Local reflex and long reflexSympatheticParasympatheticToprevertebralganglia,spinal(mainlypostganglionic)(preganglionic)cord,andbrainstemMventericplexusSubmucosalplexusSensoryneuronsEpitheliumUuUuUUuuUuuu0Hall:Guyton and HallTextbookofMedical Physiology,1ZthEditionCopyright2011bySaunders,animprintofEisevier,Inc.Allrightsreserved
Local reflex and long reflex
(1)ExtrinsicnervoussystemSympathetic nerveParasympathetic nerve↓pelvic nerveNEAch↓↓β2M↓1+Glmotility,↑GI motility,↓Gland secretionGland secretionGl smooth muscleL
(1) Extrinsic nervous system Parasympathetic nerve pelvic nerve Sympathetic nerve Ach M ↑GI motility, ↑Gland secretion, ↓GI smooth muscle NE β2 ↓ GI motility, ↓ Gland secretion
(2) Enteric nervous systemVeinSubmucosalplexusMesentery(plexusofMeissner)ArteryGlandsinsubmucosaNerveSubmucosaGland inmucosaDuct of glandoutsidetractMyentericplexusLymphatictissueSerosa:LumenAreolarconnectivetissueEpitheliumMucosa:Muscularis:EpitheliumCircularmuscleLaminapropriaLongitudinal muscleMuscularismucosae
(2) Enteric nervous system
LONGITUDINALmuscleSEROSAMYENTERICplexusCIRCULARmuscleSUBMUCOSALplexusMUCOSAActivationofSUBMUCOSALPLEXUSActivationofMYENTERICPLEXUSincreasessecretoryactivityincreasestoniccontractionmodulatesintestinalabsorptionincreases intensityofrythmic contractionsincreasesrateofrythmiccontractionsincreasesvelocityofconduction- Submucous plexus: regulate gastrointestinal blood flowand control Gl secretion-Myenteric plexus: control over Gl motility
– Myenteric plexus: control over GI motility – Submucous plexus: regulate gastrointestinal blood flow and control GI secretion
CopyrightTheMcGraw-Hill Companies, Inc.Permission required for reproduction or display.Emotionalstates/HungerSight, smell,Centralnervoussystemtaste of foodLongEfferentAfferentreflexesneuronsautonomicneuronsGastrointestinalwallsSmoothChemoreceptors,Nervemuscleosmoreceptors,orplexusorglandmechanoreceptorsShortreflexesGastrointestinal lumenStimulusResponseTheentericnervous systemcoordinatesdigestion,secretion,and motilitytooptimizenutrientabsorption.Itsactivityismodified byinformationfromtheCNSandfromlocalchemicalandmechanicalsensors
The enteric nervous system coordinates digestion, secretion, and motility to optimize nutrient absorption. Its activity is modified by information from the CNS and from local chemical and mechanical sensors