Neurotensin: effects of hypothalamic and intravenous injections on eating and drinking in rats.
To investigate a role for the brain-gut peptide neurotensin (NT) in ingestive behavior, changes in food and water intake of food-deprived rats were examined following injection of NT into the paraventricular hypothalamic nucleus (PVN) or the mesenteric vein. Unilateral PVN NT (2.5, 5.0, 10.0 micrograms/0.3 microliter) produced substantial dose-dependent reductions in total food intake 0.5, 1, and 4 hr postinjection. In contrast, PVN NT had no effect on water intake and produced no change in grooming, rearing, sleeping, resting or locomotor activity. Bilateral PVN NT at a high dose (10.0 micrograms/side) suppressed consumption of solid or liquid diet in food-deprived rats, but did not affect water intake in water-deprived rats. This specificity is consistent with a role for CNS NT in feeding behavior. Intravenous NT (1-1000 pmole/kg/min for 30 min) did not specifically suppress food intake; however, low doses did increase water intake in food-deprived rats. These findings do not support a role for plasma NT in feeding, but do suggest that it may play a role in drinking behavior.
D000818:Animals; D004305:Dose-Response Relationship, Drug; D004327:Drinking Behavior / Q000187:drug effects*; D005247:Feeding Behavior / Q000187:drug effects*; D005508:Food Deprivation; D006801:Humans; D007275:Injections, Intravenous; D007276:Injections, Intraventricular; D008297:Male; D009043:Motor Activity / Q000187:drug effects; D009496:Neurotensin / Q000008:administration & dosage / Q000494:pharmacology*; D010286:Paraventricular Hypothalamic Nucleus / Q000187:drug effects / Q000502:physiology*; D051381:Rats; D011919:Rats, Inbred Strains; D012890:Sleep / Q000187:drug effects; D013239:Stereotyped Behavior / Q000187:drug effects
D009496:Neurotensin