GABAA Receptors Mediate Anxiety-like Behavior Induced by Ghrelin in Neonatal Chick Forebrain

GASTÓN MS; SALVATIERRA NA

Huerta Grande, Cordoba

Congreso; XXVII Congreso Anual Sociedad Argentina de Neurociencias; 2012

Sociedad Argentina de Neurociencias

Ghrelin is a 28 aa peptide with homology between species and has an anxiogenic action in rodents and birds. The GABAergic system is modulated by stressful events that modulate the synaptic transmission and strength. In chicks, has been identified a high density of GABAAR in the intermediate medial hyperstriatum ventrale (IMHV), a telencephalic area that is crucially involved in the process of imprinting. In the present study, we evaluated the involvement of GABAAR in the anxiogenic-like effect of ghrelin. In the first experiment, bilateral injections of ghrelin into the IMHV significantly increased the latency to ambulate in an Open Field test in a dose-dependent manner (15-900pmol) compared to saline control, indicating an anxiogenic action. In the second experiment, the ip injection of 0.036 and 0.36 mg/kg of bicuculline (antagonist) blocked the response induced by ghrelin (30pmol) on anxiety-like behavior in the Open Field test. These results demonstrate for the first time the participation of GABAAR in anxiogenic action of ghrelin. In addition, IMHV, an area strongly involved in processing memory, also plays a central role in the expression of stress-related behaviors