title: Effect of chronic intake of sweet substance on nociceptive thresholds and feeding behavior of Rattus norvegicus (Rodentia, Muridae).
abstract: The investigation of the influence of sweetened food on feeding behavior targeted to non-sucrose nutrients as well as the sensitivity to painful stimuli in isolated and grouped animals is the aim of the present work. The tail withdrawal latencies in the tail-flick test (a spinal reflex) were measured before and immediately after the treatment with tap water or sucrose (62, 125 or 250 g/l). Our findings suggest that: (a) The analgesic effect of sucrose intake depends on the concentration of sucrose solution and on the time during which the solution is consumed; (b) the most effective concentration of sucrose followed by antinociceptive effect was the one of 250 g/l in both isolated and grouped animals; (c) considering the individually caged rats, the intake of sucrose in the highest concentration (250 g/l) was the smallest as compared with the consumption of sucrose in more diluted solutions (62.5 and 125 g/l), but this higher sweetened solution was followed by antinociception; (d) animals treated with concentrated sucrose solution ate smaller quantities of pellets than animals treated with tap water; (e) tonic intake of highly concentrated sweet substance seems to be crucial for the increase of the nociceptive threshold in our model of sweet substance-induced antinociception.
authors.affiliation: Laboratory of Neuroanatomy and Neuropsychobiology, Department of Pharmacology, School of Medicine of Ribeirão Preto of the University of São Paulo (FMRP-USP), Avenue of Bandeirantes, 3900, Ribeirão Preto (SP) 14049-900, Brazil.
authors.forename: E N
authors.initials: EN
authors.lastname: Segato
authors.forename: E C C
authors.initials: EC
authors.lastname: Rebouças
authors.forename: R L
authors.initials: RL
authors.lastname: Freitas
authors.forename: M P T
authors.initials: MP
authors.lastname: Caires
authors.forename: A V
authors.initials: AV
authors.lastname: Cardoso
authors.forename: G C C
authors.initials: GC
authors.lastname: Resende
authors.forename: G
authors.initials: G
authors.lastname: Shimizu-Bassi
authors.forename: D H
authors.initials: DH
authors.lastname: Elias-Filho
authors.forename: N C
authors.initials: NC
authors.lastname: Coimbra
mesh_terms: D000698:Analgesia; D000818:Animals; D019422:Dietary Sucrose / Q000008:administration & dosage*; D004326:Drinking; D004435:Eating / Q000187:drug effects*; D008297:Male; D009619:Nociceptors / Q000502:physiology; D010147:Pain Measurement; D051381:Rats; D017208:Rats, Wistar; D012996:Solutions; D013623:Tail; D013997:Time Factors
chemical_list: D019422:Dietary Sucrose; D012996:Solutions