Figure 1.
Peripheral signals of sense of satiety, after gastric distension, reach the nucleus of the solitary tract/area prostrema complex (NTS/AP) via afferent vagal nerves (green line). The NTS projects to the dorsal motor nucleus (DMN). This pathway modulates glucose production, gastrointestinal motility and hormone release (cholecystokinin, CCK; peptide YY, PYY; glucagon-like peptide-1, GLP-1), and pancreatic secretion via efferent vagal nerves (light blue line). The suggested site of action of vagal nerve stimulation (VNS) is indicated by the dotted purple lines, while the mechanism of weight loss hypothesized vagal nerve blockade (VBLOC) includes a decrease in gastric emptying and inhibition of pancreatic exocrine secretion (dotted red lines) [5].