Obesity may make ignoring ‘food cues’ even harder

"When obesity-prone rats learned to recognize a certain sound as the cue for food availability, a key receptor appeared more frequently on the surface of certain cells in the reward center. But similar changes in this receptor were not seen in obesity-resistant rats.

What’s more, when researchers used a drug to block the receptors, called CP-AMPA receptors or CP-AMPARs, the food cue no longer triggered the obesity-prone rats to seek out food—even though they still showed signs that they recognized the cue.

It was as if they had switched from eagerly trying to trace the smell of pizza and go find its source to smelling it and not even getting up to find it.

Although a drug that could do the same for humans isn’t yet available, the researchers hope their work will help form the basis for new understanding of human obesity’s roots in our genes, learned behaviors and the brain."