Methods to Study the Myenteric Plexus of Rat Small Intestine

AbstractThe close interaction between the enteric nervous system, microbiome, and brain in vertebrates is an emerging topic of recent studies. Different species such as rat, mouse, and human are currently being used for this purpose, among others. The transferability of protocols for tissue isolation and sample collection is not always straightforward. Thus, the present work presents a new protocol for isolation and sample collection of rat myenteric plexus cells for in vivo as well as in vitro studies. With the methods and chemicals described in detail, a wide variety of investigations can be performed with regard to normal physiological as well as pathological processes in the postnatal developing enteric nervous system. The fast and efficient preparation of the intestine as the first step is particularly important. We have developed and described a LIENS chamber to obtain optimal tissue quality during intestinal freezing. Cryosections of the flat, snap-frozen intestine can then be prepared for histological examination of the various wall layers of the intestine, e.g. by immunohistochemistry. In addition, these cryosections are suitable for the preparation of defined regions, as shown here using the ganglia of the mesenteric plexus. This specific tissue was obtained by laser microdissection, making the presented methodology also suitable for subsequent analyses that require high quality (specificity) of the samples. Furthermore, we present here a fully modernized protocol for the cultivation of myenteric neurons from the rat intestine, which is suitable for a variety of in vitro studies.

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KBP interacts with SCG10, linking Goldberg–Shprintzen syndrome to microtubule dynamics and neuronal differentiation

Human Molecular Genetics ◽

10.1093/hmg/ddq280 ◽

2010 ◽

Vol 19 (18) ◽

pp. 3642-3651 ◽

Cited By ~ 30

Author(s):

Maria M. Alves ◽

Grzegorz Burzynski ◽

Jean-Marie Delalande ◽

Jan Osinga ◽

Annemieke van der Goot ◽

...

Keyword(s):

Nervous System ◽

Enteric Nervous System ◽

Neuronal Differentiation ◽

Cortical Neurons ◽

Neuronal Development ◽

Direct Interaction ◽

Clinical Disorder ◽

Neurite Development

Abstract Goldberg–Shprintzen syndrome (GOSHS) is a rare clinical disorder characterized by central and enteric nervous system defects. This syndrome is caused by inactivating mutations in the Kinesin Binding Protein (KBP) gene, which encodes a protein of which the precise function is largely unclear. We show that KBP expression is up-regulated during neuronal development in mouse cortical neurons. Moreover, KBP-depleted PC12 cells were defective in nerve growth factor-induced differentiation and neurite outgrowth, suggesting that KBP is required for cell differentiation and neurite development. To identify KBP interacting proteins, we performed a yeast two-hybrid screen and found that KBP binds almost exclusively to microtubule associated or related proteins, specifically SCG10 and several kinesins. We confirmed these results by validating KBP interaction with one of these proteins: SCG10, a microtubule destabilizing protein. Zebrafish studies further demonstrated an epistatic interaction between KBP and SCG10 in vivo . To investigate the possibility of direct interaction between KBP and microtubules, we undertook co-localization and in vitro binding assays, but found no evidence of direct binding. Thus, our data indicate that KBP is involved in neuronal differentiation and that the central and enteric nervous system defects seen in GOSHS are likely caused by microtubule-related defects.

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Cannabinoid CB2 receptors in the enteric nervous system modulate gastrointestinal contractility in lipopolysaccharide-treated rats

AJP Gastrointestinal and Liver Physiology ◽

10.1152/ajpgi.90285.2008 ◽

2008 ◽

Vol 295 (1) ◽

pp. G78-G87 ◽

Cited By ~ 81

Author(s):

Marnie Duncan ◽

Abdeslam Mouihate ◽

Ken Mackie ◽

Catherine M. Keenan ◽

Nancy E. Buckley ◽

...

Keyword(s):

Nervous System ◽

Enteric Nervous System ◽

Myenteric Plexus ◽

Electrical Field Stimulation ◽

Receptor Expression ◽

Dependent Manner ◽

Concentration Dependent Manner ◽

Receptor Agonists ◽

Lps Treatment

Enhanced intestinal transit due to lipopolysaccharide (LPS) is reversed by cannabinoid (CB)2 receptor agonists in vivo, but the site and mechanism of action are unknown. We have tested the hypothesis that CB2 receptors are expressed in the enteric nervous system and are activated in pathophysiological conditions. Tissues from either saline- or LPS-treated (2 h; 65 μg/kg ip) rats were processed for RT-PCR, Western blotting, and immunohistochemistry or were mounted in organ baths where electrical field stimulation was applied in the presence or absence of CB receptor agonists. Whereas the CB2 receptor agonist JWH133 did not affect the electrically evoked twitch response of the ileum under basal conditions, in the LPS-treated tissues JWH133 was able to reduce the enhanced contractile response in a concentration-dependent manner. Rat ileum expressed CB2 receptor mRNA and protein under physiological conditions, and this expression was not affected by LPS treatment. In the myenteric plexus, CB2 receptors were expressed on the majority of neurons, although not on those expressing nitric oxide synthase. LPS did not alter the distribution of CB2 receptor expression in the myenteric plexus. In vivo LPS treatment significantly increased Fos expression in both enteric glia and neurons. This enhanced expression was significantly attenuated by JWH133, whose action was reversed by the CB2 receptor antagonist AM630. Taking these facts together, we conclude that activation of CB2 receptors in the enteric nervous system of the gastrointestinal tract dampens endotoxin-induced enhanced intestinal contractility.

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Lymphocyte-mediated regulation of β-endorphin in the myenteric plexus

AJP Gastrointestinal and Liver Physiology ◽

10.1152/ajpgi.00318.2006 ◽

2007 ◽

Vol 292 (1) ◽

pp. G344-G348 ◽

Cited By ~ 16

Author(s):

Monica Verma-Gandhu ◽

Elena F. Verdu ◽

Daniel Cohen-Lyons ◽

Stephen M. Collins

Keyword(s):

T Cells ◽

Nervous System ◽

T Cell ◽

Enteric Nervous System ◽

Myenteric Plexus ◽

Pain Perception ◽

Visceral Pain ◽

Receptor Expression ◽

Visceral Hyperalgesia

Lymphocytes are antinociceptive and can modulate visceral pain perception in mice. Previously, we have shown that adoptive transfer of CD4+ T cells to severe combined immune-deficient (SCID) mice normalized immunodeficiency-related visceral hyperalgesia. Pain attenuation was associated with an increase in β-endorphin release by T cells and an upregulation of β-endorphin in the enteric nervous system. In this study, we investigated the relationship between T cells and opioid expression in the myenteric plexus. We examined opioid peptide and receptor expression in the myenteric plexus in the presence and absence of mucosal T cells. We found a positive association between T cells and β-endorphin expression; this was accompanied by a downregulation of the μ-opioid receptor (MOR). In vitro, T helper (Th) type 1 and type 2 cytokine stimulation of CD4+ T cells or isolation of T cells from in vivo Th-polarized mice did not increase T cell release of β-endorphin or the induction of β-endorphin expression in the myenteric plexus. However, exogenous β-endorphin did upregulate β-endorphin expression, and both cycloheximide and naloxone methiodide inhibited peptide upregulation. Therefore, our results suggest that nonpolarized CD4+ T cells release β-endorphin, which, through an interaction with MOR, stimulates an upregulation of β-endorphin expression in the myenteric plexus. Thus, we propose that the mechanism underlying lymphocyte modulation of visceral pain involves T cell modulation of opioid expression in the enteric nervous system.

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Migration and differentiation of neural crest cells and their derivatives : in vivo and in vitro studies on the early development of the avian peripheral nervous system

Reproduction Nutrition Development ◽

10.1051/rnd:19820201 ◽

1982 ◽

Vol 22 (1B) ◽

pp. 153-162 ◽

Cited By ~ 4

Author(s):

Catherine ZILLER ◽

J. SMITH

Keyword(s):

Nervous System ◽

Neural Crest ◽

Peripheral Nervous System ◽

Early Development ◽

Neural Crest Cells ◽

In Vitro Studies

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Multipotential progenitors of the mammalian enteric nervous system capable of colonising aganglionic bowel in organ culture

Development ◽

10.1242/dev.126.1.157 ◽

1999 ◽

Vol 126 (1) ◽

pp. 157-168 ◽

Cited By ~ 4

Author(s):

D. Natarajan ◽

M. Grigoriou ◽

C.V. Marcos-Gutierrez ◽

C. Atkins ◽

V. Pachnis

Keyword(s):

Nervous System ◽

Organ Culture ◽

Enteric Nervous System ◽

Culture System ◽

Culture Conditions ◽

Wild Type ◽

Enteric Ganglia ◽

Mammalian Embryos

The enteric nervous system of vertebrates is derived from neural crest cells that invade the gut wall and generate a highly organised network of enteric ganglia. Among the genes that play an important role in ENS development is c-Ret, mutations of which result in failure of formation of enteric ganglia (intestinal aganglionosis). To further understand the development of the mammalian ENS in general and the mechanism of action of the RET RTK in particular, we have developed and used an organotypic culture system of mouse fetal gut. At the stage of culture initiation, the gut is partially populated by undifferentiated ENS progenitors, but culture for several days results in extensive neuronal and glial differentiation. Using this organ culture system, we have compared the development of the ENS in wild-type and RET-deficient gut and showed that the aganglionic phenotype observed in vivo is consistently reproduced under the in vitro culture conditions. Microinjection of RET+ cells isolated from E11.5 mouse bowel into wild-type or RET-deficient aganglionic gut in organ culture, results in extensive repopulation of their wall by exogenously derived neurons and glia. Finally, using a similar approach, we demonstrate that single RET+ cells introduced into the wall of wild-type gut generate both cell lineages of the ENS, i.e. neurons and glia. Our data show the NC-derived RET+ population of fetal gut in mammalian embryos consists of multipotential progenitors capable of colonising efficiently both wild-type and RET-deficient aganglionic bowel in organ culture.

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Squalamine Restores the Function of the Enteric Nervous System in Mouse Models of Parkinson’s Disease

Journal of Parkinson s Disease ◽

10.3233/jpd-202076 ◽

2020 ◽

Vol 10 (4) ◽

pp. 1477-1491

Author(s):

Christine L. West ◽

Yu-Kang Mao ◽

Thilini Delungahawatta ◽

Jessica Y. Amin ◽

Sohana Farhin ◽

...

Keyword(s):

Parkinson’S Disease ◽

Parkinson's Disease ◽

Nervous System ◽

Enteric Nervous System ◽

Mouse Models ◽

Colonic Motility ◽

Autonomic Nerves ◽

Nerve Recordings

Background: Parkinson’s disease (PD) is a progressive neurodegenerative disorder thought to be caused by accumulation of α-synuclein (α-syn) within the brain, autonomic nerves, and the enteric nervous system (ENS). Involvement of the ENS in PD often precedes the onset of the classic motor signs of PD by many years at a time when severe constipation represents a major morbidity. Studies conducted in vitro and in vivo, have shown that squalamine, a zwitterionic amphipathic aminosterol, originally isolated from the liver of the dogfish shark, effectively displaces membrane-bound α-syn. Objective: Here we explore the electrophysiological effect of squalamine on the gastrointestinal (GI) tract of mouse models of PD engineered to express the highly aggregating A53T human α-syn mutant. Methods: GI motility and in vivo response to oral squalamine in PD model mice and controls were assessed using an in vitro tissue motility protocol and via fecal pellet output. Vagal afferent response to squalamine was measured using extracellular mesenteric nerve recordings from the jejunum. Whole cell patch clamp was performed to measure response to squalamine in the myenteric plexus. Results: Squalamine effectively restores disordered colonic motility in vivo and within minutes of local application to the bowel. We show that topical squalamine exposure to intrinsic primary afferent neurons (IPANs) of the ENS rapidly restores excitability. Conclusion: These observations may help to explain how squalamine may promote gut propulsive activity through local effects on IPANs in the ENS, and further support its possible utility in the treatment of constipation in patients with PD.

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Infeccions as the etiology for obesity

Arquivos Brasileiros de Endocrinologia & Metabologia ◽

10.1590/s0004-27302009000200007 ◽

2009 ◽

Vol 53 (2) ◽

pp. 159-164 ◽

Cited By ~ 3

Author(s):

Henrique de Lacerda Suplicy ◽

Andressa Bornschein

Keyword(s):

Central Nervous System ◽

Nervous System ◽

In Vitro Studies ◽

In Vivo Studies ◽

Adenovirus Infection ◽

Fatty Tissue ◽

Obese Subjects

The role of infection on obesity development has been questioned since the early 1980's. Several studies on animals have shown that fisiopathologic mechanisms through which infections can produce obesity do exist. At least eight types of obesity-inducing viruses have been identified in animals, especially poultry and mice. Studies on humans are far less convincing; however, two adenoviruses, Ad-36 and SMAM-1, have shown adipogenic properties. In vitro studies with 3T3-L1 cells stated the activation of the enzymatic pathway that leads to fatty tissue accumulation; in vivo studies have also detected higher levels of antibodies against such viruses on obese subjects. Although most known infections nowadays cause obesity through central nervous system lesions, the Ad-36 adenovirus infection affects fatty tissue directly, raising doubts regarding central role component in this case.

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