title: Endogenous opioids encode relative taste preference.
abstract: Endogenous opioid signaling contributes to the neural control of food intake. Opioid signaling is thought to regulate palatability, the reward value of a food item as determined by orosensory cues such as taste and texture. The reward value of a food reflects not only these sensory properties but also the relative value of competing food choices. In the present experiment, we used a consummatory contrast paradigm to manipulate the relative value of a sucrose solution for two groups of rats. Systemic injection of the nonspecific opioid antagonist naltrexone suppressed sucrose intake; for both groups, however, this suppression was selective, occurring only for the relatively more valuable sucrose solution. Our results indicate that endogenous opioid signaling contributes to the encoding of relative reward value.
authors.affiliation: Ernest Gallo Clinic and Research Center, University of California, San Francisco, Emeryville, CA 94608, USA. staha@phy.ucsf.edu
authors.forename: Sharif A
authors.initials: SA
authors.lastname: Taha
authors.forename: Ebba
authors.initials: E
authors.lastname: Norsted
authors.forename: Lillian S
authors.initials: LS
authors.lastname: Lee
authors.forename: Penelope D
authors.initials: PD
authors.lastname: Lang
authors.forename: Brian S
authors.initials: BS
authors.lastname: Lee
authors.forename: Joshua D
authors.initials: JD
authors.lastname: Woolley
authors.forename: Howard L
authors.initials: HL
authors.lastname: Fields
mesh_terms: D000818:Animals; D002755:Choice Behavior / Q000502:physiology*; D003259:Consummatory Behavior / Q000502:physiology; D004327:Drinking Behavior / Q000502:physiology; D005518:Food Preferences; D008297:Male; D009271:Naltrexone / Q000008:administration & dosage / Q000378:metabolism; D009292:Narcotic Antagonists / Q000008:administration & dosage / Q000378:metabolism; D009714:Nucleus Accumbens / Q000166:cytology / Q000378:metabolism; D018847:Opioid Peptides / Q000378:metabolism*; D011897:Random Allocation; D051381:Rats; D020318:Rats, Long-Evans; D015398:Signal Transduction / Q000502:physiology*; D013395:Sucrose / Q000008:administration & dosage; D013649:Taste
chemical_list: D009292:Narcotic Antagonists; D018847:Opioid Peptides; D013395:Sucrose; D009271:Naltrexone