SEARCH · PubMed Health

Results for “MYENTERIC PLEXUS”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 1,009 records · Page 56Linked to original sources

PubMed1991

Localization of GAD-like immunoreactivity in the pancreas and stomach of the rat and mouse.

The aim of this study was to localize cells immunoreactive for glutamate decarboxylase (GAD), the enzyme of GABA synthesis, in pyloric and oxyntic regions of the rat stomach as well as in the rat and mouse pancreas. GAD immunocytochemistry was carried out on polyethylene glycol or cryostat sections of alkaline paraformaldehyde fixed tissue, with simultaneous immunolabelling of various gastro-pancreatic hormones for topographical comparison. In the rat stomach, nerve fibers displaying intense GAD-like immunoreactivity were seen in the myenteric plexus, the circular muscular layer, the submucosa and the lamina propria of the mucosa. But, they were absent from the submucous plexus. Colchicine treatment of the rats allowed to detect some labelled perikarya in the myenteric plexus suggesting that the GABAergic innervation is at least partly intrinsic to the stomach. In the oxyntic and pyloric mucosa, endocrine cells appeared immunostained for GAD. However, the nature of their hormones remained unknown since double immunodetections revealed that they were immunoreactive neither for gastrin nor for somatostatin. In the rat and mouse pancreas, GAD-like immunoreactivity was found in islet cells which corresponded only to insulin-secreting cells. Somatostatin-, glucagon- and pancreatic polypeptide-immunopositive cells were devoid of GAD immunolabelling. No GAD-like immunoreactivity was detected in the exocrine tissue and innervation. These results strenghten the hypothesis that GABA is not only a neurotransmitter in the stomach but that it could also be an endocrine or paracrine factor in the stomach and pancreas.

Animals↗

PubMed1987

The topography and dynamics of cholinergic transmission in the myenteric plexus-smooth muscle preparation of the guinea-pig ileum; the effect of ketocyclazocine, a kappa opiate ligand.

Output of acetylcholine (ACh), neurogenic electromyogram (NEMG) and contractions of guinea-pig ileum preparations were studied during stimulation by high-frequency trains of impulses. Under control conditions the output of ACh per impulse after 2nd to 4th impulses during train stimulation (30 Hz) was higher by 20-40% than the level of ACh output during the first impulse. In the presence of ketocyclazocine (KTZ, 80 nmol x l-1) the output of ACh evoked by the first impulse was more effectively inhibited than that after impulses 2 to 4 so that the increase was higher (80-170%). NEMG, a direct consequence of the localized action of released transmitter (ACh), was recorded in the longitudinal muscle 4 and 10 mm aborally from the focal stimulation site. The incidence of NEMG responses was higher at the proximal than at the distal site and was proportional to the number of impulses in a train (100 Hz). At the distal site KTZ suppressed the appearance of NEMG responses to single impulses whereas at the proximal site its effect was much less; and so was its effect at either site during train stimulation. It is concluded that in the course of train stimulation, sites of transmission more distant from the stimulation focus were recruited, and consequently the secretion of ACh in succeeding impulses was enhanced. KTZ might preferentially inhibit the propagation of excitation by the very first impulse.

Acetylcholine↗

PubMed1999

Interstitial cells of Cajal in the human fetal small bowel as shown by c-kit immunohistochemistry.

BACKGROUND: Interstitial cells of Cajal (ICCs) express the tyrosine kinase receptor c-kit, which is required for their development and spontaneous pacemaker activity in the bowel. From murine models it has been proposed that ICCs do not develop until after birth, but more recent findings indicate that c-kit is expressed early in the embryonic period. The temporal development of ICCs in the human gut remains unknown. AIM: To investigate ICCs in the human fetal small bowel using c-kit immunohistochemistry. SUBJECTS: Small bowel specimens were obtained at post mortem examination of 16 fetuses and nine neonates, eight of whom were premature, born at gestational ages of 13 to 41 weeks, without gastrointestinal disorders. METHODS: Immunohistochemical analysis was performed on material fixed in formalin and embedded in paraffin. The specimens were exposed to antibodies raised against c-kit (an ICC marker) and neurone specific enolase (a general neuronal marker). The ABC complex method was used to visualise binding of antibodies to the corresponding antigens. RESULTS: c-kit immunoreactive cells were visualised from 13 weeks of gestation. The immunoreactivity was mainly localised in association with the myenteric plexus. From about 17-18 weeks of gestation, the ICCs formed a layer along the myenteric plexus, whereas this layer appeared to be disrupted at 13-16 weeks of gestation. CONCLUSIONS ICCs are c-kit immunoreactive at least from a gestational age of 13 weeks in the human fetal small intestine. From 17-18 weeks of gestation until birth, they form a continuous layer around the myenteric ganglia.

Embryonic and Fetal Development↗

PubMed1986

Distribution and characterization of the opioid octapeptide met5-enkephalin-arg6-gly7-leu8 in the gastrointestinal tract of the rat.

The distribution and characterization of the opioid octapeptide met5-enkephalin-arg6-gly7-leu8 (met5-enk-arg6-gly7-leu8) within the gastrointestinal tract of the rat has been determined by immunohistochemistry and radioimmunoassay by use of a newly developed antibody to met5-enk-arg6-gly7-leu8. With both techniques, met5-enk-arg6-gly7-leu8-immunoreactivity (met5-enk-arg6-gly7-leu8-IR) was detected in all regions of the gastrointestinal (GI) tract except the esophagus. The highest concentration of immunoreactive met5-enk-arg6-gly7-leu8 was observed in the colon, while intermediate concentrations were found in the stomach, duodenum, jejunum, and ileum. Immunostained somata were observed chiefly in the myenteric plexus; immunostained processes were present primarily in the myenteric plexus and the circular muscle layer. This distribution pattern is similar to that previously observed with antiserum to met5-enkephalin-arg6-phe7 (met5-enk-arg6-phe7). Chromatographic analysis of met5-enk-arg6-gly7-leu8-immunoreactive peptides extracted from the GI tract revealed the presence of an immunoreactive peptide of high molecular weight which accounted for approximately three-quarters of met5-enk-arg6-gly7-leu8-IR in both stomach and colon. These findings suggest a role for peptides related to the octapeptide met5-enk-arg6-gly7-leu8 in the regulation of GI function.

Animals↗

PubMed2003

Eosinophilic myenteric ganglionitis is associated with functional intestinal obstruction.

The diagnostic features and clinical course of three children (aged 1 month to 15 years) with severe functional intestinal obstruction and inflammation of the colonic lamina propria and myenteric plexus are described. The myenteric inflammatory infiltrate was eosinophil predominant with none of the immunological characteristics of lymphocytic ganglionitis. Neurones in the myenteric ganglia expressed the potent eosinophil chemoattractant interleukin 5. None responded to dietary exclusion but all three responded symptomatically to immunosuppression/anti-inflammatory treatments. Eosinophilic ganglionitis is associated with a pseudo-obstructive syndrome which is amenable to anti-inflammatory treatment.

Adolescent↗

PubMed2002

Smooth muscle, neurons and interstitial cells of guinea pig ileum: are there tachykinin neurokinin 1 receptor subtypes?

Binding and autoradiographic studies were carried out in guinea pig ileum to examine neurokinin (NK) 1 receptor location and subtypes using the NK-1-selective radioligand [(125)I]Bolton-Hunter[Sar(9),Met(O(2))(11)]SP. Two membrane preparations were made: (1) longitudinal muscle containing the myenteric plexus and (2) circular muscle containing the interstitial cells of Cajal. In saturation binding studies, the K(D) was estimated as 1.3 and 1.0 nmol/l in each preparation, respectively. In competition binding, the rank order of potency was similar in both membrane preparations: SR140333 approximately CP99994 > or = [Sar(9),Met(O(2))(11)]SP approximately physalaemin approximately CP96345 (pIC(50) 9.5-8.7) >> neuropeptide gamma > or = septide (pIC(50) 7.8-7.4). Similarly, scyliorhinin I displayed equal affinity in both preparations, although binding was at two sites, of high affinity (pIC(50) 9.1, 30%) and low affinity (pIC(50) 7.2-6.6, 70%). The only competitor to bind differently in the two muscle preparations was scyliorhinin II, which bound to one site with low potency in the circular muscle (pIC(50) 6.9) but to high-affinity (pIC(50) 9.0, 17%) and low-affinity (pIC(50) 6.7, 83%) sites in the longitudinal muscle. In autoradiographic studies, dense specific binding was associated with the myenteric plexus and the inner circular muscle containing the interstitial cells of Cajal, with minimal specific binding to longitudinal and circular smooth muscle. These results suggest that the NK-1 receptor on the interstitial cells and the myenteric plexus is similar. The apparently low numbers of binding sites on intestinal smooth muscle may be due to a low expression of the NK-1 receptor. Alternatively, the radioligand may not recognize the guinea pig ileum muscle NK-1 receptors due to possible minor differences in their sequence or glycosylation.

Animals↗

PubMed1998

Neural mediation of vasoactive intestinal polypeptide inhibitory effect on jejunal alanine absorption.

It was recently shown that vasoactive intestinal polypeptide (VIP) inhibits rat jejunal alanine absorption, an effect that was significantly reduced by vagotomy. This study assesses the role of capsaicin-sensitive primary afferents (CSPA) and the myenteric plexus in the inhibition of rat jejunal alanine absorption by VIP. Continuous intravenous infusion of VIP (11.2 ng . kg-1 . min-1) reduced alanine absorption by 60% in sham control rats and by 20% in rats neonatally treated with capsaicin (P < 0.01). In in vitro experiments, VIP decreased alanine uptake by jejunal strips isolated from sham control rats in a dose-dependent manner. In the presence of 40 nM VIP, alanine uptake by full-thickness jejunal strips was reduced by 54% in sham control rats and by 25% in rats neonatally treated with capsaicin (P < 0.001). On the other hand, VIP reduced alanine uptake by mucosal scrapings by 25% in sham rats compared with 9% reduction in neonatally treated rats. Chemical ablation of the extrinsic innervation and jejunal myenteric plexuses by pretreatment with benzalkonium chloride significantly (P < 0.001) reduced basal alanine absorption and the inhibitory effect of VIP. Moreover, incubation of intestinal strips with tetrodotoxin and atropine reduced significantly (P < 0.05) the inhibitory effect of VIP on alanine absorption. These data suggest that VIP exerts its inhibitory effect on alanine absorption through the CSPA fibers and the myenteric plexus. The neuronal circuitry of this inhibitory process may involve cholinergic muscarinic mechanisms.

Afferent Pathways↗

PubMed1992

Histochemical localization of nitric oxide-synthesizing neurons and vascular sites in the guinea-pig intestine.

Laminar preparations of fixed segments of the guinea-pig intestine were examined for nitric oxide synthase activity using reduced nicotinamide adenine dinucleotide phosphate and nitroblue tetrazolium salt as substrates. Under conditions specific for detecting nitric oxide synthase-related diaphorase activity, a subpopulation of neural elements in the myenteric plexus, deep muscular plexus and submucosa were intensely stained. Intensely stained nerve fibres were distributed throughout the meshworks of the myenteric plexus and its innervation of the circular muscle, and in the submucosa within Henle's plexus. Intensely stained nerve cells and their processes were evident in most myenteric ganglia but were rare in ganglia of Henle's plexus. Stained ganglion cells comprised types I, II and VI of the morphologically defined enteric nerve cells. Stained neural elements were increasingly prevalent within successively more caudal segments of the intestine. In addition to neuronal staining, arterioles of the submucosal vascular network displayed distinct, punctate patches of staining distributed over their surface. Perivascular nerve fibre staining was absent. These results show nitric oxide synthase activity to be present within neurons and fibres of the major enteric nerve layers and within submucosal blood vessels throughout the guinea-pig small and large intestine.

Amino Acid Oxidoreductases↗

PubMed1997

Hyperpolarizing effects of morphine, clonidine and 2-chloroadenosine in myenteric neurons associated with tolerance to morphine.

Chronic treatment of guinea pigs with morphine produces non-specific subsensitivity (tolerance) of the longitudinal smooth muscle myenteric plexus (LM/MP) preparation of the guinea pig ileum to morphine, clonidine and 2-chloroadenosine correlated with a partial depolarization of myenteric S neurons. The purpose of our investigation was to gain further evidence regarding the cellular mechanism of tolerance. Either morphine or placebo pellets were implanted s.c. in guinea pigs 7 days before the experiment. Subsensitivity was confirmed by a marked decrease of the inhibitory effect of 0.1 microM morphine and 0.3 microM clonidine on neurogenically induced twitches in longitudinal smooth muscle myenteric plexus preparations from the morphine-pretreated guinea pigs. Intracellular microelectrode recording established that only myenteric S neurons that were hyperpolarized by morphine exhibited the depolarized state (difference of 7.2 mV), which occurred without a change in the threshold for initiation of action potentials. S neurons that were hyperpolarized by superfusion with solution containing morphine, 0.1 microM, were acutely hyperpolarized an equivalent amount (6-8 mV) by clonidine, 0.3 microM, or 2-chloroadenosine, 0.1 microM. Morphine and clonidine, but not 2-chloroadenosine, reduced input resistance. The hyperpolarizations and changes in conductance were not different between tolerant and control preparations for any agonist. It is concluded that 1) the receptors for the three agonists are colocalized on selected S neurons, 2) the transduction process for the hyperpolarizing effect of 2-chloroadenosine is different than that for morphine and clonidine, 3) cross-tolerance among the agonists is not a function of altered receptors or signal transduction processes and 4) the depolarized state is associated with tolerance of myenteric S neurons.

2-Chloroadenosine↗

PubMed1994

Structural organization and neuropeptide distributions in the equine enteric nervous system: an immunohistochemical study using whole-mount preparations from the small intestine.

The architecture and neurochemistry of the enteric nervous system was studied by use of whole-mount preparations obtained by microdissection of the horse jejunum. A myenteric plexus and two plexuses within the submucosa were identified. The external submucosal plexus lying in the outermost region of the submucosa had both neural and vascular connections with the inner submucosal plexus situated closer to the mucosa. Counts of neurones stained for NADH-diaphorase demonstrated the wide variation in size, shape and neurone content of individual ganglia in both the external and internal submucosal plexuses. The average number of cells/ganglion was similar in each plexus (about 25 cells). Immunoreactivities for galanin, vasoactive intestinal peptide and neuropeptide Y were observed in nerve cell bodies and fibres of each of the plexuses. Immunoreactivity for substance P was extensive and strong in nerve fibres of all plexuses but was weaker in cell bodies of the submucosal neurones and absent in the cell bodies of the myenteric plexus. Comparative quantitative analysis of immunoreactive cell populations with total cell numbers (enzyme staining) was indicative of neuropeptide colocalization in the external submucosal plexus.

Animals↗

PubMed2006

Induction and recovery of colonic motility/defecatory disorders after extrinsic denervation of the colon and rectum in rats.

BACKGROUND: Anterior resection for rectal disease is associated with extrinsic autonomic denervation of the neorectum, which may influence the myenteric plexus, and subsequently the motility/defecatory status after operation. METHODS: A rat model with denervated neorectum was constructed. Colonic contractile activity in vivo, the amount of generic neuron marker (PGP 9.5) and nitric oxide synthase (NOS) were measured periodically. The responses of the muscle strip in each period to electrical field stimulation were evaluated using various neurotransmitters. RESULTS: In rats with denervated neorectum, giant migrating contractions (GMCs) of the distal colon, the number of fecal lumps per day and their small size, significantly increased in the early phase postoperatively, although both recovered in the late-phase period. The contractile response of the muscle strip of the denervated colon to acetylcholine was reduced throughout the period; however, contraction of the denervated colon under the addition of NO inhibitor (l-NAME) was enhanced significantly in the late-phase period, and recovered to the control level by atropine. Neuronal NOS, but not PGP 9.5 concentration, in the myenteric plexus at the distal denervated colon, significantly increased in the late-phase period. None of the above items differed from the control at other colonic portions throughout the period. CONCLUSIONS: Extrinsic autonomic denervation causes abnormal hyper-motility in the neorectum, which may be associated with multiple evacuations in the early phase postoperatively. Increased acetylcholine and the subsequent increase of neuronal NOS in the myenteric plexus may be an adaptive mechanism to compensate for such abnormal colonic motility after extrinsic denervation.

Animals↗

PubMed1995

Distribution of neurotensin-immunoreactive neurons in the digestive tract of the chicken.

The origin of the neurotensin-containing nerve fibers in the digestive tract of the chicken has been investigated with the use of colchicine and immunohistochemistry. Neurotensin-immunoreactive nerve fibers were found in the smooth muscle layers from the esophagus to the duodenum. Their density of distribution was very high in the esophagus and crop (maximum mean value: 1315/mm2 of sectional area in the lamina muscularis mucosae of the crop) and decreased progressively to the duodenum. Neurotensin-immunoreactive neuronal cell bodies were observed after colchicine treatment in the submucosal plexuses of the esophagus and crop and in the myenteric plexuses of the esophagus, crop, proventriculus and gizzard, and they extended varicose fibers. The number of neurotensin-immunoreactive cell bodies was high in the myenteric plexus of the gizzard (28.3 +/- 2.7/ganglion) but low in the plexuses of the esophagus, crop and proventriculus. Seven days after cutting the glossopharyngeal nerve and vagus nerve unilaterally, the number and extent of neurotensin-immunostained structures in the smooth muscle layers from the esophagus to the gizzard did not show any significant difference between operated and unoperated sides. These results indicate that in the chicken the great majority of neurotensin-immunoreactive enteric fibers originate in the intramural plexuses of the upper digestive wall and are mainly distributed to smooth muscle cells.

Animals↗

PubMed2002

Physiological study of interstitial cells of Cajal identified by vital staining.

Interstitial cells of Cajal (ICC) form networks that intercalate between the enteric nervous system and smooth muscle cells and play a fundamental role in the control of gastrointestinal motility by initiating rhythmic electrical activity. In this report, we used a method to examine the physiological and morphological properties of ICC in living, intact tissues. ACK2, an anti-Kit antibody, was conjugated to a fluorescent probe and used to identify individual ICC for intracellular electrical recordings, to record changes in intracellular calcium concentration using fluorescent dyes and for confocal microscopy. Cyclic changes in intracellular calcium concentration were recorded in ICC with a frequency similar to the electrical slow wave. In addition, injection of a fluorescent dye into single ICC enabled the three-dimensional reconstruction of single myenteric plexus ICC within the intact network. The data show that ICC in intact networks from the myenteric plexus region in living tissues in the guinea-pig antrum exhibit an electrical slow wave, and that intracellular calcium oscillates at a frequency similar to the slow wave.

Aniline Compounds↗

PubMed1987

Co-existence of the enkephalinergic system and the melanotropinergic system in the rat duodenum shown by immunohistochemistry.

The immunohistochemical distribution of alpha-melanotropin (alpha-MSH) and Met-enkephalin (Met-ENK) immunoreactivities in the rat duodenum was examined by using immunofluorescence microscopy. Alternately staining of adjacent frozen serial sections with specific antisera directed to alpha-MSH or Met-ENK revealed that within a subpopulation of myenteric plexus perikarya alpha-MSH immunostaining co-exists with that of Met-ENK. Some myenteric plexus nerve fibres also contain both Met-ENK and alpha-MSH immunoreactivity. These findings might indicate that the genes encoding for the precursors of melanotropins (the pro-opiomelanocortin precursor) and enkephalin (the pro-enkephalin precursor) are generated from a common, large and single ancestor gene which remained conserved during evolution in the rat enteric nervous system.

Animals↗

PubMed2004

Immature intrinsic nerve innervations of pyloric muscle in idiopathic hypertrophic pyloric stenosis.

BACKGROUND AND PURPOSE: Various etiologies have been suggested to be responsible for the development of idiopathic hypertrophic pyloric stenosis (IHPS) in the newborn. The purpose of this study was to determine the maturity of intrinsic nerves and nitrergic neurons in the pyloric muscle in IHPS. METHODS: Full thickness pyloric muscle specimens were obtained from 6 infants with IHPS with age ranging from 27 to 95 (mean 58) days old and subjected to immunohistochemical and double chemiluminescence staining for protein gene product 9.5 (PGP9.5) and neuronal nitric oxide synthase (nNOS). RESULTS: The results showed absence of myenteric plexus between the circular and longitudinal muscle layers in 2 patients, decrease in 1 patient, normal myenteric plexus in 1 patient, and absence of nNOS-containing neurons in 4 patients. All 6 patients had expression of markers for supporting nerve cells and myogenesis in the pyloric smooth muscle. CONCLUSIONS: These results suggest that absence or immaturity of intrinsic nerve and nNOS-containing neurons in the pyloric muscle is the cause of IHPS. The demonstrated lack of innervation or delayed innervation may be the responsible mechanism for the development of IHPS, but further study is needed to elucidate the pathogenesis.

Humans↗

PubMed1985

Enkephalin neurons in the guinea pig proximal colon: an immunocytochemical study using an antiserum to methionine-enkephalin-Arg6-Gly7-Leu8.

The distribution and structure of the neurons containing opioid peptide-like immunoreactivity (enkephalin neurons) in the antimesenteric border of the guinea pig proximal colon were immunocytochemically investigated using an antiserum for methionine-enkephalin-Arg6-Gly7-Leu8 (R-0171). Whole-mount preparations of the different layers of the intestine perfusion-fixed with Bouin's fluid were immunostained by peroxidase-antiperoxidase techniques. Immunopositive nerve fibers were apparent in the longitudinal muscle layer, myenteric plexus, circular muscle layer and submucosa. Immunopositive perikarya of the ganglionic cells were found in the myenteric plexus. A Golgi-type panoramic view was obtained in the intensely-immunostained enkephalin neurons. Distinct immunoreactivity was shown in the many Dogiel type 1 neurons, characterized by short broad processes (winglets or alulae) and one long axon-like process, as well as a few type 2, characterized by several tapering processes, and type 3 neurons, characterized by dendrite-like processes. Many twig-like processes originated from the free margin of the winglet of the enkephalin neurons (wing-ramuli). A part of them entered the intramuscular fasciculus, while the rest remained inside the ganglion. There were transitional forms between these wing-ramuli and the tapering processes of the type 2 neurons or the dendrite-like processes of the type 3 neurons. The axon-like processes sent out branches (axon-ramuli) along their courses or into the intramuscular fasciculus. At the origin of these axon-ramuli, there was a nodulous or humped swelling of the axon-like process (nodulus or crista). In the myenteric ganglion, the axon-ramuli formed varicose terminals. In the guinea pig proximal colon, many axon-like processes of the enkephalin neurons ran in the oral direction. This polarity of neuronic processes may have a functional significance in the neuronal control of the antiperistalsis.

Animals↗

PubMed1993

Projections of nerve cells from the duodenum to the sphincter of Oddi and gallbladder of the Australian possum.

BACKGROUND: This study investigated the existence of direct neural connections between the duodenum and the biliary tract in the Australian possum. METHODS: Retrogradely transported neuronal dyes, Fast Blue and Dil, were injected into the wall of the gallbladder and the sphincter of Oddi. The duodenum, biliary tract, and sympathetic and sensory ganglia were examined for the presence of labeled cell bodies. RESULTS: Two to 3 weeks after gallbladder injection, labeled nerve cell bodies were found in the myenteric plexus of the proximal duodenum but were rare in the duodenum distal to the sphincter of Oddi. No neurons were found in the submucous plexus. Labeled nerve cells were also found in the sphincter of Oddi. After injection of the sphincter, labeled neurons were in both the submucous and myenteric plexuses of the duodenum, on either side. Approximately one third of labeled myenteric neurons were immunoreactive for enkephalin. Labeled cell bodies were also in the coeliaco-mesenteric, nodose, and dorsal root ganglia after both gallbladder and sphincter injection. After a myotomy on the proximal duodenum, no neurons were labeled on the pyloric side of the lesion by subsequent sphincter injection of dye. CONCLUSIONS: Direct neural pathways connect the duodenum with the gallbladder and the sphincter of Oddi, and the sphincter with the gallbladder; this implies that enteric nerve circuits participate in coordinating duodenal and biliary functions.

Animals↗

PubMed2003

How to approach the ENS: various ways to analyse motility disorders in situ and in vitro.

Motility disorders of the human intestine are so variable that they cannot be diagnosed by just one technique. Their aetiology is obviously so varied that they have to be approached with a broad range of technical methods. These reach from the simple haematoxylin-stained section to the isolation of stem or precursor cells. In this study, various methods to investigate the enteric nervous system and its surrounding tissue are demonstrated. While sections from paraffin-embedded material or cryostat sections provide only a two-dimensional perspective of the ENS, the whole-mount method yields three-dimensional perspectives of large areas of the gut wall. The three-dimensional impression can even be enhanced by electron microscopy of the isolated ENS. Dynamical aspects of ENS development can be tackled by in vitro studies. The myenteric plexus can be isolated and cultivated under the influence of the microenvironment (protein extracts). Although the postnatal myenteric plexus is not fully developed, the choice of embryological neuronal cells seems to be more effective for certain approaches. They can be isolated from the embryonic mouse gut and cultivated under the influence of various factors. This method seems to us a valuable tool for the investigation of the aetiology of motility disorders, although only a "complete" approach which considers all available methods will yield at the end a clear understanding which might lead to new therapeutical concepts.

Animals↗