M Jelokhani - Department of Basic Sciences, Faculty of Veterinary Medicine, Science and Research Branch, Islamic Azad University, Tehran, Iran
B Vazir - Department of Basic Sciences, Faculty of Veterinary Medicine, Science and Research Branch, Islamic Azad University, Tehran, Iran
M Zendehdel - Department of Basic Sciences, Faculty of Veterinary Medicine, University of Tehran, Tehran, Iran
A Jahandideh - Department of Clinical Sciences, Faculty of Veterinary Medicine, Science and Research Branch, Islamic Azad University, Tehran, Iran

This study aimed to assess the possible feeding behavior alterations by central interactions of cholecystokinin (CCK) and glutamatergic systems in neonatal chickens. In experiment ۱, chickens received intracerebroventricular (ICV) administration of saline and CCK (CCK۴; ۰.۲۵, ۰.۵, and ۱ nmol). In experiment ۲, birds were ICV injected with saline, CCK۸s (۰.۲۵, ۰.۵, and ۱ nmol). In experiment ۳, chickens received the ICV injection of saline, CCK۸s (۱ nmol), MK-۸۰۱ (۱۵ nmol), and co-injection of the CCk۸s+MK-۸۰۱. Experiments ۴-۷ were performed similar to experiment ۳, except for chickens that were injected with CNQX (۳۹۰ nmol), AIDA (۲ nmol), LY۳۴۱۴۹۵ (۱۵۰ nmol), and UBP۱۱۱۲ (۲ nmol) instead of MK-۸۰۱. Subsequently, the total amount of the consumed food was determined. According to the results, the ICV administration of CCK۴ (۰.۲۵, ۰.۵, and ۱ nmol) could not affect the food intake in chickens (P>۰.۰۵). The ICV injection of the CCK۸s (۰.۲۵, ۰.۵, and ۱ nmol) led to a dose-dependent hypophagia (P<۰.۰۵). Moreover, hypophagia induced by CCK۸s decreased by the co-injection of the CCK۸s+MK-۸۰۱ (P<۰.۰۵). These results showed that the hypophagic effects of the CCK on food intake can be mediated by NMDA glutamate receptors in layer-type chickens.

chickens, Cholecystokinin, Food intake, Glutamatergic