Vagal innervation of the stomach reassessed: brain−gut connectome uses smart terminals. Issue 1 (3rd July 2019)

• Record Type: Journal Article
• Authors: Powley, Terry L.; Jaffey, Deborah M.; McAdams, Jennifer; Baronowsky, Elizabeth A.; Black, Diana; Chesney, Logan; Evans, Charlene; Phillips, Robert J.
• Is Part Of: Annals of the New York Academy of Sciences. Volume 1454:Issue 1(2019)
• Page Start: 14
• Page End: 30
• Publication Date: 2019-07-03
• Subjects: afferent -- autonomic -- efferent -- intestines -- parasympathetic -- postganglionic -- preganglionic -- stomach -- viscera -- visceral afferent -- vagus; Medical sciences -- Periodicals; Medicine -- Periodicals; Science -- Periodicals; 610
• DOI: 10.1111/nyas.14138
• Languages: English
• ISSNs: 0077-8923

Abstract

Abstract: Brain−gut neural communications have long been considered limited because of conspicuous numerical mismatches. The vagus, the parasympathetic nerve connecting brain and gut, contains thousands of axons, whereas the gastrointestinal (GI) tract contains millions of intrinsic neurons in local plexuses. The numerical paradox was initially recognized in terms of efferent projections, but the number of afferents, which comprise the majority (≈ 80%) of neurites in the vagus, is also relatively small. The present survey of recent morphological observations suggests that vagal terminals, and more generally autonomic and visceral afferent arbors in the stomach as well as throughout the gut, elaborate arbors that are extensive, regionally specialized, polymorphic, polytopic, and polymodal, commonly with multiplicities of receptors and binding sites—smart terminals. The morphological specializations and dynamic tuning of one‐to‐many efferent projections and many‐to‐one convergences of contacts onto afferents create a complex architecture capable of extensive peripheral integration in the brain−gut connectome and offset many of the disparities between axon and target numbers. Appreciating this complex architecture can help in the design of therapies for GI disorders. Abstract : In this short review, we examine and illustrate some of the recent observations that have supported the conclusion that autonomic, and specifically vagal, efferents and visceral afferents from the nodose ganglia establish, respectively, one‐to‐many and many‐to‐one connections to create the brain−gut connectome.