Naloxone administration following operant training of sucrose/water discrimination in the rat. Psychopharmacology (Berl) 1997 Feb;129(3):289-94
Date
02/01/1997Pubmed ID
9084069DOI
10.1007/s002130050193Scopus ID
2-s2.0-0031045275 (requires institutional sign-in at Scopus site) 35 CitationsAbstract
The suppression of food intake observed following naloxone administration has often been ascribed to palatability or taste. Unfortunately, many confounds become apparent when attempts are made to isolate such factors in the investigation of ingestive behaviors. In the present study, rats (two groups) were trained to discriminate either a 10% or 5% sucrose solution from water (0.1 ml). These mildly food deprived subjects (95% of free-feeding weight) were trained to press the appropriate lever in a two-lever operant chamber following sampling of sucrose or water; successful responding was reinforced by delivery of a 45 mg grain food pellet. Following random exposure to reduced sucrose concentrations tested under extinction, a sucrose concentration gradient (1.0, 0.5, 0.1, 0.05, 0.01 and 0.005% sucrose solution) was established for both training groups under i.p. saline administration. Data collected under i.p. saline were then compared to those collected following random i.pf1p4loxone administration (3.0, 1.0, 0.3 and 0.1 mg/kg). No significant differences were observed between the sucrose concentration gradients obtained under saline and those obtained under naloxone, suggesting that the anorectic effect of naloxone is not primarily determined by discrimination of sweet taste.
Author List
O'Hare EO, Cleary J, Bartz PJ, Weldon DT, Billington CJ, Levine ASAuthor
Peter J. Bartz MD Chief, Professor in the Pediatrics department at Medical College of WisconsinMESH terms used to index this publication - Major topics in bold
AnimalsConditioning, Operant
Discrimination Learning
Dose-Response Relationship, Drug
Food Preferences
Male
Naloxone
Narcotic Antagonists
Rats
Rats, Sprague-Dawley
Sucrose
Taste
Water
