NPY-Y1 Receptors in Dorsal Periaqueductal Gray Mediate Food Consumption, Preference for Sucrose in Pre-Induced Rats, and Prevent Its Alcohol Intake

Periaqueductal gray (PAG) is a well-documented region on integrated defensive responses and anxiety-like behavior. Recently PAG was linked to drugs/alcohol consumption, mainly in the relapse state, and associated with anxiety. Interestingly, NPY is probably the major anxiolytic endogen neuropeptide, besides its well-recognized orexigenic action mediated mainly by NPY-Y 1 and NPY-Y 5 receptors respectively. Herein, we addressed the role of the NPY-Y 1 receptors in the dorsal (D)-PAG on anxiety-like behavior through defensive burying test, as well as the food, sucrose and alcohol consumption in water and food free access male Wistar rats. A twice repeated sucrose-fading paradigm since juvenile age as the alcohol intake initiation procedure was performed in other group of rats. Present results confirmed that intra D-PAG NPY produced anxiolytic-like behaviors. Additionally, injected NPY into D-PAG significantly increased both the food and sucrose intake and decreased the alcohol consumption in a free-choice sucrose and alcohol fluid access model. Moreover, intra D-PAG of a selective NPY-Y 1 receptor antagonist (BIBP3226) produced the opposite effects that those by NPY. Our results suggest that NPY-Y 1 in D-PAG may be a target for the anxiolytic, orexigenic and alcohol intake preventive actions of NPY.