Thaindian News

Washington, March 22 (IANS) Sex-deprived fruit flies are more likely to ingest alcohol, while just-mated ones are more likely to take a pass on the booze, a new study suggests.

The alcoholic tendencies of the chronically rejected flies seem to be a result of decreased levels of a brain chemical called neuropeptide F (NPF), which researchers think plays a role in the fly’s reward system.

When the fly does something that would be good for it evolutionarily, such as mating or eating food, an internal mechanism increases NPF levels, the Christian Science Monitor reports.

But NPF also can be turned up by outside factors, including alcohol. (Flies have no trouble finding alcohol, which is created by their favourite food: yeast on rotting fruit.)

“What we discovered was an interplay between internal rewards and external rewards,” said study researcher Galit Shohat-Ophir of the Howard Hughes Medical Institute’s Janelia Farm Research Campus, in Virginia.

“There’s some kind of system in the brain, which we think NPF is regulating, that represents the level of internal reward.

“If there is perturbation in the level of NPF in the brain, there are behaviours that will return the levels back to normal,” the Monitor quoted Shohat-Ophir as saying.

Humans have a similar neuropeptide, called neuropeptide Y, in their brains. Researchers studying humans and other mammals have found a link between NPY and reward-related behaviours such as eating (and overeating).

NPY is known to inhibit alcohol consumption, and mutations in NPY have been seen in groups of alcoholics in correlational studies.

Researchers have been working with NPY in mammals and NPF in flies to get a better understanding of alcoholism and to possibly design treatments for it.

“From the experiments we’ve done, our hypothesis is that it (alcohol) affects the fly’s brain in a way similar to how it affects ours,” Shohat-Ophir said. “The alcohol increases their NPF levels.”

The study was published in the journal Science March 15.