Mapping of Glucagon-like Peptide-1 Receptor Expression in the Developing Mouse Brain

Studying the role of glucagon-like peptide-1 (GLP-1) and GLP-1 receptor (GLP-1R) in the mouse brain has been a subject of emergent relevance in recent years due to its presence in the central and peripheral nervous systems, as well as the gut. Previous examination of GLP-1R location in the adult mouse brain has been widely beneficial, however the ontogeny of GLP-1R in the developing mouse brain has not been thoroughly observed. I examined the pattern of expression of Glp1rmRNA in the central nervous system using in-situ hybridization across multiple stages of mouse development, embryonic and postnatal. Glp1rmRNA expression was found across all ages in the hippocampus, lateral septum, medial septal nucleus, amygdala, bed nucleus of the stria terminalis, thalamus, nucleus accumbens, cerebral cortex, caudate putamen, regions of the midbrain, and hypothalamus. Embryonic brains displayed higher and more widespread expression than postnatal brains, which could signify the importance of GLP-1R during development. Early postnatal expression of Glp1rmRNA was more restricted than embryonic patterns, but still expressed in specific brain regions and circuits not found in adult expression patterns, including the medial septal nucleus, thalamus and somatosensory cortex. These data contribute to the study of GLP-1R development in the mouse brain, the investigation of treatment of mood disorders, diabetes and obesity with GLP-1R agonists, and possible further implications to treat pregnant women that have these diseases.