Vagal innervation of the stomach reassessed: brain-gut connectome uses smart terminals.
Level 5 - mechanism / opinion, no new human data
Narrative review of neuroanatomical and morphological mechanisms without new empirical human data.
PubMed 31268562 · doi:10.1111/nyas.14138
What was done
This narrative review synthesized recent morphological observations regarding autonomic and vagal innervation of the stomach and gastrointestinal tract to explain how brain-gut communication operates despite a numerical disparity between vagal axons and intrinsic enteric neurons.
What was found
The abstract notes that afferents account for approximately 80% of vagal neurites. Despite the vagus containing thousands of axons relative to millions of enteric neurons, terminal arbors are extensive, regionally specialized, polymorphic, polytopic, and polymodal with multiple receptor types ("smart terminals"). These morphological specializations provide one-to-many efferent projections and many-to-one afferent convergences, enabling complex peripheral integration. No additional quantitative data were reported.
Why it matters
Recognizing that vagal terminals perform peripheral signal integration clarifies the functional architecture of the brain-gut connectome and may guide the development of targeted neuromodulation therapies for gastrointestinal disorders.
Limits
This is a narrative review rather than an empirical trial or systematic review. The abstract does not provide quantitative effect measures, sample sizes, or specific experimental species details.
Cited by
- supports Approximately 80% of the fibers of the vagus nerve are sensory afferent fibers transmitting information from the body to the brain.