Origins and projections of nerve fibres in rat pyloric sphincter.
Author
Summary, in English
Nerve fibres play an important role in the regulation of gastric emptying. The aims of this study were to clarify the distribution, projections and origin of neuronal type nitric oxide synthase (NOS)-, tyrosine hydroxylase (TH)-, vesicular acetylcholine transporter (VAchT)- and peptide-containing nerve fibres of the rat pyloric sphincter. Extrinsic and local denervations of the sphincter were performed in order to reveal the origin and projections of the various nerve fibre populations. Pylorus from control and denervated animals were processed for the immunocytochemical demonstration of cholecystokinin (CCK), enkephalin, gastrin-releasing peptide (GRP), somatostatin, calcitonin gene-related peptide (CGRP), neuropeptide Y (NPY), pituitary adenylate cyclase-activating peptide (PACAP), substance P (SP), vasoactive intestinal peptide (VIP), galanin, NOS, VAchT and TH. VAchT, TH, nNOS, and all of the peptides investigated were found in nerve fibres innervating the pyloric sphincter, and coexistence of several putative neurotransmitters were revealed. Extrinsic denervation caused a total loss of NPY/TH-, SP/CGRP- and SP/CGRP/VIP/NOS/PACAP-containing nerve fibres. Local denervation immediately proximal to the sphincter markedly reduced the numbers of VIP/NOS/galanin- and VIP/NOS/galanin/PACAP +/- NPY-containing fibres within the sphincter suggesting an origin of these fibres in myenteric ganglia in the antral region; denervation at the level of the oxyntic-pyloric border had no effect. Local denervation immediately distal to the sphincter caused a marked decrease in VAchT-, SP/enkephalin-, enkephalin-, somatostatin-, CCK- and GRP-containing fibres within the sphincter suggesting that these emanate from the duodenum. The latter procedure also reduced the number of SP/CGRP-containing fibres of extrinsic origin within the pyloric sphincter.
Department/s
Publishing year
2002
Language
English
Pages
73-82
Publication/Series
Autonomic Neuroscience: Basic & Clinical
Volume
97
Issue
2
Document type
Journal article
Publisher
Elsevier
Topic
- Cell and Molecular Biology
Keywords
- Neuropeptides
- Nitric oxide synthase
- Tyrosine hydroxylase
- Vesicular acetylcholine transporter
- Enteric nervous system
- Pylorus
Status
Published
ISBN/ISSN/Other
- ISSN: 1872-7484