title: Cytoplasmic, but not nuclear, expression of the neuronal nuclei (NeuN) antibody is an exclusive feature of Dogiel type II neurons in the guinea-pig gastrointestinal tract.
abstract: This study aimed to reveal if NeuN, a neuronal nuclei (NeuN) antibody, is a selective marker of intrinsic primary afferent neurons (IPANs) in the guinea-pig gastrointestinal tract as previously hypothesised. The NeuN immunoreactivity was found in the enteric nervous system with exception of the esophagus. Two groups of NeuN-expressing neurons were observed: neurons with immunostained nuclei and cytoplasm (NeuN(NC)) and neurons only expressing immunoreactivity in their nuclei (NeuN(N)). The NeuN(N)-immunoreactive neurons were found in the myenteric plexus of the stomach and the colon. In the stomach, none of the NeuN(N)-expressing neurons, of which 55+/-3% co-expressed calbindin, had a Dogiel type I or II morphology. The NeuN(N)-positive neurons of the colon, which did not express calbindin, did not resemble a Dogiel type II morphology either, but were small-sized neurons. The NeuN(NC)-immunoreactive neurons were observed in both the small and large intestine. These neurons were smooth-contoured and bigger-sized, resembling a Dogiel type II morphology. Some of these neurons co-expressed calbindin. The present data reveal the existence of two populations of Dogiel type II neurons, exhibiting NeuN(NC)+/calbindin+ or NeuN(NC)+/calbindin- immunoreactivity, in the intestine. Assuming that all IPANs exhibit a Dogiel type II morphology, we conclude that the cytoplasmic expression of NeuN is an exclusive feature of IPANs.
authors.affiliation: Laboratory of Cell Biology and Histology, University of Antwerp, Groenenborgerlaan 171, 2020, Antwerp, Belgium.
authors.forename: Luc
authors.initials: L
authors.lastname: Van Nassauw
authors.forename: Mei
authors.initials: M
authors.lastname: Wu
authors.forename: Frederik
authors.initials: F
authors.lastname: De Jonge
authors.forename: Dirk
authors.initials: D
authors.lastname: Adriaensen
authors.forename: Jean-Pierre
authors.initials: JP
authors.lastname: Timmermans
mesh_terms: D000818:Animals; D015415:Biomarkers / Q000378:metabolism; D002467:Cell Nucleus / Q000378:metabolism*; D003593:Cytoplasm / Q000378:metabolism*; D004268:DNA-Binding Proteins; D005260:Female; D041981:Gastrointestinal Tract / Q000294:innervation*; D006168:Guinea Pigs; D008297:Male; D009197:Myenteric Plexus / Q000166:cytology / Q000378:metabolism*; D009419:Nerve Tissue Proteins / Q000276:immunology / Q000378:metabolism*; D009474:Neurons / Q000145:classification / Q000166:cytology / Q000378:metabolism*; D009687:Nuclear Proteins / Q000276:immunology
chemical_list: D015415:Biomarkers; D004268:DNA-Binding Proteins; D009419:Nerve Tissue Proteins; C492380:NeuN protein, mouse; D009687:Nuclear Proteins