Anxiety disorders are the most common class of mental disorder in the United States, affecting nearly 40 million people aged 18 and older and costing our economy around $47 billion a year.
While many anxiety disorders are treatable, almost a third of people who suffer from them do not seek help in the form of medication or therapy.
A recent study points to a novel treatment for anxiety disorders that involves changing the acidity of an area of the brain considered central to the disorders: the amygdala.
The amygdala is the site of the brain’s fear response. It plays a central role in emotional behavior and is activated during periods of intense stress.
The brain chemistry of people with anxiety may make it more difficult for them to turn off activity in the amygdala.
Neuroscientists from the Uniformed Services University of the Health Sciences in Washington D.C. discovered that the brain chemistry of people with anxiety may make it more difficult for them to turn off activity in the amygdala. But by increasing the acid concentration in and around the amygdala, the scientists were able to reduce anxiety behavior, a finding that could potentially be used to help people cope with feelings of stress.
Using animal models, the researchers discovered that the increased acidity in the amygdala activated a protein channel on the surface of certain neurons. Once activated, this channel calms down these brain cells by reducing their firing patterns and limiting their overall activity.
If you remember high school chemistry, more acid equals a lower pH. The protein channel in the amygdala’s neurons appears to be highly sensitive to pH. It responds to a lowering of pH by working to shut down the brain cells and curb the anxiety response.
If you completely block this protein channel so it can't shut down the brain cells, the lab animals became more anxious. Similarly, when the animals were given a drug that increased the activity of the channel, the anxiety stopped.
The protein channel, currently known to neuroscientists by the abbreviation ASIC1α, may be a new therapeutic target to treat anxiety disorders. Since people who suffer from anxiety disorders often have other psychiatric illnesses such as clinical depression, it is possible that this channel may hold the key for a variety of mental health problems.
“Developing specific drugs that can stimulate these channels could provide a new way to treat anxiety and fear disorders such as post-traumatic stress and panic disorders,” said Maria Braga, one of the authors of the study.
The researchers caution that much more research is needed about the basic role of ASIC1α in other regions of the brain before scientists can develop such targeted treatments.
The study was published in the Journal of Neuroscience.