Abstract
Objective: Neuropeptide Y (NPY), given centrally augments food intake and the motivation to work for
palatable food. Here, the brain regions were identified through which NPY increases food intake and
motivation.
Methods: NPY was infused into three brain regions implicated in food intake and motivation: the lateral
hypothalamus (LH), nucleus accumbens shell (NAc), and ventral tegmental area (VTA). Motivation for
sucrose was assessed using a progressive-ratio schedule of reinforcement in which the effort to obtain
successive rewards increased incrementally. To disentangle the effects of NPY on motivation for palatable
food from food consumption, free-feeding experiments were performed in which animals had ad libitum
access to sucrose pellets.
Results: Infusion of NPY into either VTA or NAc increased the motivation to respond for sucrose,
whereas infusion of NPY in either NAc or LH increased sucrose consumption. In addition, the effect of
intra-VTA NPY on motivation for food was attenuated after pretreatment with the dopamine receptor
antagonist alpha-flupenthixol.
Conclusions: Specific limbic substrates through which NPY influences consumption of and motivation
for palatable food were identified by these data. The motivational effects of NPY are exerted through the
VTA, its consummatory effects through the LH, and the NAc is involved in both.
palatable food. Here, the brain regions were identified through which NPY increases food intake and
motivation.
Methods: NPY was infused into three brain regions implicated in food intake and motivation: the lateral
hypothalamus (LH), nucleus accumbens shell (NAc), and ventral tegmental area (VTA). Motivation for
sucrose was assessed using a progressive-ratio schedule of reinforcement in which the effort to obtain
successive rewards increased incrementally. To disentangle the effects of NPY on motivation for palatable
food from food consumption, free-feeding experiments were performed in which animals had ad libitum
access to sucrose pellets.
Results: Infusion of NPY into either VTA or NAc increased the motivation to respond for sucrose,
whereas infusion of NPY in either NAc or LH increased sucrose consumption. In addition, the effect of
intra-VTA NPY on motivation for food was attenuated after pretreatment with the dopamine receptor
antagonist alpha-flupenthixol.
Conclusions: Specific limbic substrates through which NPY influences consumption of and motivation
for palatable food were identified by these data. The motivational effects of NPY are exerted through the
VTA, its consummatory effects through the LH, and the NAc is involved in both.
| Original language | English |
|---|---|
| Pages (from-to) | 1216-1219 |
| Number of pages | 4 |
| Journal | Obesity (Silver Spring) |
| Volume | 22 |
| Issue number | 5 |
| DOIs | |
| Publication status | Published - 2014 |