The finding by scientists at UCSF was published online Sunday (December 12) by Nature Neuroscience in advance of publication in the journal.
The UCSF researchers showed that when the normal function of insulin-like molecules in the brain of fruit flies is reduced, the intoxicating effect of alcohol increases. Earlier research has demonstrated that the flies and humans display many of the same vulnerabilities and behavioral responses to alcohol.
"This finding opens promising new avenues for the treatment of alcoholism," said Ulrike Heberlein, PhD, UCSF professor of anatomy and senior author on the paper. "Insulin is already known to act in the nervous system to regulate food intake, so it makes sense that it would influence the response to other substances the body senses as rewards, such as alcohol or drugs of abuse."
Insulin functions in the brains of animals from worms to mammals, and the pathway by which it influences behavior has been conserved throughout millions of years of evolution, Heberlein said, and research has recently revealed that insulin reduces the presence of the molecule that transports dopamine in the brain.
"In animals and humans, dopamine in the brain affects the response to both food and drugs. We are starting to see that in addition to its importance in sugar metabolism, insulin regulates release of neurotransmitters and may be crucial in determining the response to addictive drugs."
In her pioneering 10-year research effort to determine the genetic basis of alcohol-induced behavior, Heberlein has employed an apparatus she calls the inebriometer, in which normal flies and those with known mutatio
Contact: Wallace Ravven
University of California - San Francisco