Medial habenula is a mysterious little-studied region in the centre of the human brain. Its function is not fully understood and scientists are still trying to work out why do we have it at all. But now an international team of researchers, including scientists from the University of Sydney and Kolling Institute discovered a receptor believed to be linked to negative moods in there.
This work was not an easy one. Scientists have been working on this brain region for eight years. Part of the reason why it took so long is that the medial habenula is poorly understood. This new receptor, marked as glycine gated [N-methyl-D-aspartate receptor] NMDA receptor, could eventually become a drug target for various therapies, treating a number of conditions that negative mood is a symptom of.
This newly discovered glycine gated NMDA receptor is quite an interesting one. While usually other NMDA receptors require two different neurotransmitter molecules for its activation, this one only needs one. This makes this receptor quite unique from the other ones and it is a good thing. This means that scientists can design medicine that affect it exclusively without touching other receptors.
It is a huge problem with psychiatric drugs – they othen affect the entire brain, which causes a multitude of side effects. This glycine gated NMDA receptor is different from other ones because it only needs one neurotransmitter – glycine – to activate it. This allows creating much more targeted medicine, which would produce fewer negative side effects. Dr Yo Otsu, one of the authors of the study, explained: “Receptors direct brain function and are the target of approximately 40 % of all current medicines. Therefore, the discovery of this rare type of receptor and its role in modulating anxiety and the effects of negative experiences means it has the potential to be a highly specific target for mood regulating drugs”.
Depression, anxiety disorder and many other conditions have a symptom of negative moods. This is not just a simple matter of not feeling well. Negative moods can be debilitating, destroying motivation and leaving people unable to get out of bed. Good drugs that would target this glycine gated NMDA receptor very precisely and would not cause severe side effects would be a great medical advancement for thousands of people. But before that is possible, more research needs to be done.
Scientists will not try to figure out what is the role of the glycine gated NMDA receptor in medial habenula. At the same time, hopefully, we will find out more information about that brain region. This research is likely to take several years more, but at the end we should have a better understanding about our brain and more effective medicine for some mental issues.
Source: University of Sydney