The Distribution and Chemical Coding of Intramural Neurons Supplying the Porcine Stomach – the Study on Normal Pigs and on Animals Suffering from Swine Dysentery

Abstract

The present study was designed to investigate the expression of biologically active substances by intramural neurons supplying the stomach in normal (control) pigs and in pigs suffering from dysentery. Eight juvenile female pigs were used. Both dysenteric (n = 4; inoculated with Brachyspira hyodysenteriae) and control (n = 4) animals were deeply anaesthetized, transcardially perfused with buffered paraformalehyde, and tissue samples comprising all layers of the wall of the ventricular fundus were collected. The cryostat sections were processed for double-labelling immunofluorescence to study the distribution of the intramural nerve structures (visualized with antibodies against protein gene-product 9.5) and their chemical coding using antibodies against vesicular acetylcholine (ACh) transporter (VAChT), nitric oxide synthase (NOS), galanin (GAL), vasoactive intestinal polypeptide (VIP), somatostatin (SOM), Leu(5)-enkephalin (LENK), substance P (SP) and calcitonin gene-related peptide (CGRP). In both inner and outer submucosal plexuses of the control pigs, the majority of neurons were SP (55% and 58%, respectively)- or VAChT (54%)-positive. Many neurons stained also for CGRP (43 and 45%) or GAL (20% and 18%) and solitary perikarya were NOS-, SOM- or VIP-positive. The myenteric plexus neurons stained for NOS (20%), VAChT (15%), GAL (10%), VIP (7%), SP (6%) or CGRP (solitary neurons), but they were SOM-negative. No intramural neurons immunoreactive to LENK were found. The most remarkable difference in the chemical coding of enteric neurons between the control and dysenteric pigs was a very increased number of GAL- and VAChT-positive nerve cells (up to 61% and 85%, respectively) in submucosal plexuses of the infected animals. The present results suggest that GAL and ACh have a specific role in local neural circuits of the inflamed porcine stomach in the course of swine dysentery.

The Influence of Low Doses of Zearalenone and T-2 Toxin on Calcitonin Gene Related Peptide-Like Immunoreactive (CGRP-LI) Neurons in the ENS of the Porcine Descending Colon

“…Two facts confirm this supposition. Firstly, it is well known that the expression of neuroprotective factors in the ENS increases during pathological processes [5,6,42,43], and the growth of CGRP-like immunoreactivity has been observed during both the present study and in previous investigations on other fragments of the digestive tract [44]. Secondly, CGRP affects the release of nitric oxide, whose neuroprotective activity is relatively well surveyed [45,46,47].…”

Localization and neurochemical characteristics of the extrinsic sympathetic neurons projecting to the pylorus in the domestic pig

“…Previous experiments on the innervation of the swine gastrointestinal tract have focused mainly on the extrinsic innervation of the small intestine (Kaleczyc et al, 2004;Pidsudko et al, 2011), large intestine (Pidsudko et al, 2001;Skobowiat et al, 2010aSkobowiat et al, ,b, 2011 and the intrinsic innervation of the different parts of the digestive tract (Barbiers et al, 1993b;Kaleczyc et al, 2007;Melander et al, 1985;Porcher et al, 2000;Scheuermann and Stach, 1984;Timmermans et al, 1990;Van Ginneken et al, 1996). The precise localization and chemical coding of the extrinsic sympathetic perikarya innervating the porcine pylorus still remain unknown.…”

Zinc Transporter 3 (ZnT3) in the Enteric Nervous System of the Porcine Ileum in Physiological Conditions and during Experimental Inflammation

“…Besides acetylcholine, which is the main transmitter in enteric neurons [5,6], several dozen other neuronal active substances have been described within the ENS [2,3]. The most important of these include, among others, vasoactive intestinal peptide (VIP), galanin (GAL), neuronal isoform of nitric oxide synthase (nNOS) and substance P (SP) [7,8,9]. Most of the abovementioned factors act as neuromediators and/or neuromodulators, but the functions of some neuronal substances described in the ENS remain unknown.…”