The Link Between Stress and Depression

We've been talking about stress and depression and it got me thinking - what's the actual link between the two? Not theoretical, but the actual biological link? If the link was found then maybe there would be a way to be able to block it. So instead of administering antidepressant drugs like Prozac that increase serotonin levels in the brain, there would be a way to stop it in the first place. It turns out in September 2012 researchers at UWashington found the link: a peptide called CRF. CRP plays part in the area of the brain known for motivation, pleasure, and social behavior. When something happy happens, CRP binds to a receptor and increases the release of dopamine. The researchers experimented with mice and flushed their brains with CRP and saw what cage they preferred (in one cage they received CRP and the other they didn't). As expected, the mice preferred the cage where they received CRP. They then stressed out the mice and performed the same experiment, only this time the mice wanted to spend less time in the cage with CRP. This effect lasted for more than three months. These results make me wonder: if one occurance of severe stress can have an impact for more than three months, what happens if the stress is repeated every month or so? Would the person then permanently be in this state of depression? Hopefully some form of a blocking agent can be found.

Original article: http://articles.latimes.com/2012/sep/19/science/lat-sci-sn-stress-and-depression-linked-in-the-brain-20120919

Link to the study: http://www.nature.com/nature/journal/vaop/ncurrent/full/nature11436.html