ENDOCRINE TASTE RECEPTORS. “The taste buds also serve as endocrine organs and secrete regulatory hormones in response to nutrient stimulation, including glucagon like peptide (GLP-1) and glucagon, among other endocrine peptides.” These digestive hormones in turn signal organs like the pancreas to prepare to secrete insulin in response to the increase in blood glucose.
http://www.sciencedirect.com/science/article/pii/S0960982213004181