Role of Central Cannabinoidergic System on GhrelinInduced Hypophagia in LayerType Neonatal Chicken

Background: Feeding behavior is regulated via a complex network which interacts through diverse signals from central and peripheral tissues. OBJECTIVES: The main purpose of the current study was to determine the role of central cannabinoidergic (CBergic) system on ghrelininduced hypophagia in 3h food deprived (FD3) neonatal chicken. METHODS: In experiment 1, chicks were ICV injected with control solution, ghrelin (0.6 nmol), SR141716A (selective CB1 receptors antagonist, 6.25 µg) and ghrelin + SR141716A. In experiment 2, chickens received ICV injection of (A) control solution, ghrelin (0.6 nmol), AM630 (selective CB2 receptors antagonist, 1.25 µg) and ghrelin + AM630. In experiment 3, chickens were ICV injected with control solution, 2AG (selective CB1 receptors agonist, 2µg), GSK1614343 (selective ghrelin receptors antagonist, 6 nmol) and 2AG + GSK1614343. In experiment 4, the birds received control solution, CB65 (selective CB2 receptors agonist, 6.25 µg), CB65 + GSK1614343. Then the cumulative food intake was measured until 120 min post injection. RESULTS: According to the results, ICV injection of the ghrelin, significantly decreased cumulative food intake (P lt;0.05). Coinjection of the ghrelin + SR141716A and/or ghrelin + AM630 significantly amplified ghrelininduced hypophagia compared to control group (P lt;0.05). Hyperphagia observed by ICV injection of the 2AG (2 µg) (P lt;0.05). Coinjection of the 2AG + GSK1614343 increased food intake compared to control group (P lt;0.05). ICV injection of the CB65 (1.25 µg) significantly increased food intake (P lt;0.05). Also, coinjection of the CB65 + GSK1614343 significantly amplified cumulative food intake in FD3 neonatal layertype chicken (P lt;0.05). CONCLUSIONS: These results suggested ghrelininduced hypophagia mediates via CB1 and CB2 receptors in neonatal layertype chicken