Hormone linked to brain's food cravings

NEW HAVEN, Conn., Nov. 16 (UPI) -- U.S. medical scientists have found ghrelin, a hormone produced in the stomach, induces food intake and is linked to cravings for food.

Yale School of Medicine researchers say ghrelin was previously associated with growth hormone release, appetite, learning and memory but has now been linked with the reward circuitry of the brain that regulates food cravings.

According to lead author Professor Tamas Horvath, components of the reward circuitry of the ventral tegmental area, or VTA, may be responsible for overeating and addiction.

Horvath and colleagues found ghrelin could signal directly in the VTA region and activate dopamine neuronal activity, which controls reward-associated behavior to promote interest in food as a reward. As a default, ghrelin's action may also alter seeking of drugs and substances that work through the same pathways.

"We found that if we selectively block ghrelin in this part of the brain, we can suppress feeding or the need to seek out food and energy," said Horvath. "It also suggests that perhaps it could interfere with the need to seek out drugs as well."

The study appeared in the Oct. 19 online issue of The Journal of Clinical Investigation.