<P> The myenteric plexus originates in the medulla oblongata as a collection of neurons from the ventral part of the brain stem . The vagus nerve then carries the axons to their destination in the gastrointestinal tract . </P> <P> They contain Dogiel cells . </P> <P> The myenteric plexus functions as a part of the enteric nervous system (digestive system). The enteric nervous system can and does function autonomously, but normal digestive function requires communication links between this intrinsic system and the central nervous system . The ENS contains sensory receptors, primary afferent neurons, interneurons, and motor neurons . The events that are controlled, at least in part, by the ENS are multiple and include motor activity, secretion, absorption, blood flow, and interaction with other organs such as the gallbladder or pancreas . These links take the form of parasympathetic and sympathetic fibers that connect either the central and enteric nervous systems or connect the central nervous system directly with the digestive tract . Through these cross connections, the gut can provide sensory information to the CNS, and the CNS can affect gastrointestinal function . Connection to the central nervous system also means that signals from outside of the digestive system can be relayed to the digestive system: for instance, the sight of appealing food stimulates secretion in the stomach . </P> <P> The enteric nervous system makes use of over 30 different neurotransmitters, most similar to those of the CNS such as acetylcholine, dopamine, and serotonin . More than 90% of the body's serotonin lies in the gut; as well as about 50% of the body's dopamine, which is currently being studied to further our understanding of its utility in the brain . The heavily studied neuropeptide known as substance P is present in significant levels and may help facilitate the production of saliva, smooth muscle contractions, and other tissue responses . </P>

Which nerve plexus plays a role in peristalsis