Vagal afferent signaling

Vagal afferent signaling refers to the collective transmission of sensory information from internal organs (notably the heart, gastrointestinal tract, lungs, pancreas, and liver) to the brain via the afferent fibers of the vagus nerve[1][2][3][5][9]. These sensory fibers outnumber motor (efferent) fibers in the vagus nerve by approximately 4:1 to 9:1, depending on the organ system, and play a central role in physiological homeostasis, including the regulation of heart rate, gastrointestinal motility and secretion, food intake, glucose metabolism, immune responses, and inflammatory signaling[1][3][4][6]. Sensory inputs are derived from diverse specialized endings (mechanosensors, chemosensors, stretch receptors) and utilize various neurotransmitters (e.g., glutamate) to relay information to brainstem nuclei, such as the nucleus tractus solitarius (NTS)[1][3][4]. The pathways exhibit functional plasticity in response to physiological status (e.g., feeding, obesity, inflammation) and are implicated in numerous diseases, but the term itself does not denote a discrete therapeutic target[2][4][5][10].

Other names

Vagal sensory signalingVagal sensory pathwayVagal afferent pathway

Mechanisms depend on individual receptors or channels within afferent fibers, e.g., GLP-1 receptor agonism, serotonin receptor modulation, glutamatergic signaling modulation.