New Study could Provide Treatment Option for Cocaine Addiction

Researchers from Michigan State University have found a target in the brain that can be used to reverse the addiction of cocaine.

A.J. Robison, a neuroscientist from the university said that cocaine increases feelings of pleasure because it acts on nucleus accumbens - the pleasure center of the brain.

According to National Institute of Drug Abuse (NIDA), cocaine is a powerfully addictive central nervous system stimulant that is snorted, injected, or smoked. Crack is cocaine hydrochloride powder that has been processed to form a rock crystal that is then usually smoked. Users risk heart attacks, respiratory failure, strokes, seizures, abdominal pain, and nausea. In rare cases, sudden death can occur on the first use of cocaine or unexpectedly afterward.

"Understanding what happens molecularly to this brain region during long-term exposure to drugs might give us insight into how addiction occurs," said Robison, assistant professor in the Department of Physiology and the Neuroscience Program.

Cocaine activates production of two proteins in the nucleus accumbens - one related to addiction and the other to learning. The proteins tend to increase each other's levels in the cell. Robison describes the process as a "feed-forward loop".

"At every level that we study, interrupting this loop disrupts the process that seems to occur with long-term exposure to drugs," said Robison. He had conducted the study while he was at Mount Sinai School of Medicine in New York City.

The study team assessed the role of these two proteins in mouse models. They found that increasing the protein linked to addiction made the mice behave like they were on cocaine (even when the drug wasn't given). And, lowering the activity of protein associated with learning lead to the mice getting over their addiction of the drug.

"The increased production of these proteins that we found in the animals exposed to drugs was exactly paralleled in a population of human cocaine addicts. That makes us believe that the further experiments and manipulations we did in the animals are directly relevant to humans," he said.

Robison added that studying the effects of cocaine on molecules in the brain can help researchers design treatments against the addiction.

The study is published in the Journal of Neuroscience.

Centers for Disease Control and Prevention says that over 400,000 emergency room visits each year are cocaine-related in the United States, while over 5,000 people die from overdose.