Hunger enhances food odor attraction in mice
Oral presentation
Hunger is a powerful motivational state that intensely drives behaviors predictive of food consumption. However, mechanisms by which internal state shapes olfactory circuits remain poorly understood.
Here, by using a simple and robust two-choice assay to investigate hunger dependent odor responses and optogenetic methods, we identified a neuronal mechanism by which hunger enhances attraction to food odors over other olfactory cues. By activating each axon of agouti-related peptide (AGRP) neurons, we found that AGRP neurons promote food odor attraction through projections to the paraventricular thalamus. Studies with KO mice and agonist/antagonist injections showed that food odor attraction by AGRP neurons act through Neuropeptide Y and its receptor NPY5R.
We uncovered molecular features that are essential for one such neuromodulatory pathway, as NPY from AGRP neurons opens a thalamic hunger gate for specific olfactory inputs that carry an NPY5R encryption. More generally, these studies provide insight into how internal state guides olfactory behavior.
All animal procedures followed the ethical guidelines outlined in the National Institutes of Health Guide for the Care and Use of Laboratory Animals, and all protocols were approved by the Institutional Animal Care and Use Committee (IACUC) at Harvard Medical School.
Here, by using a simple and robust two-choice assay to investigate hunger dependent odor responses and optogenetic methods, we identified a neuronal mechanism by which hunger enhances attraction to food odors over other olfactory cues. By activating each axon of agouti-related peptide (AGRP) neurons, we found that AGRP neurons promote food odor attraction through projections to the paraventricular thalamus. Studies with KO mice and agonist/antagonist injections showed that food odor attraction by AGRP neurons act through Neuropeptide Y and its receptor NPY5R.
We uncovered molecular features that are essential for one such neuromodulatory pathway, as NPY from AGRP neurons opens a thalamic hunger gate for specific olfactory inputs that carry an NPY5R encryption. More generally, these studies provide insight into how internal state guides olfactory behavior.
All animal procedures followed the ethical guidelines outlined in the National Institutes of Health Guide for the Care and Use of Laboratory Animals, and all protocols were approved by the Institutional Animal Care and Use Committee (IACUC) at Harvard Medical School.