title: Effect of dopamine D1 and D2 receptor antagonism in the lateral hypothalamus on the expression and acquisition of fructose-conditioned flavor preference in rats.
abstract: The attraction to sugar-rich foods is influenced by conditioned flavor preferences (CFP) produced by the sweet taste of sugar (flavor-flavor learning) and the sugar's post-oral actions (flavor-nutrient) learning. Brain dopamine (DA) circuits are involved in both types of flavor learning, but to different degrees. This study investigated the role of DA receptors in the lateral hypothalamus (LH) on the flavor-flavor learning produced the sweet taste of fructose. In an acquisition study, food-restricted rats received bilateral LH injections of a DA D1 receptor antagonist (SCH23390), a D2 antagonist (RAC, raclopride) or vehicle prior to 1-bottle training sessions with a flavored 8% fructose+0.2% saccharin solution (CS+/F) and a less-preferred flavored 0.2% saccharin solution (CS-). Drug-free 2-bottle tests were then conducted with the CS+ and CS- flavors presented in saccharin. The fructose-CFP did not differ among groups given vehicle (76%), 12 nmol SCH (78%), 24 nmol (82%) or 24 nmol RAC (90%) during training. In an expression study with rats trained drug-free, LH injections of 12 or 24 nmol SCH or 12-48 nmol RAC prior to 2-bottle tests did not alter CS+ preferences (77-90%) relative to vehicle injection (86%). Only a 48 nmol SCH dose suppressed the CS+ preference (61%). The minimal effect of LH DA receptor antagonism upon fructose flavor-flavor conditioning differs with the ability of LH SCH injections to block the acquisition of glucose flavor-nutrient learning.
authors.affiliation: Department of Psychology, Queens College, City University of New York, NY, NY, United States.
authors.forename: Nicole J
authors.initials: NJ
authors.lastname: Amador
authors.affiliation: Neuropsychology Doctoral Subprogram, Graduate Center, City University of New York, NY, NY, United States.
authors.forename: Francis M
authors.initials: FM
authors.lastname: Rotella
authors.affiliation: Neuropsychology Doctoral Subprogram, Graduate Center, City University of New York, NY, NY, United States.
authors.forename: Sonia Y
authors.initials: SY
authors.lastname: Bernal
authors.affiliation: Neuropsychology Doctoral Subprogram, Graduate Center, City University of New York, NY, NY, United States.
authors.forename: Danielle
authors.initials: D
authors.lastname: Malkusz
authors.affiliation: Neuropsychology Doctoral Subprogram, Graduate Center, City University of New York, NY, NY, United States.
authors.forename: Julie A Dela
authors.initials: JA
authors.lastname: Cruz
authors.affiliation: Department of Psychology, Queens College, City University of New York, NY, NY, United States.
authors.forename: Arzman
authors.initials: A
authors.lastname: Badalia
authors.affiliation: Department of Psychology, Queens College, City University of New York, NY, NY, United States.
authors.forename: Sean M
authors.initials: SM
authors.lastname: Duenas
authors.affiliation: Department of Psychology, Queens College, City University of New York, NY, NY, United States.
authors.forename: Maruf
authors.initials: M
authors.lastname: Hossain
authors.affiliation: Department of Psychology, Queens College, City University of New York, NY, NY, United States.
authors.forename: Meri
authors.initials: M
authors.lastname: Gerges
authors.affiliation: Department of Psychology, Queens College, City University of New York, NY, NY, United States.
authors.forename: Salomon
authors.initials: S
authors.lastname: Kandov
authors.affiliation: Department of Psychology, Brooklyn College, City University of New York, NY, NY, United States.
authors.forename: Khalid
authors.initials: K
authors.lastname: Touzani
authors.affiliation: Neuropsychology Doctoral Subprogram, Graduate Center, City University of New York, NY, NY, United States; Cognition, Brain and Behavior Doctoral Subprogram, Graduate Center, City University of New York, NY, NY, United States; Department of Psychology, Brooklyn College, City University of New York, NY, NY, United States.
authors.forename: Anthony
authors.initials: A
authors.lastname: Sclafani
authors.affiliation: Neuropsychology Doctoral Subprogram, Graduate Center, City University of New York, NY, NY, United States; Department of Psychology, Queens College, City University of New York, NY, NY, United States. Electronic address: richard.bodnar@qc.cuny.edu.
authors.forename: Richard J
authors.initials: RJ
authors.lastname: Bodnar
mesh_terms: D000704:Analysis of Variance; D000818:Animals; D003213:Conditioning, Psychological / Q000187:drug effects*; D018492:Dopamine Antagonists / Q000494:pharmacology*; D065127:Dopamine D2 Receptor Antagonists; D004305:Dose-Response Relationship, Drug; D005518:Food Preferences / Q000502:physiology*; D007026:Hypothalamic Area, Lateral / Q000187:drug effects*; D008297:Male; D051381:Rats; D017207:Rats, Sprague-Dawley; D017447:Receptors, Dopamine D1 / Q000037:antagonists & inhibitors; D012439:Saccharin / Q000008:administration & dosage; D013549:Sweetening Agents / Q000008:administration & dosage; D013649:Taste / Q000187:drug effects*
chemical_list: D018492:Dopamine Antagonists; D065127:Dopamine D2 Receptor Antagonists; D017447:Receptors, Dopamine D1; D013549:Sweetening Agents; D012439:Saccharin
keywords: Flavor–flavor learning; Raclopride; SCH23390; Saccharin; Sweet taste