2,3,7,8-Tetrachlorodibenzo-p-dioxin enhances responsiveness to post-ingestive satiety signals.
The present study was designed to characterize the hypophagia that is a salient feature of the 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD)-induced wasting syndrome. When TCDD-treated Long-Evans (L-E; dose 50 micrograms/kg) and Han-Wistar (H-W; 3000 micrograms/kg) rats were offered a simultaneous choice of three diets differing in their macronutrient composition, no selective aversion was seen to any of the varieties, although total energy intake decreased drastically and especially so in L-E rats. Further studies in H-W rats showed that TCDD treatment leads to a permanent retardation of weight gain accompanied by a decreased intake of chow and of a 10% sucrose solution, and to a reduced or unchanged consumption of water. In contrast, there was a progressive increase in saccharin drinking (when offered as the only choice) in TCDD-dosed rats with time. TCDD-treated animals also tended to consume a greater proportion of their daily feed intake during the daytime. These results imply that TCDD induces aversion to eating energy-providing food, irrespective of its type, and that TCDD exerts this at least in part by sensitizing the rats to post-ingestive satiety factors.
Pohjanvirta
R
R
Department of Environmental Hygiene and Toxicology, National Public Health Institute, Kuopio, Finland.
Tuomisto
J
J
D000818:Animals; D001835:Body Weight / Q000187:drug effects; D002940:Circadian Rhythm; D004327:Drinking Behavior / Q000187:drug effects; D002149:Energy Intake; D004734:Energy Metabolism / Q000187:drug effects; D005247:Feeding Behavior / Q000187:drug effects*; D008297:Male; D000072317:Polychlorinated Dibenzodioxins / Q000494:pharmacology*; D051381:Rats; D012439:Saccharin; D012527:Satiation / Q000187:drug effects*
D000072317:Polychlorinated Dibenzodioxins; D012439:Saccharin