arthropods like insects by attacking their nervous systems; others are cytotoxins which help break down the tissue so the spider can ingest a liquefied meal.Spider bites and venoms Unfortunately, a few of these chemicals can be seriously toxic to people.
Spider bites and venoms
Venoms are chemicals of biological origin (i.e. made by an animal) used for the purpose of attack or defence . Venoms are made by specialised organs, such as modified salivary glands, and are delivered via specialised systems such grooved or hollow fangs. Most venoms consist of a complex mixture of chemical substances, including proteins, peptides, sugars and other substances.Spider bites and venoms Venoms may affect many systems of the body. Common venom effects include paralysis, interference with blood clotting, breakdown of muscle, pain, breakdown of tissues and effects on the cardiorespiratory system (the heart and lungs).
Spider bites and venoms
There are basically two types of venom that have an effect on humans: neurotoxic and cytotoxic (or necrotic) venoms. Neurotoxic venoms work directly on the nervous system. The best known example is the venom of the Black Widow/Redback spiders (Latrodectus species). Necrotic venoms cause damage to the tissues, such as blisters and lesions. There are no confirmed records of spider bites in Australia causing necrotic lesions, although the bites of Recluse Spiders, which are native to the Americas, have been confirmed to cause tissue necrosis. Generally, neurotoxic venoms kill more quickly than cytotoxic venoms.
Spider bites and venoms
The main effect of a neurotoxic venom is to block nerve impulses to the muscles, causing cramps and rigidity and also disrupting many of hte body’s functions. It also overstimulates the production of the neurotransmitters, acetylcholine and norephinephrine, causing paralysis of the entire nervous system. The combined effect causes sudden and severe stress to the entire human body. In extreme cases, this can result in death due to respiratory or circulatory failure. Funnel-web Spider venom – known as atraxotoxin – acts directly upon the nervous system in this way. 
Spider bites and venoms
Necrotic venoms cause skin blisters around the site of the bite, which may lead to ulcers and tissue death – necrosis. Recent studies of confirmed spider bites suggest that, in Australia, these bites do not cause tissue necrosis. These sorts of symptoms are most likely due to other types of clinical conditions.
Spider bites and venoms
Antivenoms for spider toxins are produced by injecting horses, goats or rabbits with the spiders’ venom. This doesn’t harm these animals because they are either given only small venom doses or they have a naturally mild reaction to the venom. Antibody molecules are produced as a result of the reaction of the animal’s immune systems to the foreign venom molecules. These are used to make life-saving antivenoms for humans. Molecular research aimed at making synthetic antivenoms is in progress.
Spider bites and venoms
- Those at greatest risk, as with any toxin, are the very young or elderly and those with pre-existing cardiovascular disease.
- Suspected funnel-web or mouse spider bites should always be treated as quickly as possible by applying a pressure bandage and immobilising the victim (do not cut the wound or apply a tight tourniquet).
- Bandaging is not necessary for Redback Spider bites. Applying pressure worsens the pain that often comes with Redback bites.
- The application of a cold pack may help if the bite is painful. For most spider bites, no other first aid is necessary.
- Always seek medical attention for any suspected funnel-web, mouse or Redback Spider bite and for any other bite if symptoms develop or persist.
- Catch the spider for positive identification if you can.
- Spider bites and venoms
- Spider bites and venoms
