Are delta-opioid receptors involved in the regulation of food and water intake?
The effect of the delta-opioid antagonists ICI 154,129 (1-100 micrograms, i.c.v.) and ICI 174,864 (1-100 micrograms, i.c.v.) and of the delta-agonist D-Ala2-D-Leu5-enkephalin (DADL; 1-10 micrograms, i.c.v.) on the intake of food and water of non-deprived rats was investigated. Animals treated with either ICI 154,129 or ICI 174,864 ate and drank significantly less than vehicle-treated controls over a 3 hr test period. The suppressant effects of these peptides on appetite were similar to those observed with the more commonly-used opioid antagonists, naltrexone and Mr 2266. In contrast, the delta-agonist DADL produced an increase in both the consumption of food and water in the 3 hr following administration of drug. The findings presented in this study lend further support to the hypothesis that an endogenous enkephalin/delta-receptor system may play a role in the tonic induction of ingestive behaviour.
D000818:Animals; D001575:Benzomorphans / Q000494:pharmacology; D004327:Drinking Behavior / Q000502:physiology*; D004743:Enkephalin, Leucine / Q000031:analogs & derivatives / Q000494:pharmacology; D016308:Enkephalin, Leucine-2-Alanine; D005247:Feeding Behavior / Q000502:physiology*; D007274:Injections, Intraperitoneal; D007276:Injections, Intraventricular; D008297:Male; D009271:Naltrexone / Q000494:pharmacology; D051381:Rats; D011919:Rats, Inbred Strains; D011957:Receptors, Opioid / Q000502:physiology*; D017465:Receptors, Opioid, delta
D001575:Benzomorphans; D011957:Receptors, Opioid; D017465:Receptors, Opioid, delta; C027247:MR 2266; D004743:Enkephalin, Leucine; D009271:Naltrexone; D016308:Enkephalin, Leucine-2-Alanine; C036405:ICI 154129