Researchers from Wakayama Medical University, Hokkaido University, and Hyogo Medical University have clarified for the first time in the world Tmem45b, a substance that produces persistent, strong pain with a slight stimulus.
In nociceptive pain such as rheumatoid arthritis, surgery, trauma, and cancer, strong pain that persists with a slight stimulus, such as pain caused by movement or touch, appears.The cause of this pain is unknown, and it is said that it is difficult to suppress it with general medicine such as antipyretic analgesics.For this reason, people currently have no choice but to resort to medical narcotics such as morphine, but even then, it is considered an intractable pain that may not provide sufficient analgesia.
To identify the causative agent of persistent intense pain, the researchers first used mice to identify nerve fibers that transmit persistent intense pain.Next, they discovered a protein called Tmem45b by comparing substances expressed in nerve fibers that transmit persistent intense pain and those that do not.
Mice with Tmem45b developed persistent pain due to inflammation and wounding, whereas Tmem45b-deficient mice that the researchers generated did not develop persistent pain due to inflammation or wounding.In other words, Tmem45b is considered to be a substance that is activated in association with inflammation and wounds and produces persistent intense pain.
More interestingly, we found that Tmem45b is almost absent in the brain and is specifically expressed in some peripheral nerves.In other words, pain treatments targeting Tmem45b are expected to relieve pain without affecting the brain.Current medical narcotics act on areas of the brain that are not related to pain transmission, causing side effects such as respiratory depression, drowsiness, nausea, and dependence, which is a major problem. Pain relief has the potential to be a whole new Game Changer that solves these problems.
