Researchers from the University of Toronto report the discovery of the biological basis that may illuminate the observed connection between pain and anxiety. The study focused on the connections between neurons in the anterior cingulate cortex (ACC) region of the brain. Pain can become chronic as neurons become more efficient at transmitting pain signals via repeated use, a process called “long term potentiation” or LTP. Previous work in animal models of chronic pain demonstrated that LTP occurs in the ACC, and that inhibiting LTP reduces chronic pain. However, how LTP in the ACC differs in chronic pain and anxiety was not known, nor why the 2 would interact to result in more pain in anxiety sufferers, and more anxiety in pain sufferers.
In the latest research, the team identified 2 different forms of LTP that can occur in the same cortical synapse. They were termed pre-LTP and post-LTP because they occur before and after the synapse, respectively. The discovery that pre-LTP is associated with anxiety and post-LTP is associated with pain explains why these conditions are linked, as both result in an increase in transmission of the glutamate signal between neurons in the ACC. The team also identified a molecule, called NB001, which can specifically block neuronal pre-LTP, and has powerful analgesic effects in animal models of chronic pain. Further investigation of the signaling pathways of pre- and post-LTP should reveal new drug targets for treating pain and anxiety.
Pain and anxiety are risk factors for postsurgical pain! Read a synopsis here.
Read an earlier news release about pain and anxiety, click here.
To read more about this news release, click here.