Enteric nervous system
The enteric nervous system ( ENS for short , enteric from ancient Greek το ἔντερον (enteron) for intestine ; also intestinal nervous system , intestinal wall nervous system , visceral nervous system or intramural nervous system , colloquially also abdominal brain, abdominal brain or intestinal brain) is part of the nervous system .
description
The enteric nervous system consists of a complex network of nerve cells (neurons) that run through almost the entire gastrointestinal tract . In humans, it has four to five times more neurons than the spinal cord (around 100 million nerve cells). This independent nervous system is located as a thin layer between the muscles of the digestive system. Its task is z. B. to control digestion . It can work completely autonomously, but is subject to the influences of the sympathetic and parasympathetic nervous system in order to harmonize with the entire organism. Within the ENS one finds neurotransmitters z. B. Serotonin and dopamine (excitatory) and NO and vasoactive intestinal peptide (inhibitory).
The ENS has a strong influence on the digestive process and well-being. Among other things, it regulates:
- the intestinal motility
- the ion transport associated with secretion and absorption
- the gastrointestinal blood flow
- the immunological functions of the gastrointestinal tract.
The main components of the ENS are two nerve plexuses that are embedded in the intestinal wall :
- the myenteric plexus ( Auerbach's plexus ) between the circular and longitudinal muscle layers
- the submucosal plexus ( Meissner's plexus ) in the submucosa .
In addition, there are other smaller plexuses of the ENS directly below the tunica serosa , within the circular muscles and in the mucous membrane itself. In addition to the neurons in the real sense, there are also the interstitial cells of Cajal (Cajal cells). These are specialized muscle cells that can trigger contractions of the muscles immediately adjacent to them completely independently of neurons, and thus represent a kind of pacemaker system that can be compared in the broadest sense with the autonomous pacemaker system of the heart.
Some scientists suspect that the exchange of information between the enteric nervous system and the brain also plays a role in intuitive decisions (“gut decisions”).
Diseases
A disorder of the enteric nervous system is the clinical picture of Hirschsprung's disease . This disease is characterized by the (segmental) absence of ganglion cells ( aganglionosis ) of the submucosal and myenteric plexus.
Web links
- Manuela Lißina-Krause: TRMreport_01: New nerves for the intestine - one topic, two perspectives , Informationsdienst Wissenschaft e. V.
Individual evidence
- ↑ Hermann Triepel , Robert Herrlinger : The anatomical names. Your derivation and pronunciation. 26th edition. J. F. Bergmann, Munich 1962, pp. 30 and 79.
- ↑ Renate Lüllmann-Rauch: Histology . 2nd Edition. Thieme, Stuttgart 2006, ISBN 3-13-129242-3 .
- ↑ Michael Gershon: The Smart Belly. The discovery of the second brain . Goldmann, Munich 2001, ISBN 3-442-15114-7 .
- ↑ geo.de: Neurology: How the stomach determines the head