The scientists at the Department of Energy's Brookhaven National Laboratory in Upton, N.Y., discovered increasing the brain level of receptors for dopamine, a pleasure-related chemical, can reduce use of cocaine by 75 percent in rats trained to self-administer it.

Earlier research produced similar findings for alcohol intake.

"By increasing dopamine D2 receptor levels, we saw a dramatic drop in these rats' interest in cocaine," said study lead author Panayotis Thanos. "This provides new evidence that low levels of dopamine D2 receptors may play an important role in not just alcoholism, but in cocaine abuse as well. It also shows a potential direction for addiction therapies."

The research is available online and is to appear in the July issue of the journal Synapse.