Rejected fruit flies use alcohol to cope
Fruit flies that haven't mated recently are more likely to ingest alcohol, according to a recent study.
Chronically sex-deprived fruit flies will take refuge in booze, while just-mated flies are more likely to take a pass on the alcohol, new research suggests.Skip to next paragraph
Subscribe Today to the Monitor
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. But NPF also can be turned up by outside factors, including alcohol. (Flies have no trouble finding alcohol, which is created by their favorite 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. She did the research as a part of the Ulrike Heberlein's lab there.
"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 behaviors that will return the levels back to normal," Shohat-Ophir told LiveScience.
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 behaviors 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.
Fly dates and drinking
To see how sex impacts fly drinking, the researchers placed virgin male flies in a dish with either virgin females or with already-mated females, which unlike the virgins will reject the males.