Inhibitory neurotransmission regulates vagal efferent activity and gastric motility.
The gastrointestinal tract receives extrinsic innervation from both the sympathetic and parasympathetic nervous systems, which regulate and modulate the function of the intrinsic (enteric) nervous system. The stomach and upper gastrointestinal tract in particular are heavily influenced by the parasympathetic nervous system, supplied by the vagus nerve, and disruption of vagal sensory or motor functions results in disorganized motility patterns, disrupted receptive relaxation and accommodation, and delayed gastric emptying, amongst others. Studies from several laboratories have shown that the activity of vagal efferent motoneurons innervating the upper GI tract is inhibited tonically by GABAergic synaptic inputs from the adjacent nucleus tractus solitarius. Disruption of this influential central GABA input impacts vagal efferent output, hence gastric functions, significantly. The purpose of this review is to describe the development, physiology, and pathophysiology of this functionally dominant inhibitory synapse and its role in regulating vagally determined gastric functions.
Department of Neural and Behavioral Sciences, Penn State College of Medicine, Hershey, PA 17033, USA.
Caitlin A
CA
McMenamin
Department of Neural and Behavioral Sciences, Penn State College of Medicine, Hershey, PA 17033, USA.
R Alberto
RA
Travagli
Department of Neural and Behavioral Sciences, Penn State College of Medicine, Hershey, PA 17033, USA knb13@psu.edu.
Kirsteen N
KN
Browning
D000818:Animals; D018682:GABA Agents; D005769:Gastrointestinal Motility; D006801:Humans; D017552:Solitary Nucleus / Q000502:physiology; D013270:Stomach / Q000502:physiology*; D009435:Synaptic Transmission; D014630:Vagus Nerve / Q000502:physiology*
D018682:GABA Agents
DMV; GABAergic signaling; Inhibitory neurotransmission; NTS; gastric motility; vagus