Fig. 3

Schematic of the nervous reflex involving neural glucose sensing that controls pancreatic secretion. Glucose in the oral cavity and in the hepatoportal vein area induces pancreatic secretion by mechanisms that integrate afferent nerves that project from the taste buds and the hepatoportal vein to the brainstem and hypothalamus and efferent nerves from these areas to the pancreas. Green lines: parasympathetic innervation (via release of the neurotransmitters ACh, VIP, PACAP, GRP); Red lines: sympathetic innervation (via release of the neurotransmitters NE, NPY, galanin)