Could drug addiction treatment of the future be as simple as an on/off switch in the brain? A study in rats has found that stimulating a key part of the brain reduces compulsive cocaine-seeking and suggests the possibility of changing addictive behavior generally . The study, published in the journal Nature, was conducted by scientists at the Intramural Research Program of the National Institute on Drug Abuse (NIDA), part of the National Institutes of Health, and the University of California, San Francisco.
In a recent paper in Nature Neuroscience, two researchers at the Scripps Research Institute in Florida report that obese rats with extended access to what they deemed “palatable food” — bacon, sausage, cheesecake, pound cake, frosting and chocolate — exhibited compulsive like eating behavior, much like rats with extended access to cocaine or heroin . This compulsive eating meant that they continued eating despite negative ramifications, in this case a flash of light signaling an oncoming electric shock administered to their foot. This lack of control over behavior with known negative consequences is a hallmark of both drug addiction and obesity. The investigators found that just like drug addicted rats, these obese rats had fewer striatal (a region of the forebrain) dopamine D2 receptors; this is responsible for the observed dampening of their neural reward responses to the food, which caused them to continue to eat, seeking that elusive high.
Researchers have identified a key epigenetic mechanism in the brain that helps explain cocaine’s addictiveness, according to research funded by the National Institute on Drug Abuse (NIDA), part of the National Institutes of Health.
The study, published in the January issue of the journal Science, shows how cocaine affects an epigenetic process (a process capable of influencing gene expression without changing a gene’s sequence) called histone methylation. These epigenetic changes in the brain’s pleasure circuits, which are also the first impacted by chronic cocaine exposure, likely contribute to an acquired preference for cocaine.