Adrenomedullin reduces food intake through interactions with satiety‐related hypothalamic nuclei in chicks

Adrenomedullin (AM) is a 57‐residue peptide that reduces food intake (FI) in mammals, although central pathways mediating this effect are poorly understood. Thus, this study was designed to test the hypothesis that AM reduces FI through interactions with hypothalamic nuclei associated with satiety perception. Because AM had not been tested in aves, we demonstrated that AM‐treated chicks reduced FI at all doses tested with a 30% reduction in FI 30 min post‐injection sustaining through 180 min, at which time cumulative FI was reduced to 20%. c‐Fos immunoreactivity was used to indicate neuronal activity in the hypothalamus; AM‐treated chicks had increased c‐Fos expression in the dorsomedial nucleus, ventromedial hypothalamus, and paraventricular nucleus (PVN), three nuclei associated with satiety perception, supporting our hypothesis. Because the PVN is dense with corticotrophin‐releasing hormone (CRH) receptors and CRH is a potent satiety inducer, we hypothesized AM may mediate its effect via CRH. Because blockade of CRH receptors with astressin did not attenuate AM‐induced FI reduction, we rejected this hypothesis. These results may aid in developing anti‐eating and thus anti‐obesity strategies.