Researchers at the University of North Carolina in Chapel Hill have succeeded in mapping the way an opioid receptor in the brain binds to a molecule similar to morphine. The receptor protein, known as the kappa opioid receptor, is one of four proteins in the brain that bind to opioids, but unlike the other three, it does not seem to trigger many of the unwanted side effects associated with opioid use. These include constipation, severe addiction, and the risk of overdose which can lead to death.
This recent discovery is built on the fact that the structure of the kappa opioid receptor had already been revealed. However, it’s mode of interaction with opioid molecules was not mapped out until now. The discovery could lead to alternative painkillers which would circumvent the well known issues morphine and stronger opioids come with.
Still, the kappa opioid receptor can also trigger a number of undesirable reactions. Hallucinations, dysphoria, anxiety, all of these have been suggested as possible side effects of drugs binding exclusively with this receptor. But the detailed mapping of its interaction with molecules could allow scientists to concoct drugs that would only trigger the effect related to paint relief.
The race to come up with alternatives to opioid pain killers is desperate, as over 60,000 people have overdosed on such medication in 2016 alone. The death count among US patients is as high as that of the Vietnam War, and the opioid crisis has recently been deemed a national health emergency by President Donald Trump. This new discovery is an encouraging step towards shifting patients and addicts away from this extremely dangerous class of chemicals. However, the authors of the research made it very clear that it will most likely take a few years before new medication is developed based on these findings.