A woman, who was not able to feel pain since birth, has felt it for the first time, thanks to that drug, the prescription of which is given for opioid overdoses. She enjoyed the experience of being burned with a laser. With this method, a painful condition like arthritis can also be treated.
There are only few people who are born without the capability of feeling pain. Often, these individuals are seen suffering from various injuries while young. Toddlers might suffer from tumbles, encounter with hot or sharp objects or suffer increased knocks, while babies chew their lips and toes, fingers etc. until they bleed.
The main cause of this disorder is a genetic mutation, owing to which the ion channels transporting sodium across the sensory nerves are reduced. In the absence of these channels also termed as Nav1.7 channels, pain cannot be communicated by nerve cells. Researchers starting making compounds through which Nav1.7 channels might be blocked thinking that the pain can be blocked even in people without this disorder.
John Wood, at University College London stated that it was a fantastic drug target. Pharma companies want to make several drugs. Even though few compounds succeeded, a total pain-loss that is seen in people lacking that channel naturally, wasn’t brought about. John Wood said:
“It looked like a fantastic drug target. Pharma companies went bananas and made lots of drugs.”
For finding out the reason, mice that were modified genetically for lacking Nav1.7 were studied by Wood as well as his colleagues. There is no feeling of pain in these animals and no reaction was shown when the tails were exposed to extreme cold temperatures or extreme hot temperatures.
A close analysis of the nerves of rodents showed that mice that lacked Nav1.7 saw a heavy increase in expression of genes that were responsible to the natural painkiller of the body, Opioid Peptides. The mice tend to make more of these peptides and this explains the reason as to why people who lack the channel don’t feel the pain too. If this was the case, the disorder may be reversed by a drug that leads to blockage of action of opioid peptides.
When nalaxone, a drug blocking opiod receptors as well as treating heroin and morphine overdoses was given to mice, the pain was felt again by the animals. The same effect was seen in people as well. When this drug was given to a 39 year old woman, who wasn’t capable of feeling the pain since birth, she felt pain for the first time. She stated that she enjoyed the experiment a lot and hopes that this drug can be used for treatment of any child having the same condition.
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