Cocaine change the way genes function in the brain
Prolonged exposure to cocaine can cause permanent changes in how genes are turned on and off in the brain, a finding that could develop more effective treatments for many types of addictions.
A mouse study conducted by the team of Ian Maze, of Mount Sinai School of Medicine in New York, found that chronic cocaine addiction prevented a specific enzyme to carry out its work of elimination of some genes in the brain’s pleasure circuits.
This effect was eager than rodents more drugs.
The research helps explain how cocaine use changes the brain, said Dr. Nora Volkow, director of the National Institute on Drug Abuse, part of the National Institutes of Health, which funded the study published in the journal Science.
“This discovery is enabling a new understanding of how the repeated use of drugs in the long term modifies the function of neurons,” Volkow said in a telephone interview.
For the study, the researchers administered to a group of young mice repeated doses of cocaine and other, repeated doses of saline and then single cocaine.
The authors found that one way that cocaine alters the brain’s reward circuitry is through repression 9A gene, which produces an enzyme that plays a key role in gene activation and deactivation.
Other studies have found that animals exposed to cocaine for a period of time are subject to drastic changes in how genes are turned on and off, and develop a strong preference for cocaine.
This work helps explain how this happens, Volkow said, and even lead to new ways of overcoming addiction.
In the study, Maze and his colleagues showed that these effects could be reversed by increasing the activity of the gene 9A.
“When that is done, completely reversed the effects of chronic use of cocaine,” he added.
Maze noted that this mechanism will not only reduce dependence on cocaine and could lead to a new area of research in addictions to other drugs, alcohol and even nicotine.
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