Morphological phenotyping of enteric neurons using neurofilament immunohistochemistry renders chemical phenotyping more precise in porcine ileum

Brehmer, Axel; Schrödl, Falk; Neuhuber, Winfried

doi:10.1007/s00418-001-0373-z

Cited by 29 publications

(28 citation statements)

References 30 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The proportions in both myenteric plexus and ESP, estimated by CB/NF co-immunostaining, are quite comparable. In the myenteric plexus [Brehmer et al, 2002a], we found between 1.1 and 1.5% type V neurons in relation to the number of CB-stained neurons. In the ESP (this study), we estimated between 0.9 and 1.6% type V neurons in relation to all CB-stained neurons.…”

Section: Type V Neurons In the Esp: Proportion And Chemical Codingmentioning

confidence: 69%

Chemical Coding of Submucosal Type V Neurons in Porcine Ileum

Kapp

Schrödl²,

Neuhuber³

et al. 2006

Cells Tissues Organs

Self Cite

View full text Add to dashboard Cite

In this study, we attempted to determine the proportion of type V neurons relative to the putative whole neuron population in the two submucosal plexuses of pigs identified by their neurofilament immunoreactivity. The total neuron number was estimated in cuprolinic blue (CB)/anti-Hu protein (HU) costained wholemounts as the sum of the number of CB+/HU+, CB+/HU– and CB–/HU+ neurons. In the external submucosal plexus (ESP), HU labelled 98.6% and CB 97.3% of neurons. In the internal submucosal plexus, HU labelled 98.3%, whereas CB only marked 92.5% of neurons. Furthermore, we investigated the chemical coding of submucosal type V neurons and searched for submucosal, non-type V neurons displaying the same chemical coding as the myenteric type V neurons described earlier, i.e. the colocalization of calcitonin gene-related peptide (CGRP) and somatostatin (SOM). In order to facilitate immunohistochemical detection of neuroactive peptides, ileal segments were pretreated with colchicine prior to fixation. Type V neurons in the ESP occurred either as single cells displaying one or few prominent dendrite(s) or within aggregates displaying a dendritic tangle. In this plexus, type V neurons amounted to between 0.9 and 1.6% of all CB-stained neurons. ESP type V neurons displayed immunoreactivities for choline acetyl transferase (95.8%) and leucine-enkephalin (73.9%). All type V neurons were negative for neuronal nitric oxide synthase. Fifty-eight percent of ESP CGRP/SOM co-immunoreactive neurons displayed type V morphology, whereas 42% were non-type V neurons. Thus, the chemical coding of ESP type V neurons is in principal similar to that of the myenteric type V neurons described earlier. In the internal submucosal plexus, we found no type V neurons. In this plexus, 0.2% of all neurons counterstained with HU displayed CGRP/SOM coreactivity. As had been observed earlier concerning the myenteric type V neurons, ESP type V neurons were also closely apposed by conspicuous accumulations of boutons reactive for the same markers as the neurons themselves. Although we cannot exclude that axons of CGRP/SOM-reactive enteric, non-type V or extrinsic neurons end synaptically on type V neurons, we suggest that the main synaptic input to type V neurons originates from other type V neurons. This presents an argument for an interneuronal role of type V neurons.

show abstract

Section: Type V Neurons In the Esp: Proportion And Chemical Codingmentioning

confidence: 69%

Chemical Coding of Submucosal Type V Neurons in Porcine Ileum

Kapp

Schrödl²,

Neuhuber³

et al. 2006

Cells Tissues Organs

Self Cite

View full text Add to dashboard Cite

show abstract

“…It differs significantly from the proportion given for the guinea-pig, i.e., between 26% ) and 30% (Costa et al 1996). The difference is smaller between human and pig, in the latter species between 5 and 8% myenteric type II neurons were estimated (Brehmer et al 2002;Brehmer and Stach 1998). These discrepancies may, e.g., be related to differences in the neuronal composition between myenteric and submucosal ganglia in the various species Timmermans et al 2001).…”

Section: Discussionmentioning

confidence: 71%

Quantitative estimation of putative primary afferent neurons in the myenteric plexus of human small intestine

Weidmann

Schrödl

Neuhuber

et al. 2007

Histochem Cell Biol

Self Cite

View full text Add to dashboard Cite

This study aimed at estimating the proportion of human myenteric Dogiel type II neurons, putative intrinsic primary afferent neurons (IPANs), in relation to the entire myenteric neuron population. Since, at present, there is no known single marker, which specifically labels these neurons, we tried to identify the most appropriate marker combination based on the results of an earlier study. For this purpose, 10 wholemounts derived from human small intestinal segments were immunohistochemically triple-stained for calretinin (CALR), somatostatin (SOM) and neurofilaments (NF) and 9 were stained for substance P (SP), SOM and NF. In each wholemount, 15 ganglia selected randomly were evaluated. On the basis of their NF-reactivity, neurons reactive for one or co-reative for both of the other two markers, respectively, were morphologically classified as type II or non-type II neurons. We found that the majorities of neurons co-reactive for CALR/SOM and SP/SOM, respectively, were type II neurons whereas this was not the case for neurons, which were reactive for only one of the two markers. One of the statistical parameters estimated was the positive predictive value, the probability that a neuron displaying CALR/SOM- or SP/SOM-co-reactivity, respectively, is a type II neuron. This value was 97% in case of CALR/SOM- and 95% in case of SP/SOM-co-staining. Although the difference of the statistical parameters between the two stainings was not significant, CALR and SOM were used to estimate indirectly the proportion of type II neurons, in wholemounts co-stained with the pan-neuronal marker neuronal protein HuC/HuD (HU). In these wholemounts, altogether 9.1% of neurons were coreactive for CALR/SOM. We suggest that the proportion of myenteric type II neurons in the human small intestine is related to the proportion of CALR/SOM-co-reactive neurons and may be near to one tenth of the total myenteric neuronal population.

show abstract

“…(Stach, 1989;Brehmer et al, 2002aBrehmer et al, , 2002b. The fact that among 50 randomly selected CGRP-reactive neurons, many more were type II neurons in comparison to type V, reflects their quite different proportions in ileal myenteric ganglia: between 7 and 8% of the total population were found to be type II neurons, whereas less than 1.5% were type V neurons (Brehmer et al, 2002b). While type II neurons were generally not surrounded by CGRP-positive boutons, the somata and dendritic processes of type V neurons were regularly outlined by CGRP-positive boutons.…”

Section: Discussionmentioning

confidence: 99%

“…However, several studies revealed that this peptide, in colocalization with a marker for cholinergic neurons (choline acetyl transferase, ChAT), is present also in neurofilament (NF) reactive, non-type II neurons, indicating that the chemical code NF/CGRP/ChAT, with NF as structural marker, is not specific for type II neurons (Brehmer et al, 2002a,b;Jungbauer et al, 2006). The inclusion of NF into the definition of the chemical code is appropriate because this cytoskeletal protein is present only in subpopulations of enteric neurons (Costa et al, 1996;Brookes, 2001;Brehmer et al, 2002b;Ganns et al, 2006). This study deals only with neurons in the myenteric plexus, because only in this network has the morphology, including the projection pattern of type II neurons and other neuronal populations, been sufficiently investigated.…”

mentioning

confidence: 99%

Calcitonin Gene‐Related Peptide: A Marker for Putative Primary Afferent Neurons in the Pig Small Intestinal Myenteric Plexus?

Wolf

Schrödl

Neuhuber

et al. 2007

The Anatomical Record

Self Cite

View full text Add to dashboard Cite

For years, calcitonin gene-related peptide (CGRP) has been used as a marker peptide for Dogiel type II neurons, putative intrinsic primary afferent neurons, in the pig enteric nervous system. Recently, some studies showed CGRP-positive neurons displaying distinctly different shapes. The aims of this study were to evaluate (1) the proportion of myenteric type II neurons that contain CGRP and (2) the proportion of myenteric CGRP-positive neurons that display type II vs. non-type II morphologies and to conclude if this peptide could be suited as a marker for type II neurons. For this purpose, nine myenteric whole-mounts (each one from duodenum, jejunum, and ileum, respectively, derived from three pigs) were triple-immunostained for CGRP, neurofilaments (NF), and choline acetyl transferase (ChAT). Each whole-mount was evaluated twice. First, 50 NF-stained type II neurons were selected randomly and their coreactivities for CGRP and ChAT were observed. Second, 50 CGRP-positive neurons were located randomly and their NF morphology and ChAT coreactivity were observed. Altogether, 92% of all type II neurons investigated displayed CGRP immunoreactivity, whereas 94.9% of all CGRP-reactive neurons recorded displayed type II morphology. We observed three further shapes of CGRP-positive neurons: 7 type V neurons (all were ChAT-positive; mainly in the ileal whole-mounts), 6 type I-like neurons (all were ChAT-positive), and 14 type III-like neurons (mostly ChAT-negative; mainly in duodenal and jejunal specimens). We conclude that CGRP-antibodies can be used as markers for type II neurons in the pig small intestinal myenteric plexus in quantitative studies but it should be kept in mind that up to one-tenth of CGRP-reactive neurons may be nontype II neurons. In case of single cell evaluation, CGRP-immunoreactivity alone is not suited as a marker. In such cases additional, morphological analysis is necessary.

show abstract

Morphological phenotyping of enteric neurons using neurofilament immunohistochemistry renders chemical phenotyping more precise in porcine ileum

Cited by 29 publications

References 30 publications

Chemical Coding of Submucosal Type V Neurons in Porcine Ileum

Chemical Coding of Submucosal Type V Neurons in Porcine Ileum

Quantitative estimation of putative primary afferent neurons in the myenteric plexus of human small intestine

Calcitonin Gene‐Related Peptide: A Marker for Putative Primary Afferent Neurons in the Pig Small Intestinal Myenteric Plexus?

Contact Info

Product

Resources

About