A circuit between two brain regions appears to play a big role in binge drinking. New research with mice suggests manipulating the circuit could be a target for treatment.
The two brain areas—the extended amygdala and the ventral tegmental area—have been implicated in alcohol binge drinking in the past. However, this is the first time that the two areas have been identified as a functional circuit, connected by long projection neurons that produce a substance called corticotropin releasing factor, or CRF for short.
“The puzzle is starting to come together, and is telling us more than we ever knew about before,” says Todd Thiele of UNC-Chapel Hill, whose work appears in the journal Biological Psychiatry. “We now know that two brain regions that modulate stress and reward are part of a functional circuit that controls binge drinking and adds to the idea that manipulating the CRF system is an avenue for treating it.”
The extended amygdala has long been known to respond to psychological stress and anxiety. The ventral tegmental area responds to the rewarding properties of natural reinforcers, such as food, but also to drugs and alcohol.
Thiele and colleagues found that alcohol, a physiological stressor, activates the CRF neurons in the extended amygdala, which directly act on the ventral tegmental area. These observations in mice suggest that when someone drinks alcohol, CRF neurons become active in the extended amygdala and act on the ventral tegmental area to promote continued and excessive drinking, culminating in a binge.
Thiele says the findings could shed light on future pharmacological treatments to curb binge drinking and may help prevent the transition to alcohol dependence.
“It’s very important that we continue to try to identify alternative targets for treating alcohol use disorders,” Thiele says. “If you can stop somebody from binge drinking, you might prevent them from ultimately becoming alcoholics.
“We know that people who binge drink, especially in their teenage years, are much more likely to become alcoholic-dependent later in life.”
The National Institute on Alcohol Abuse and Alcoholism funded the study.
Source: UNC-Chapel Hill