Get access

Chemical coding of the human gastrointestinal nervous system: Cholinergic, VIPergic, and catecholaminergic phenotypes

Authors

  • Martin Anlauf,

    1. Department of Molecular Neuroscience, Institute of Anatomy and Cell Biology, Philipps University, Marburg, 35037 Marburg, Germany
    2. Department of Pathology, University of Kiel, 24105 Kiel, Germany
    Search for more papers by this author
  • Martin K.-H. Schäfer,

    1. Department of Molecular Neuroscience, Institute of Anatomy and Cell Biology, Philipps University, Marburg, 35037 Marburg, Germany
    Search for more papers by this author
  • Lee Eiden,

    1. Section on Molecular Neuroscience, Laboratory of Cellular and Molecular Regulation, National Institute of Mental Health, NIHM, Bethesda, Maryland 20892
    Search for more papers by this author
  • Eberhard Weihe

    Corresponding author
    1. Department of Molecular Neuroscience, Institute of Anatomy and Cell Biology, Philipps University, Marburg, 35037 Marburg, Germany
    • Dept. of Molecular Neuroscience, Institute of Anatomy and Cell Biology, Philipps University, Robert-Koch Strasse 6, 35037 Marburg, Germany
    Search for more papers by this author

Abstract

The aim of this investigation was to identify the proportional neurochemical codes of enteric neurons and to determine the specific terminal fields of chemically defined nerve fibers in all parts of the human gastrointestinal (GI) tract. For this purpose, antibodies against the vesicular monoamine transporters (VMAT1/2), the vesicular acetylcholine transporter (VAChT), tyrosine hydroxylase (TH), dopamine β-hydroxylase (DBH), serotonin (5-HT), vasoactive intestinal peptide (VIP), and protein gene product 9.5 (PGP 9.5) were used. For in situ hybridization 35S-labeled VMAT1, VMAT2, and VAChT riboprobes were used. In all regions of the human GI tract, 50–70% of the neurons were cholinergic, as judged by staining for VAChT. The human gut unlike the rodent gut exhibits a cholinergic innervation, which is characterized by an extensive overlap with VIPergic innervation. Neurons containing VMAT2 constituted 14–20% of all intrinsic neurons in the upper GI tract, and there was an equal number of TH-positive neurons. In contrast, DBH was absent from intrinsic neurons. Cholinergic and monoaminergic phenotypes proved to be completely distinct phenotypes. In conclusion, the chemical coding of human enteric neurons reveals some similarities with that of other mammalian species, but also significant differences. VIP is a cholinergic cotransmitter in the intrinsic innervation of the human gut. The substantial overlap between VMAT2 and TH in enteric neurons indicates that the intrinsic catecholaminergic innervation is a stable component of the human GI tract throughout life. The absence of DBH from intrinsic catecholaminergic neurons indicates that these neurons have a dopaminergic phenotype. J. Comp. Neurol. 459:90–111, 2003. © 2003 Wiley-Liss, Inc.

Get access to the full text of this article

Ancillary