Study Shows Gene Changes in Brain Caused by Cocaine

Long-term cocaine use can alter the function of genes in the brain, leaving “pleasure circuits” stuck in the open position and increasing craving for the drug, according to a new animal study conducted by researchers at the Mount Sinai School of Medicine.

Reuters reported Jan. 9 that researcher Ian Maze and colleagues found that the gene 9A — which produces an enzyme responsible for switching other genes on and off — was repressed in the brains of mice given repeated doses of cocaine. Researchers also found that restoring the activity of gene 9A reversed cocaine preference and craving in lab mice.

“This finding is opening up our understanding about how repeated drug use modifies in long-lasting ways the function of neurons,” said Nora Volkow, director of the National Institute on Drug Abuse.

The research was published in the Jan. 8, 2010 issue of the journal Science.