Neuron 65, 682–694 (2010)

Rats that regularly consume alcohol and are then denied it show increased activity in a specific brain region.

F. Woodward Hopf, at the University of California, San Francisco, and his colleagues gave rats access to either a 10% alcohol solution or sucrose for several weeks and then cut them off. After a few weeks of abstinence, the alcohol-exposed rats had increased neuronal firing in the core of the nucleus accumbens — a brain structure associated with motivation and addiction — but those that had consumed sucrose did not.

This elevated activity is linked to reduced numbers of a certain type of potassium channel that normally depresses neuronal firing. Alcohol-drinking rats that were given a drug to activate these channels — thus dampening firing in this brain region — were less likely to seek alcohol. Drugs that activate the channels in humans might prevent relapse to alcoholism, the authors say.