Researchers uncover step in brain events leading up to addiction

Aug 15, 2010

A regulatory protein best known for its role in a rare genetic brain disorder also may play a critical role in cocaine addiction, according to a recent study in rats, funded by the National Institute on Drug Abuse (NIDA), a component of the National Institutes of Health. The study was published today in the journal Nature Neuroscience.

Researchers at the Scripps Research Institute in Jupiter, Fla. found that cocaine consumption increased levels of a regulatory protein called MeCP2 that shuttles back to the nucleus to influence in the brains of rats. As levels of MeCP2 increased in the brain, so did the animals' motivation to self-administer cocaine. This suggests that MeCP2 plays a crucial role in regulating cocaine intake in rats and perhaps in determining vulnerability to addiction.

"This discovery, using an animal model of addiction, has exposed an important effect of cocaine at the molecular level that could prove key to understanding compulsive drug taking," said Dr. Nora D. Volkow, director of NIDA. "It should open up new avenues of research on the causes and ways to counter the behavioral changes linked to addiction in humans."

This is the second time this year that a critical factor related to cocaine self-administration in rodents has been identified. In a study published in July in the journal Nature, Scripps researchers identified regulatory molecule miRNA-212 as playing a key role in cocaine intake. However, MeCP2 increased motivation for cocaine, whereas miRNA-212 had the opposite effect, suggesting that the latter plays a protective role against drug seeking.

In the current study, researchers discovered that the brain's balance between MeCP2 and miRNA-212 ultimately regulates cocaine intake. When the balance shifts toward MeCP2, cocaine intake increases. When the balance shifts toward miRNA-212, cocaine intake decreases. What determines the balance is not yet understood, however, and will be the focus of future research.

"This study represents another piece in the puzzle of determining vulnerability to cocaine addiction," said Paul J. Kenny, senior author on the study and an associate professor at Scripps. "If we can continue putting the pieces together, we may be able to determine whether there are viable treatments for this condition."

Explore further: Know the brain, and its axons, by the clothes they wear

Provided by NIH/National Institute on Drug Abuse

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getgoa
1 / 5 (2) Aug 15, 2010
we have known now that the mind can be taught to overcome addiction(http://www.scienc...1317.htm

I don't understand the causeway they are claiming to be significant. The drug is illegal-- no use in beating a dead horse.

If America would not have done research and establish such a medical significance then this phrase would be true:

But if there be any trees that are not fruitful, but wild, and fit for other uses, cut them down, and make engines, until thou take the city, which fighteth against thee.
Pramodkaimal
not rated yet Aug 16, 2010
what about other addictions especially to Cigarette.. do keep me posted on any information on this addictive nature. and how to Help ONE get over Cigarette smoking addiction (to help my friends out of this habbit)
moj85
not rated yet Aug 16, 2010
Correlation does not imply causation. Legitimate work in this field needs to look at what happens when you knock-down these genes/proteins and see behavioral cues, but this is difficult since MeCP2 is required for normal neuron function.

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