Mechanism of Effect Opioid Central Food Intake Regulation in Ad LibitumFedNeonatalLayer-Type Chicken

Subject Areas :

Mohammad Shojaei ¹ , Morteza Zendehdel ² , Vahhab Babapour ³ , Saeed Charkhkar ⁴ , Saeed Rasoulinejad ⁵

1 - دانش آموخته دکتری تخصصی فیزیولوژی بخش فیزیولوژی گروه علوم پایه دانشکده دامپزشکی، واحد علوم و تحقیقات تهران، دانشگاه آزاد اسلامی،تهران، تهران. ایران
2 - دانشیار بخش فیزیولوژی گروه علوم پایه دانشکده دامپزشکی دانشگاه تهران، تهران. ایران
3 - استاد بخش فیزیولوژی گروه علوم پایه دانشکده دامپزشکی دانشگاه تهران، تهران. ایران.
4 - استادیار بخش بهداشت و بیماری های طیور،گروه علوم درمانگاهی دانشکده دامپزشکی، واحد علوم و تحقیقات تهران، دانشگاه آزاد اسلامی، تهران.ایران.
5 - گروه زیست شناسی، واحد رودهن، دانشگاه آزاد اسلامی، تهران. ایران.

Received: 2017-10-03 Accepted : 2018-08-04 Published : 2017-10-23

Keywords: Opioidergic, food intake, Layer-Type Chicks,

Abstract :

Inroduction & Objective:Opioidergic system has crucial role on central regulation of food intake in mammals and birds. This study was designed to investigate role of opioidergic system on opioid-induced feeding behavior in 3-h food-deprived (FD3) neonatal layer-type chicks.Material and Methods:144 chickens allocated into3 experiments, each with four treatment groups. In Experiment 1, birds were ICV injected with D-Ala2–NMe-Phe4-Glyol5-enkephalin (DAMGO, µ-opioid receptor agonist) (125, 250 and 500pmol). In Experiment 2, chickens were ICV treated with D-Pen2,5Enkephalin,D-Pen2,D-Pen5Enkephalin (DPDPE, δ-opioid receptor agonist) (20, 40 and 80pmol). In Experiment 3, the effect of ICV injection of U-50488H -, κ opioid receptor agonist (10, 20 and 30nmol) was investigated in chicks.Cumulative food intake recorded until 3-h post injection.Results: According to the results, ICV injection of µ-opioid receptor agonist significantly diminished food intake (P≤0.05). Also, injection of δ and κ-opioid receptors agonist significantly increased food intake (P≤0.05). ICV injection of DAMGO significantly decreased food intake whereas DPDPE and U-50488H  increased food intake (P≤0.05). Conclusion: These results suggest that central opioidergic system has important role on feeding behavior.