Marion Raab - Academia.edu (original) (raw)

Papers by Marion Raab

Research paper thumbnail of Innervation of the Mammalian Esophagus

Advances in Anatomy, Embryology and Cell Biology, 2006

The use of general descriptive names, registered names, trademarks, etc. in this publication does... more The use of general descriptive names, registered names, trademarks, etc. in this publication does not imply, even in the absence of a specific statement, that such names are exempt from the relevant protective laws and regulations and therefore free for general use. Product liability: The publisher cannot guarantee the accuracy of any information about dosage and application contained in this book. In every individual case the user must check such information by consulting the relevant literature.

Research paper thumbnail of Neurotrophin-4 dependency of intraepithelial vagal sensory nerve terminals that selectively contact pulmonary NEBs in mice expressing populations of vagal myelinated afferents, only one is distinctly reduced in NT-4 deficient mice, suggesting the involvement of NTs. In view of the growing evidenc...

Research paper thumbnail of “Gedeckt perforiertes Aneurysma der Arteria lienalis während der Schwangerschaft“

Research paper thumbnail of “Putative vagal mechanosensors in the esophagus of the mouse depend on NT-3”

Research paper thumbnail of Exaktes intraoperatives Lymphknotenstaging beim Ösophaguskarzinom im Rahmen des multimodalen Therapiekonzeptes /

Research paper thumbnail of Glutamatergic intraganglionic laminar endings (IGLEs) and their relationships with the neuropil of myenteric ganglia in the esophagus of rat and mouse

Research paper thumbnail of ”Quality control by systematic nodal staging in surgical treatment of esophageal carcinoma”

Research paper thumbnail of Glutamate receptors 2 & 3 (GluR 2/3) on myenteric neurons in the mouse esophagus –targets of glutamate released from IGLEs?

Intraganglionic laminar endings (IGLEs) are the most frequent vagal afferent endings in the gut a... more Intraganglionic laminar endings (IGLEs) are the most frequent vagal afferent endings in the gut and contain the vesicular glutamate transporter 2 (VGLUT2) in both rat and mouse esoph-agus (Raab & Neuhuber, 2003; Raab & Neuhuber, 2004). They represent one important though not the only source of glutamate in myenteric ganglia since enteric neurons as well as glia also contain glutamate, VGLUT1 and glutamine synthase (Kato et al., 1990; Liu et al. 1997; Kraus et al. 2007). In this study we analyzed the distribution of ionotropic non-NMDA receptors GluR2/3, one possible target for ganglionic glutamate. Immunohistochemistry in esophageal wholemounts showed GluR2/3-immunoreactivity (-ir) in nearly 30% of myenteric neurons. To determine the neuronal subpopulations which express GluR2/3 receptors, we per-formed NADPh-diaphorase histochemistry and combined GluR2/3 with nNOS- and ChAT- immunohistochemistry, respectively. Seventy-three % of myenteric neurons were nitrergic, 22% cholinergic and...

Research paper thumbnail of Neurotrophin-4 dependency of intraepithelial vagal sensory nerve terminals that selectively contact pulmonary NEBs in mice

Histology and histopathology, Aug 1, 2010

Important physiological functions of neurotrophins (NTs) in airways and lungs are the early devel... more Important physiological functions of neurotrophins (NTs) in airways and lungs are the early development, differentiation and maintenance of peripheral sensory neurons. The main pulmonary sensory innervation is of vagal origin, with several nerve fibre populations that selectively contact complex morphologically well-characterized receptor end-organs, called neuroepithelial bodies (NEBs). NEBs in mouse lungs are innervated by at least two separate myelinated vagal sensory nerve fibre populations, of which the neurochemical coding is suggestive of a mechanosensory function. Since neurotrophin-4 (NT-4) has been especially described to be important for the maintenance of mechanosensory nerve terminals, the present study aimed at investigating the NT-4 dependency of the two myelinated vagal sensory nerve fibre populations innervating mouse pulmonary NEBs. Multiple immunostaining in 21-day-old and adult mouse lungs revealed the expression of the NT-4 receptor TrkB on the two different mye...

Research paper thumbnail of Vesicular glutamate transporter 1 immunoreactivity in motor endplates of striated esophageal but not skeletal muscles in the mouse

Neuroscience Letters, 2004

Glutamate, the major excitatory transmitter in the central nervous system, has been speculated fo... more Glutamate, the major excitatory transmitter in the central nervous system, has been speculated for years to influence mammalian motor endplates but trials to identify glutamatergic motor terminals failed because specific markers were not available. Recently, antibodies to vesicular glutamate transporters (VGLUTs) opened new possibilities for further morphological investigations. We detected VGLUT1 immunoreactivity (-ir), but not VGLUT2-ir and VGLUT3-ir, respectively, in many motor nerve terminals in motor endplates of the mouse esophagus as identified by alpha-bungarotoxin or colocalization of VGLUT1 with choline acetyltransferase. These findings suggest that glutamate is co-stored with acetylcholine in esophageal neuromuscular junctions. Surprisingly, we found neither VGLUT1-ir nor VGLUT2-ir or VGLUT3-ir in neuromuscular junctions of somitic and branchiogenic skeletal muscles. This may reflect differences in functional properties and the embryonic origin between skeletal and esophageal striated muscle fibers.

Research paper thumbnail of Proline-rich synapse-associated protein-1 and 2 (ProSAP1/Shank2 and ProSAP2/Shank3)—scaffolding proteins are also present in postsynaptic specializations of the peripheral nervous system

Neuroscience, 2010

Proline-rich synapse-associated protein-1 and 2 (ProSAP1/Shank2 and ProSAP2/Shank3) were original... more Proline-rich synapse-associated protein-1 and 2 (ProSAP1/Shank2 and ProSAP2/Shank3) were originally found as synapse-associated protein 90/postsynaptic density protein-95-associated protein (SAPAP)/guanylate-kinase-associated protein (GKAP) interaction partners and also isolated from synaptic junctional protein preparations of rat brain. They are essential components of the postsynaptic density (PSD) and are specifically targeted to excitatory asymmetric type 1 synapses. Functionally, the members of the ProSAP/Shank family are one of the postsynaptic key elements since they link and attach the postsynaptic signaling apparatus, for example N-methyl-d-aspartic acid (NMDA)-receptors via direct and indirect protein interactions to the actin-based cytoskeleton. The functional significance of ProSAP1/2 for synaptic transmission and the paucity of data with respect to the molecular composition of PSDs of the peripheral nervous system (PNS) stimulated us to investigate neuromuscular junctions (NMJs), synapses of the superior cervical ganglion (SCG), and synapses in myenteric ganglia as representative synaptic junctions of the PNS. Confocal imaging revealed ProSAP1/2-immunoreactivity (-iry) in NMJs of rat and mouse sternomastoid and tibialis anterior muscles. In contrast, ProSAP1/2-iry was only negligibly found in motor endplates of striated esophageal muscle probably caused by antigen masking or a different postsynaptic molecular anatomy at these synapses. ProSAP1/2-iry was furthermore detected in cell bodies and dendrites of superior cervical ganglion neurons and myenteric neurons in esophagus and stomach. Ultrastructural analysis of ProSAP1/2 expression in myenteric ganglia demonstrated that ProSAP1 and ProSAP2 antibodies specifically labelled PSDs of myenteric neurons. Thus, scaffolding proteins ProSAP1/2 were found within the postsynaptic specializations of synapses within the PNS, indicating a similar molecular assembly of central and peripheral postsynapses.

Research paper thumbnail of Pitfalls using tyramide signal amplification (TSA) in the mouse gastrointestinal tract: Endogenous streptavidin-binding sites lead to false positive staining

Journal of Neuroscience Methods, 2012

Highly sensitive immunohistochemical detection systems such as tyramide signal amplification (TSA... more Highly sensitive immunohistochemical detection systems such as tyramide signal amplification (TSA) are widely used, since they allow using two primary antibodies raised in the same species. Most of them are based on the streptavidin-biotin-peroxidase system and include streptavidin-coupled secondary antibodies. Using TSA in cryostat-sectioned tissues of mouse esophagus, we were puzzled by negative controls with unexpected staining mostly in the ganglionic areas. This prompted us to search for the causing agent and to include also other parts of the mouse gastrointestinal tract for comparison. Streptavidin-coupled antibodies bound to endogenous binding sites yet to be characterized, which are present throughout the mouse intestines. Staining was mainly localized around neuronal cell bodies of enteric ganglia. Thus, caution is warranted when applying streptavidin-coupled antibodies in the mouse gastrointestinal tract. The use of endogenous biotin-blocking kits combined with a prolonged post-fixation time could significantly reduce unintentional staining.

Research paper thumbnail of Number and Distribution of Intraganglionic Laminar Endings in the Mouse Esophagus as Demonstrated with Two Different Immunohistochemical Markers

Journal of Histochemistry & Cytochemistry, 2005

Intraganglionic laminar endings (IGLEs) represent the only vagal mechanosensory terminals in the ... more Intraganglionic laminar endings (IGLEs) represent the only vagal mechanosensory terminals in the tunica muscularis of the esophagus. Two specific markers for IGLEs were recently described in mouse: the purinergic P2X2 receptor and the vesicular glutamate transporter 2 (VGLUT2). This study aimed at comparing both markers with respect to their suitability for quantitative analysis. We counted IGLEs immunostained for VGLUT2 and P2X2, respectively, and mapped their distribution in esophageal wholemounts of C57Bl/6 mice. Numbers and distribution of IGLEs were compared with those of myenteric ganglia as demonstrated by cuprolinic blue histochemistry. Whereas the distribution of VGLUT2-immunopositive IGLEs closely matched that of myenteric ganglia, P2X2-immunopositive IGLEs were rarely found in upper and middle esophagus but increasingly in its lower parts. P2X2 stained only half the number of IGLEs found with VGLUT2 immunostaining. We also investigated the correlation between anterograde ...

Research paper thumbnail of Localization of receptors for calcitonin-gene-related peptide to intraganglionic laminar endings of the mouse esophagus: peripheral interaction between vagal and spinal afferents?

Histochemistry and Cell Biology, 2013

The calcitonin gene-related peptide (CGRP)-receptor is a heterodimer of calcitonin receptorlike r... more The calcitonin gene-related peptide (CGRP)-receptor is a heterodimer of calcitonin receptorlike receptor (CLR) and receptor activity modifying protein 1 (RAMP1). Despite the importance of CGRP in regulating gastrointestinal functions, nothing is known about the distribution and function of CLR/RAMP1 in the esophagus, where up to 90% of spinal afferent neurons contain CGRP. We detected CLR/RAMP1 in the mouse esophagus using immunofluorescence and confocal laser scanning microscopy and examined their relationship with neuronal elements of the myenteric plexus. Immunoreactivity for CLR and RAMP1 colocalized with VGLUT2-positive IGLEs, which were contacted by CGRP-positive varicose axons presumably of spinal afferent origin, typically at sites of CRL/ RAMP1 immunoreactivity. This provides an anatomical basis for interaction between spinal afferent fibres and IGLEs. Immunoreactive CLR and RAMP1 also colocalized in myenteric neurons. Thus, CGRP-containing spinal afferents may interact with both vagal IGLEs and myenteric neurons in the mouse esophagus, possibly modulating motility reflexes and inflammatory hypersensitivity.

Research paper thumbnail of Quantitative evaluation of neurons in the mucosal plexus of adult human intestines

Histochemistry and Cell Biology, 2011

Research paper thumbnail of Distribution of P2X3 receptor immunoreactivity in myenteric ganglia of the mouse esophagus

Histochemistry and Cell Biology, 2008

Intraganglionic laminar endings (IGLEs) represent the major vagal afferent terminals throughout t... more Intraganglionic laminar endings (IGLEs) represent the major vagal afferent terminals throughout the gut. Electrophysiological experiments revealed a modulatory role of ATP in the IGLE-mechanotransduction process and the P2X(2)-receptor has been described in IGLEs of mouse, rat and guinea pig. Another purinoceptor, the P2X(3)-receptor, was found in IGLEs of the rat esophagus. These findings prompted us to investigate occurrence and distribution of the P2X(3)-receptor in the mouse esophagus. Using multichannel immunofluorescence and confocal microscopy, P2X(3)-immunoreactivity (-iry) was found colocalized with the vesicular glutamate transporter 2 (VGLUT2), a specific marker for IGLEs, on average in three-fourths of esophageal IGLEs. The distribution of P2X(3) immunoreactive (-ir) IGLEs was similar to that of P2X(2)-iry and showed increasing numbers towards the abdominal esophagus. P2X(3)/P2X(2)-colocalization within IGLEs suggested the occurrence of heteromeric P2X(2/3) receptors. In contrast to the rat, where only a few P2X(3)-ir perikarya were described, P2X(3) stained perikarya in ~80% of myenteric ganglia in the mouse. Detailed analysis revealed P2X(3)-iry in subpopulations of nitrergic (nNOS) and cholinergic (ChAT) myenteric neurons and ganglionic neuropil of the mouse esophagus. We conclude that ATP might act as a neuromodulator in IGLEs via a (P2X(2))-P2X(3) receptor-mediated pathway especially in the abdominal portion of the mouse esophagus.

Research paper thumbnail of Vesicular glutamate transporter 1 immunoreactivity in extrinsic and intrinsic innervation of the rat esophagus

Histochemistry and Cell Biology, 2005

Encouraged by the recent finding of vesicular glutamate transporter 2 (VGLUT2) immunoreactivity (... more Encouraged by the recent finding of vesicular glutamate transporter 2 (VGLUT2) immunoreactivity (-ir) in intraganglionic laminar endings (IGLEs) of the rat esophagus, we investigated also the distribution and co-localization patterns of VGLUT1. Confocal imaging revealed substantial co-localization of VGLUT1-ir with selective markers of IGLEs, i.e., calretinin and VGLUT2, indicating that IGLEs contain both VGLUT1 and VGLUT2 within their synaptic vesicles. Besides IGLEs, we found VGLUT1-ir in both cholinergic and nitrergic myenteric neuronal cell bodies, in fibers of the muscularis mucosae, and in esophageal motor endplates. Skeletal neuromuscular junctions, in contrast, showed no VGLUT1-ir. We also tested for probable co-localization of VGLUT1-ir with markers of extrinsic and intrinsic esophageal innervation and glia. Within the myenteric neuropil we found, besides co-localization of VGLUT1 and substance P, no further co-localization of VGLUT1-ir with any of these markers. In the muscularis mucosae some VGLUT1-ir fibers were shown to contain neuronal nitric oxide synthase (nNOS)-ir. VGLUT1-ir in esophageal motor endplates was partly co-localized with vesicular acetylcholine transporter (VAChT)/choline acetyltransferase (ChAT)-ir, but VGLUT1-ir was also demonstrated in separately terminating fibers at motor endplates co-localized neither with ChAT/VAChT-ir nor with nNOS-ir, suggesting a hitherto unknown glutamatergic enteric co-innervation. Thus, VGLUT1-ir was found in extrinsic as well as intrinsic innervation of the rat esophagus.

Research paper thumbnail of Intraganglionic laminar endings and their relationships with neuronal and glial structures of myenteric ganglia in the esophagus of rat and mouse

Histochemistry and Cell Biology, 2000

Intraganglionic laminar endings (IGLEs) represent the only vagal mechanosensory terminals in the ... more Intraganglionic laminar endings (IGLEs) represent the only vagal mechanosensory terminals in the tunica muscularis of the esophagus and may be involved in local reflex control. We recently detected extensive though not complete colocalization of the vesicular glutamate transporter 2 (VGLUT2) with markers for IGLEs. To elucidate this colocalization mismatch, this study aimed at identifying markers for nitrergic, cholinergic, peptidergic, and adrenergic neurons and glial cells, which may colocalize with VGLUT2 outside of IGLEs. Confocal imaging revealed, besides substantial colocalization of VGLUT2 and substance P (SP), no other significant colocalizations of VGLUT2 and immunoreactivity for any of these markers within the same varicosities. However, we found close contacts of VGLUT2-positive structures to vesicular acetylcholine transporter, choline acetyltransferase, neuronal nitric oxide synthase, galanin, neuropeptide Y, and vasoactive intestinal peptide immunoreactive cell bodies and varicosities, as well as to glial cells. Neuronal perikarya were never positive for VGLUT2. Thus, VGLUT2 was almost exclusively found in IGLEs and may serve as a specific marker for them. In addition, many IGLEs also contained SP. The close contacts established by IGLEs to myenteric cell bodies, dendrites, and varicose fibers suggest that IGLEs modulate various types of enteric neurons and vice versa.

Research paper thumbnail of Surgery of a splenic artery aneurysm during pregnancy

European Journal of Obstetrics & Gynecology and Reproductive Biology, 2002

We report a case of ligation of the splenic artery with splenectomy during pregnancy due to a spl... more We report a case of ligation of the splenic artery with splenectomy during pregnancy due to a splenic artery aneurysm. The risk of aneurysmal rupture is increased in multipara and during pregnancy. As a result of high maternal and fetal morbidity and mortality elective surgery should be performed.

Research paper thumbnail of Muscarinic acetylcholine receptors in the mouse esophagus: focus on vagal intraganglionic laminar endings (IGLEs)

Autonomic Neuroscience, 2013

ABSTRACT IGLEs represent the only low-threshold vagal mechanosensory terminals in the tunica musc... more ABSTRACT IGLEs represent the only low-threshold vagal mechanosensory terminals in the tunica muscularis of the esophagus. Previously, close relationships of vesicular glutamate transporter 2 (VGLUT2) immunopositive IGLEs and cholinergic varicosities suggestive for direct contacts were described in almost all mouse esophageal myenteric ganglia. Possible cholinergic influence on IGLEs requires specific acetylcholine receptors. In particular, the occurrence and location of neuronal muscarinic acetylcholine receptors (mAChR) in the esophagus were not yet characterized. This study aimed at specifying relationships of VGLUT2 immunopositive IGLEs and vesicular acetylcholine transporter (VAChT)-immunopositive varicosities using preembedding electron microscopy and the location of mAChR1-3 (M1-3) within esophagus and nodose ganglia using multilabel immunofluorescence and retrograde tracing. Electron microscopy confirmed synaptic contacts between cholinergic varicosities and IGLEs. M1- and M2-immunoreactivity (-iry) was colocalized with VGLUT2-iry in subpopulations of IGLEs. Retrograde Fast Blue tracing from the esophagus showed nodose ganglion neurons colocalizing tracer and M2-iry. Acetylcholine probably released from varicosities of both extrinsic and intrinsic origin may influence a subpopulation of esophageal IGLEs via M2 and M1 receptors. (Supported by Johannes und Frieda Marohn-Stiftung, Erlangen).

Research paper thumbnail of Innervation of the Mammalian Esophagus

Advances in Anatomy, Embryology and Cell Biology, 2006

The use of general descriptive names, registered names, trademarks, etc. in this publication does... more The use of general descriptive names, registered names, trademarks, etc. in this publication does not imply, even in the absence of a specific statement, that such names are exempt from the relevant protective laws and regulations and therefore free for general use. Product liability: The publisher cannot guarantee the accuracy of any information about dosage and application contained in this book. In every individual case the user must check such information by consulting the relevant literature.

Research paper thumbnail of Neurotrophin-4 dependency of intraepithelial vagal sensory nerve terminals that selectively contact pulmonary NEBs in mice expressing populations of vagal myelinated afferents, only one is distinctly reduced in NT-4 deficient mice, suggesting the involvement of NTs. In view of the growing evidenc...

Research paper thumbnail of “Gedeckt perforiertes Aneurysma der Arteria lienalis während der Schwangerschaft“

Research paper thumbnail of “Putative vagal mechanosensors in the esophagus of the mouse depend on NT-3”

Research paper thumbnail of Exaktes intraoperatives Lymphknotenstaging beim Ösophaguskarzinom im Rahmen des multimodalen Therapiekonzeptes /

Research paper thumbnail of Glutamatergic intraganglionic laminar endings (IGLEs) and their relationships with the neuropil of myenteric ganglia in the esophagus of rat and mouse

Research paper thumbnail of ”Quality control by systematic nodal staging in surgical treatment of esophageal carcinoma”

Research paper thumbnail of Glutamate receptors 2 & 3 (GluR 2/3) on myenteric neurons in the mouse esophagus –targets of glutamate released from IGLEs?

Intraganglionic laminar endings (IGLEs) are the most frequent vagal afferent endings in the gut a... more Intraganglionic laminar endings (IGLEs) are the most frequent vagal afferent endings in the gut and contain the vesicular glutamate transporter 2 (VGLUT2) in both rat and mouse esoph-agus (Raab & Neuhuber, 2003; Raab & Neuhuber, 2004). They represent one important though not the only source of glutamate in myenteric ganglia since enteric neurons as well as glia also contain glutamate, VGLUT1 and glutamine synthase (Kato et al., 1990; Liu et al. 1997; Kraus et al. 2007). In this study we analyzed the distribution of ionotropic non-NMDA receptors GluR2/3, one possible target for ganglionic glutamate. Immunohistochemistry in esophageal wholemounts showed GluR2/3-immunoreactivity (-ir) in nearly 30% of myenteric neurons. To determine the neuronal subpopulations which express GluR2/3 receptors, we per-formed NADPh-diaphorase histochemistry and combined GluR2/3 with nNOS- and ChAT- immunohistochemistry, respectively. Seventy-three % of myenteric neurons were nitrergic, 22% cholinergic and...

Research paper thumbnail of Neurotrophin-4 dependency of intraepithelial vagal sensory nerve terminals that selectively contact pulmonary NEBs in mice

Histology and histopathology, Aug 1, 2010

Important physiological functions of neurotrophins (NTs) in airways and lungs are the early devel... more Important physiological functions of neurotrophins (NTs) in airways and lungs are the early development, differentiation and maintenance of peripheral sensory neurons. The main pulmonary sensory innervation is of vagal origin, with several nerve fibre populations that selectively contact complex morphologically well-characterized receptor end-organs, called neuroepithelial bodies (NEBs). NEBs in mouse lungs are innervated by at least two separate myelinated vagal sensory nerve fibre populations, of which the neurochemical coding is suggestive of a mechanosensory function. Since neurotrophin-4 (NT-4) has been especially described to be important for the maintenance of mechanosensory nerve terminals, the present study aimed at investigating the NT-4 dependency of the two myelinated vagal sensory nerve fibre populations innervating mouse pulmonary NEBs. Multiple immunostaining in 21-day-old and adult mouse lungs revealed the expression of the NT-4 receptor TrkB on the two different mye...

Research paper thumbnail of Vesicular glutamate transporter 1 immunoreactivity in motor endplates of striated esophageal but not skeletal muscles in the mouse

Neuroscience Letters, 2004

Glutamate, the major excitatory transmitter in the central nervous system, has been speculated fo... more Glutamate, the major excitatory transmitter in the central nervous system, has been speculated for years to influence mammalian motor endplates but trials to identify glutamatergic motor terminals failed because specific markers were not available. Recently, antibodies to vesicular glutamate transporters (VGLUTs) opened new possibilities for further morphological investigations. We detected VGLUT1 immunoreactivity (-ir), but not VGLUT2-ir and VGLUT3-ir, respectively, in many motor nerve terminals in motor endplates of the mouse esophagus as identified by alpha-bungarotoxin or colocalization of VGLUT1 with choline acetyltransferase. These findings suggest that glutamate is co-stored with acetylcholine in esophageal neuromuscular junctions. Surprisingly, we found neither VGLUT1-ir nor VGLUT2-ir or VGLUT3-ir in neuromuscular junctions of somitic and branchiogenic skeletal muscles. This may reflect differences in functional properties and the embryonic origin between skeletal and esophageal striated muscle fibers.

Research paper thumbnail of Proline-rich synapse-associated protein-1 and 2 (ProSAP1/Shank2 and ProSAP2/Shank3)—scaffolding proteins are also present in postsynaptic specializations of the peripheral nervous system

Neuroscience, 2010

Proline-rich synapse-associated protein-1 and 2 (ProSAP1/Shank2 and ProSAP2/Shank3) were original... more Proline-rich synapse-associated protein-1 and 2 (ProSAP1/Shank2 and ProSAP2/Shank3) were originally found as synapse-associated protein 90/postsynaptic density protein-95-associated protein (SAPAP)/guanylate-kinase-associated protein (GKAP) interaction partners and also isolated from synaptic junctional protein preparations of rat brain. They are essential components of the postsynaptic density (PSD) and are specifically targeted to excitatory asymmetric type 1 synapses. Functionally, the members of the ProSAP/Shank family are one of the postsynaptic key elements since they link and attach the postsynaptic signaling apparatus, for example N-methyl-d-aspartic acid (NMDA)-receptors via direct and indirect protein interactions to the actin-based cytoskeleton. The functional significance of ProSAP1/2 for synaptic transmission and the paucity of data with respect to the molecular composition of PSDs of the peripheral nervous system (PNS) stimulated us to investigate neuromuscular junctions (NMJs), synapses of the superior cervical ganglion (SCG), and synapses in myenteric ganglia as representative synaptic junctions of the PNS. Confocal imaging revealed ProSAP1/2-immunoreactivity (-iry) in NMJs of rat and mouse sternomastoid and tibialis anterior muscles. In contrast, ProSAP1/2-iry was only negligibly found in motor endplates of striated esophageal muscle probably caused by antigen masking or a different postsynaptic molecular anatomy at these synapses. ProSAP1/2-iry was furthermore detected in cell bodies and dendrites of superior cervical ganglion neurons and myenteric neurons in esophagus and stomach. Ultrastructural analysis of ProSAP1/2 expression in myenteric ganglia demonstrated that ProSAP1 and ProSAP2 antibodies specifically labelled PSDs of myenteric neurons. Thus, scaffolding proteins ProSAP1/2 were found within the postsynaptic specializations of synapses within the PNS, indicating a similar molecular assembly of central and peripheral postsynapses.

Research paper thumbnail of Pitfalls using tyramide signal amplification (TSA) in the mouse gastrointestinal tract: Endogenous streptavidin-binding sites lead to false positive staining

Journal of Neuroscience Methods, 2012

Highly sensitive immunohistochemical detection systems such as tyramide signal amplification (TSA... more Highly sensitive immunohistochemical detection systems such as tyramide signal amplification (TSA) are widely used, since they allow using two primary antibodies raised in the same species. Most of them are based on the streptavidin-biotin-peroxidase system and include streptavidin-coupled secondary antibodies. Using TSA in cryostat-sectioned tissues of mouse esophagus, we were puzzled by negative controls with unexpected staining mostly in the ganglionic areas. This prompted us to search for the causing agent and to include also other parts of the mouse gastrointestinal tract for comparison. Streptavidin-coupled antibodies bound to endogenous binding sites yet to be characterized, which are present throughout the mouse intestines. Staining was mainly localized around neuronal cell bodies of enteric ganglia. Thus, caution is warranted when applying streptavidin-coupled antibodies in the mouse gastrointestinal tract. The use of endogenous biotin-blocking kits combined with a prolonged post-fixation time could significantly reduce unintentional staining.

Research paper thumbnail of Number and Distribution of Intraganglionic Laminar Endings in the Mouse Esophagus as Demonstrated with Two Different Immunohistochemical Markers

Journal of Histochemistry & Cytochemistry, 2005

Intraganglionic laminar endings (IGLEs) represent the only vagal mechanosensory terminals in the ... more Intraganglionic laminar endings (IGLEs) represent the only vagal mechanosensory terminals in the tunica muscularis of the esophagus. Two specific markers for IGLEs were recently described in mouse: the purinergic P2X2 receptor and the vesicular glutamate transporter 2 (VGLUT2). This study aimed at comparing both markers with respect to their suitability for quantitative analysis. We counted IGLEs immunostained for VGLUT2 and P2X2, respectively, and mapped their distribution in esophageal wholemounts of C57Bl/6 mice. Numbers and distribution of IGLEs were compared with those of myenteric ganglia as demonstrated by cuprolinic blue histochemistry. Whereas the distribution of VGLUT2-immunopositive IGLEs closely matched that of myenteric ganglia, P2X2-immunopositive IGLEs were rarely found in upper and middle esophagus but increasingly in its lower parts. P2X2 stained only half the number of IGLEs found with VGLUT2 immunostaining. We also investigated the correlation between anterograde ...

Research paper thumbnail of Localization of receptors for calcitonin-gene-related peptide to intraganglionic laminar endings of the mouse esophagus: peripheral interaction between vagal and spinal afferents?

Histochemistry and Cell Biology, 2013

The calcitonin gene-related peptide (CGRP)-receptor is a heterodimer of calcitonin receptorlike r... more The calcitonin gene-related peptide (CGRP)-receptor is a heterodimer of calcitonin receptorlike receptor (CLR) and receptor activity modifying protein 1 (RAMP1). Despite the importance of CGRP in regulating gastrointestinal functions, nothing is known about the distribution and function of CLR/RAMP1 in the esophagus, where up to 90% of spinal afferent neurons contain CGRP. We detected CLR/RAMP1 in the mouse esophagus using immunofluorescence and confocal laser scanning microscopy and examined their relationship with neuronal elements of the myenteric plexus. Immunoreactivity for CLR and RAMP1 colocalized with VGLUT2-positive IGLEs, which were contacted by CGRP-positive varicose axons presumably of spinal afferent origin, typically at sites of CRL/ RAMP1 immunoreactivity. This provides an anatomical basis for interaction between spinal afferent fibres and IGLEs. Immunoreactive CLR and RAMP1 also colocalized in myenteric neurons. Thus, CGRP-containing spinal afferents may interact with both vagal IGLEs and myenteric neurons in the mouse esophagus, possibly modulating motility reflexes and inflammatory hypersensitivity.

Research paper thumbnail of Quantitative evaluation of neurons in the mucosal plexus of adult human intestines

Histochemistry and Cell Biology, 2011

Research paper thumbnail of Distribution of P2X3 receptor immunoreactivity in myenteric ganglia of the mouse esophagus

Histochemistry and Cell Biology, 2008

Intraganglionic laminar endings (IGLEs) represent the major vagal afferent terminals throughout t... more Intraganglionic laminar endings (IGLEs) represent the major vagal afferent terminals throughout the gut. Electrophysiological experiments revealed a modulatory role of ATP in the IGLE-mechanotransduction process and the P2X(2)-receptor has been described in IGLEs of mouse, rat and guinea pig. Another purinoceptor, the P2X(3)-receptor, was found in IGLEs of the rat esophagus. These findings prompted us to investigate occurrence and distribution of the P2X(3)-receptor in the mouse esophagus. Using multichannel immunofluorescence and confocal microscopy, P2X(3)-immunoreactivity (-iry) was found colocalized with the vesicular glutamate transporter 2 (VGLUT2), a specific marker for IGLEs, on average in three-fourths of esophageal IGLEs. The distribution of P2X(3) immunoreactive (-ir) IGLEs was similar to that of P2X(2)-iry and showed increasing numbers towards the abdominal esophagus. P2X(3)/P2X(2)-colocalization within IGLEs suggested the occurrence of heteromeric P2X(2/3) receptors. In contrast to the rat, where only a few P2X(3)-ir perikarya were described, P2X(3) stained perikarya in ~80% of myenteric ganglia in the mouse. Detailed analysis revealed P2X(3)-iry in subpopulations of nitrergic (nNOS) and cholinergic (ChAT) myenteric neurons and ganglionic neuropil of the mouse esophagus. We conclude that ATP might act as a neuromodulator in IGLEs via a (P2X(2))-P2X(3) receptor-mediated pathway especially in the abdominal portion of the mouse esophagus.

Research paper thumbnail of Vesicular glutamate transporter 1 immunoreactivity in extrinsic and intrinsic innervation of the rat esophagus

Histochemistry and Cell Biology, 2005

Encouraged by the recent finding of vesicular glutamate transporter 2 (VGLUT2) immunoreactivity (... more Encouraged by the recent finding of vesicular glutamate transporter 2 (VGLUT2) immunoreactivity (-ir) in intraganglionic laminar endings (IGLEs) of the rat esophagus, we investigated also the distribution and co-localization patterns of VGLUT1. Confocal imaging revealed substantial co-localization of VGLUT1-ir with selective markers of IGLEs, i.e., calretinin and VGLUT2, indicating that IGLEs contain both VGLUT1 and VGLUT2 within their synaptic vesicles. Besides IGLEs, we found VGLUT1-ir in both cholinergic and nitrergic myenteric neuronal cell bodies, in fibers of the muscularis mucosae, and in esophageal motor endplates. Skeletal neuromuscular junctions, in contrast, showed no VGLUT1-ir. We also tested for probable co-localization of VGLUT1-ir with markers of extrinsic and intrinsic esophageal innervation and glia. Within the myenteric neuropil we found, besides co-localization of VGLUT1 and substance P, no further co-localization of VGLUT1-ir with any of these markers. In the muscularis mucosae some VGLUT1-ir fibers were shown to contain neuronal nitric oxide synthase (nNOS)-ir. VGLUT1-ir in esophageal motor endplates was partly co-localized with vesicular acetylcholine transporter (VAChT)/choline acetyltransferase (ChAT)-ir, but VGLUT1-ir was also demonstrated in separately terminating fibers at motor endplates co-localized neither with ChAT/VAChT-ir nor with nNOS-ir, suggesting a hitherto unknown glutamatergic enteric co-innervation. Thus, VGLUT1-ir was found in extrinsic as well as intrinsic innervation of the rat esophagus.

Research paper thumbnail of Intraganglionic laminar endings and their relationships with neuronal and glial structures of myenteric ganglia in the esophagus of rat and mouse

Histochemistry and Cell Biology, 2000

Intraganglionic laminar endings (IGLEs) represent the only vagal mechanosensory terminals in the ... more Intraganglionic laminar endings (IGLEs) represent the only vagal mechanosensory terminals in the tunica muscularis of the esophagus and may be involved in local reflex control. We recently detected extensive though not complete colocalization of the vesicular glutamate transporter 2 (VGLUT2) with markers for IGLEs. To elucidate this colocalization mismatch, this study aimed at identifying markers for nitrergic, cholinergic, peptidergic, and adrenergic neurons and glial cells, which may colocalize with VGLUT2 outside of IGLEs. Confocal imaging revealed, besides substantial colocalization of VGLUT2 and substance P (SP), no other significant colocalizations of VGLUT2 and immunoreactivity for any of these markers within the same varicosities. However, we found close contacts of VGLUT2-positive structures to vesicular acetylcholine transporter, choline acetyltransferase, neuronal nitric oxide synthase, galanin, neuropeptide Y, and vasoactive intestinal peptide immunoreactive cell bodies and varicosities, as well as to glial cells. Neuronal perikarya were never positive for VGLUT2. Thus, VGLUT2 was almost exclusively found in IGLEs and may serve as a specific marker for them. In addition, many IGLEs also contained SP. The close contacts established by IGLEs to myenteric cell bodies, dendrites, and varicose fibers suggest that IGLEs modulate various types of enteric neurons and vice versa.

Research paper thumbnail of Surgery of a splenic artery aneurysm during pregnancy

European Journal of Obstetrics & Gynecology and Reproductive Biology, 2002

We report a case of ligation of the splenic artery with splenectomy during pregnancy due to a spl... more We report a case of ligation of the splenic artery with splenectomy during pregnancy due to a splenic artery aneurysm. The risk of aneurysmal rupture is increased in multipara and during pregnancy. As a result of high maternal and fetal morbidity and mortality elective surgery should be performed.

Research paper thumbnail of Muscarinic acetylcholine receptors in the mouse esophagus: focus on vagal intraganglionic laminar endings (IGLEs)

Autonomic Neuroscience, 2013

ABSTRACT IGLEs represent the only low-threshold vagal mechanosensory terminals in the tunica musc... more ABSTRACT IGLEs represent the only low-threshold vagal mechanosensory terminals in the tunica muscularis of the esophagus. Previously, close relationships of vesicular glutamate transporter 2 (VGLUT2) immunopositive IGLEs and cholinergic varicosities suggestive for direct contacts were described in almost all mouse esophageal myenteric ganglia. Possible cholinergic influence on IGLEs requires specific acetylcholine receptors. In particular, the occurrence and location of neuronal muscarinic acetylcholine receptors (mAChR) in the esophagus were not yet characterized. This study aimed at specifying relationships of VGLUT2 immunopositive IGLEs and vesicular acetylcholine transporter (VAChT)-immunopositive varicosities using preembedding electron microscopy and the location of mAChR1-3 (M1-3) within esophagus and nodose ganglia using multilabel immunofluorescence and retrograde tracing. Electron microscopy confirmed synaptic contacts between cholinergic varicosities and IGLEs. M1- and M2-immunoreactivity (-iry) was colocalized with VGLUT2-iry in subpopulations of IGLEs. Retrograde Fast Blue tracing from the esophagus showed nodose ganglion neurons colocalizing tracer and M2-iry. Acetylcholine probably released from varicosities of both extrinsic and intrinsic origin may influence a subpopulation of esophageal IGLEs via M2 and M1 receptors. (Supported by Johannes und Frieda Marohn-Stiftung, Erlangen).