Narrator:        This is Science Today. Sexual rejection is enough to make anyone feel like having a drink, including fruit flies. New research at the University of California, San Francisco shows that sex-deprived male fruit flies are more likely to drink alcohol to excess than those who've had sex. And it seems that a tiny molecule in the fly's brain, called neuropeptide F, is responsible for this behavior.

Heberlein:     We'd looked at the levels of neuropeptide F in flies that had either been rejected or mated and found that there was a very large difference in their expression.

Narrator:        Study leader Ulrike Heberlein says that the protein is very similar to a human molecule called neuropeptide Y that has been shown to play a role in excessive drinking and drug abuse.

Heberlein:     There are these connections out there and it would be extremely exciting to try to prove our hypothesis that neuropeptide Y is this crucial transducer between the experience and the drinking.

Narrator:        Such a discovery could one day lead to drug therapies for alcohol abuse. For Science Today, I'm Larissa Branin.