Recently, the suppressive effect on food intake by the central administration of glucagon-like peptide-1 (GLP-1) has been confirmed in both rats and chicks. The importance of the N-terminal amino acid, histidine, for the bioactivity of GLP-1(7-36) in the central nervous system was suggested, though the role for C-terminal amino acids in the central nervous system has not been reported. The present study was done to elucidate the central effect of N-terminal fragments of GLP-1(7-36) on food intake of the neonatal chick. Intracerebroventricular (i.c.v.) administration of mammalian GLP-1(7-36) inhibited food intake of chicks, but the fragments of GLP-1(7-16) and GLP- 1(7-26) did not show the suppressive effect on food intake. Furthermore, the extended fragments, GLP-1(7-30) and GLP-1(7-33), also had no effects on food intake. It is concluded that C-terminal amino acids of GLP-1(7-36) have an important role for the bioactivity in the central nervous system with special reference to feeding behavior.
All Science Journal Classification (ASJC) codes
- Molecular Biology
- Clinical Neurology
- Developmental Biology