Increased food intake by neuropeptide Y is due to an increased motivation to eat.
Neuropeptide Y (NPY), administered intracerebroventricularly, is a potent orexigenic agent. To determine if NPY-induced eating represented an increase in motivation to eat (e.g., hunger) rather than pathological or stimulus-bound eating, we determined its effect on eating in three paradigms, including lever press, appetitive passive avoidance and quinine-adulterated milk. NPY-injected mice consumed more milk when required to work for it in a lever press apparatus and tolerated shock to the tongue for drinking milk. Increasing the dose of NPY also allowed mice to overcome a taste aversion for quinine-adulterated milk. Overall, these studies support the hypothesis that NPY causes a specific increase in the motivation to eat, rather than nonspecific or stimulus-bound behavior.
Flood
J F
JF
VA Medical Center, Geriatric Research Educational and Clinical Center, St. Louis, MO 63109.
Morley
J E
JE
D000818:Animals; D001070:Appetitive Behavior / Q000187:drug effects; D004305:Dose-Response Relationship, Drug; D004435:Eating / Q000187:drug effects*; D004597:Electroshock; D005247:Feeding Behavior / Q000187:drug effects*; D007276:Injections, Intraventricular; D008297:Male; D051379:Mice; D009042:Motivation; D009478:Neuropeptide Y / Q000008:administration & dosage / Q000494:pharmacology*; D013649:Taste
D009478:Neuropeptide Y