Susceptibility to alcohol

In animals and humans, dopamine in brain affects the response to both food and alcohols.

A research carried out on fruit flies by scientists at the University of California, San Francisco has led to the speculation that insulin may determine susceptibility to alcohol.

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. 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," said Ulrike Heberlein, lead author of the study and professor of anatomy at UCSF.

"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," he added.

The scientists now want to study whether insulin acts in the brains of mice to affect the rewarding properties of abused drugs. If this turns out to be the case, it would make a compelling case for studying the potential connection between brain insulin and drug addiction in humans, concluded Heberlein.