Intracerebroventricular injection of mammalian and chicken glucagon-like peptide-1 inhibits food intake of the neonatal chick.

Glucagon-like peptide-1 (GLP-1), structurally similar to glucagon, is synthesized from a larger precursor, preproglucagon, and has been postulated to be a novel incretin. Recently, it was reported that central administration of GLP-1 decreased food intake in rats. The amino acid sequences of GLP-1 are identical in all mammals, and chicken GLP-1 exhibits a high homology with mammalian GLP-1. The aim of this study was to elucidate whether central injection of mammalian or chicken GLP-1 inhibits food intake in the chick, and to compare their effects. Intracerebroventricular administration of mammalian and chicken GLP-1 strongly inhibited food intake of chicks. However, the suppressive effect of both GLP-1 on food intake was similar. These results show that GLP-1 with a variety of amino acid sequences may be the most potent inhibitor of food intake in the chicken.