A vagal gut-brain axis for feeding induced gastric secretion

Feeding begins with food-seeking and ends with nutrient absorption and waste elimination. Although meal-related sensory cues are known to shape feeding behavior, how they engage neural circuits to control digestion remains unclear. We dissected vagal gut-brain-gut pathways that mediate meal-induced gastric secretion. Vagal afferent neurons innervating the stomach were necessary and sufficient for secretion. Among those, Glp1r and Sst neurons robustly drove acid, pepsin, and gastrin secretion, whereas Oxtr and Vip neurons had little effect. Piezo2 was expressed in Glp1r mechanosensory afferents, and conditional deletion of Piezo channels attenuated distension-evoked secretion. On the efferent limb, genetically defined vagal motor neuron subsets differentially recruited secretory outputs: Cck neurons broadly increased acid, pepsin, and gastrin, whereas Grp neurons preferentially drove acid secretion. Finally, enteric circuit dissection revealed modular output control: Calb2 enteric neurons potently drove secretion with minimal motility effects, Grp enteric neurons coupled secretion to motility, and Cysltr2 enteric neurons selectively modulated acid output. Together, these results define a cell-type resolved vagal-enteric architecture for gastric control and show that secretory and motor programs can be segregated across dedicated enteric neuron subtypes.