Function of neurons in the gastrointestinal tract Neurogastroenterology

1 function of neurons in gastrointestinal tract

1.1 peristaltic reflex
1.2 segmentation
1.3 secretion

function of neurons in gastrointestinal tract

a simplified image showing peristalsis


the peristaltic reflex

peristalsis series of radially symmetrical contractions , relaxations of muscles propagate down muscular tube. in humans , other mammals, peristalsis found in smooth muscles of digestive tract propel contents through digestive system. word derived new latin , comes greek peristallein, wrap around, peri-, around + stallein, place . peristalsis discovered in 1899 work of physiologists william bayliss , ernest starling. working on small intestines of dogs, found response of increasing pressure in intestine caused contraction of muscle wall above point of stimulation , relaxation of muscle wall below point of stimulation.

segmentation

segmentation contractions contractions in intestines carried out smooth muscle walls. unlike peristalsis, involves contraction , relaxation of muscles in 1 direction, segmentation occurs simultaneously in both directions circular muscles alternatively contract. allows thorough mixing of intestinal contents, known chyme, allow greater absorption.

secretion

the secretion of gastrointestinal enzymes, such gastrin , secretin, regulated through cholinergic neurons residing in walls of digestive tract. hormone secretion controlled vagovagal reflex, neurons in digestive tract communicate through both afferent , efferent pathways vagus nerve.