Vasculogenesis by Endothelial Progenitor Cells In Vitro

The present study investigated the arrangement and chemical coding of intramural nerve structures supplying the porcine stomach. Tissue samples comprising all layers of the wall of the ventricular fundus were collected from juvenile female pigs ( n  = 4), which were first deeply anaesthetized and then transcardially perfused with buffered paraformaldehyde. 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 neurochemical characteristics using antibodies against vesicular acetylcholine transporter (VAChT), nitric oxide synthase (NOS), galanin (GAL), vasoactive intestinal-polypeptide (VIP), somatostatin (SOM) and substance P (SP). The study confirmed the presence of three distinct nerve plexuses within the wall of the porcine stomach including one myenteric plexus and two, outer and inner, submucous plexuses. The outer and inner submucous plexuses (OSP and ISP, respectively) were similar in respect to the chemical coding of neurons they contained. Most of the neurons expressed immunoreactivity to SP (ISP 58%; OSP 60%) or to VAChT (ISP 56%; OSP 56%), some of them stained for GAL (ISP 18%; OSP 15%) and solitary nerve cells were SOM-positive (in ISP only). No neurons in the submucous plexuses displayed immunoreactivity to VIP or NOS. In the myenteric plexus, some neurons stained for NOS (20%), VAChT (15%), GAL (10%), VIP (8%) or SP (8%) while no neurons immunoreactive for SOM were encountered. In both submucous and myenteric plexuses, many varicose nerve fibres expressed immunoreactivity to VAChT, GAL or SP, while VIP-, SOM- or NOS-positive nerve terminals were less numerous. The comparison of the present results with those obtained by other authors has revealed distinct inter-species differences regarding the arrangement and chemical coding of nerve structures supplying the mammalian stomach.     

The Distribution and Chemical Coding of Intramural Nerve Structures Supplying the Porcine Stomach

The present study investigated the arrangement and chemical coding of intramural nerve structures supplying the porcine stomach. Tissue samples comprising all layers of the wall of the ventricular fundus were collected from juvenile female pigs (n = 4), which were first deeply anaesthetized and then transcardially perfused with buffered paraformaldehyde. 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 neurochemical characteristics using antibodies against vesicular acetylcholine transporter (VAChT), nitric oxide synthase (NOS), galanin (GAL), vasoactive intestinal‐polypeptide (VIP), somatostatin (SOM) and substance P (SP). The study confirmed the presence of three distinct nerve plexuses within the wall of the porcine stomach including one myenteric plexus and two, outer and inner, submucous plexuses. The outer and inner submucous plexuses (OSP and ISP, respectively) were similar in respect to the chemical coding of neurons they contained. Most of the neurons expressed immunoreactivity to SP (ISP 58%; OSP 60%) or to VAChT (ISP 56%; OSP 56%), some of them stained for GAL (ISP 18%; OSP 15%) and solitary nerve cells were SOM‐positive (in ISP only). No neurons in the submucous plexuses displayed immunoreactivity to VIP or NOS. In the myenteric plexus, some neurons stained for NOS (20%), VAChT (15%), GAL (10%), VIP (8%) or SP (8%) while no neurons immunoreactive for SOM were encountered. In both submucous and myenteric plexuses, many varicose nerve fibres expressed immunoreactivity to VAChT, GAL or SP, while VIP‐, SOM‐ or NOS‐positive nerve terminals were less numerous. The comparison of the present results with those obtained by other authors has revealed distinct inter‐species differences regarding the arrangement and chemical coding of nerve structures supplying the mammalian stomach.     

The influence of experimental ileitis on the neuropeptide coding of enteric neurons in the pig

In the present study, both the ELISA test and immunohistochemical staining were used to investigate the influence of artificially induced ileitis on the chemical coding of enteric neurons in the pig. The ileum wall in experimental (E) pigs was injected in multiple sites with 4% paraformaldehyde to induce inflammation, while in the control (C) animals, the organ was injected with 0.1M phosphate buffer (pH 7.4). Three days after ileitis induction, samples of ileum wall from all the animals were evaluated for VIP, SP, CGRP, NPY, GAL and SOM concentration (ELISA test) and the expression of these biologically active substances by the enteric neurons (immunohistochemical staining). Quantitative results showed that ileitis decreased tissue concentration of VIP, CGRP and SOM but increased tissue concentration of SP, NPY and GAL. Immunochemistry revealed that in both the experimental and control pigs, VIP-positive (VIP+) nerve fibers supplied mainly ileal blood vessels, and the labeled pericarya were located in the inner (ISP) and outer submucous plexus (OSP). SP+ and CGRP+ nerve terminals were found in both the mucous and muscular membrane, while the labeled pericarya were found in ISP, OSP and myenteric plexus (MP). In both C and E pigs, the very few nerve terminals containing NPY and SOM were located mainly in the mucous membrane. NPY- or/and SOM-immunopositive nerve cell bodies were found in ISP, OSP and MP. GAL+ nerve fibers supplied all layers of the ileum and were most numerous in the muscular membrane, while the labeled pericarya were present in all the enteric plexuses. The present results suggest that enteric neurons are highly plastic in their response to inflammation.     

GAL‐ and VIP‐Immunoreactive Nerve Structures in the Ileum and Large Intestine of Pigs with Dysentery

The morphology, neurochemistry and function of intramural nerve structures in the mammalian gastrointestinal tract are relatively well known, but in normal, healthy individuals. The present study was aimed at investigating the chemical coding of nerve structures in the wall of the ileum and large intestine in normal pigs (n = 3) and in pigs undergoing dysentery (n = 6). Dysentery was evoked by artificial infection of the clinically healthy animals per os with Brachyspira hyodysenteriae. All the animals were deeply anaesthetized and transcardially perfused with 4% paraformaldehyde. The cryostat sections of the intestines were processed for double‐labelling immunohistochemistry using antisera against PGP 9.5, GAL and VIP. In the intramural plexuses of the control pigs, the percentage of GAL‐immunoreactive (GAL‐IR) perykarya varied from 11% (descending colon) to 19% (centrifugal turns of the ascending colon) whereas in the dysenteric pigs, it was distinctly higher, reaching from 28% (ileum) up to 48% (cecum). In the control animals, the percentage of VIP‐IR neuronal somata varied from 3% (descending colon) to 19% (ileum). In dysenteric pigs, it was from 6% (descending colon) up to 28% (cecum). In the muscular coat (MC) and mucous membrane (MM) of the normal intestine, very numerous GAL‐ and VIP‐IR nerve fibres were observed. The nerve fibres in the myenteric plexus (MP) were even more numerous than those in the muscular coat while in the outer (OSP) and inner (ISP) submucous plexuses, they were less abundant. In the dysenteric pigs, the nerve fibres found in MC, MP and OSP were less numerous, whereas those observed in ISP and MM were more abundant than those in the control animals. The present results suggest that GAL and VIP are involved in the regulation of inflammatory processes developing in the porcine gastrointestinal tract during dysentery.     

Fractures of Ossified Rib Cartilages in the Horse – a Concern of Veterinarians?

The morphology, neurochemistry and function of intramural nerve structures in the mammalian gastrointestinal tract are relatively well known, but in normal, healthy individuals. The present study was aimed at investigating the chemical coding of nerve structures in the wall of the ileum and large intestine in normal pigs ( n  = 3) and in pigs undergoing dysentery ( n  = 6). Dysentery was evoked by artificial infection of the clinically healthy animals per os with Brachyspira hyodysenteriae . All the animals were deeply anaesthetized and transcardially perfused with 4% paraformaldehyde. The cryostat sections of the intestines were processed for double-labelling immunohistochemistry using antisera against PGP 9.5, GAL and VIP. In the intramural plexuses of the control pigs, the percentage of GAL-immunoreactive (GAL-IR) perykarya varied from 11% (descending colon) to 19% (centrifugal turns of the ascending colon) whereas in the dysenteric pigs, it was distinctly higher, reaching from 28% (ileum) up to 48% (cecum). In the control animals, the percentage of VIP-IR neuronal somata varied from 3% (descending colon) to 19% (ileum). In dysenteric pigs, it was from 6% (descending colon) up to 28% (cecum). In the muscular coat (MC) and mucous membrane (MM) of the normal intestine, very numerous GAL- and VIP-IR nerve fibres were observed. The nerve fibres in the myenteric plexus (MP) were even more numerous than those in the muscular coat while in the outer (OSP) and inner (ISP) submucous plexuses, they were less abundant. In the dysenteric pigs, the nerve fibres found in MC, MP and OSP were less numerous, whereas those observed in ISP and MM were more abundant than those in the control animals. The present results suggest that GAL and VIP are involved in the regulation of inflammatory processes developing in the porcine gastrointestinal tract during dysentery.     

The distribution and chemical coding of intramural neurons supplying the porcine stomach - the study on normal pigs and on animals suffering from swine dysentery

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.     

Structural and functional components of the feline enteric nervous system

Neurohistological and immunohistochemical examinations of the feline enteric nervous system (ENS) were performed by using antibodies against neuron-specific enolase (NSE), phosphorylated neurofilaments (PN), non-phosphorylated neurofilaments (NPN) and vasoactive intestinal peptide (VIP), whereas glial cells were investigated by using antibodies against glial fibrillary acidic protein (GFAP). The study included full-thickness biopsies of the stomach, duodenum, jejunum, ileum and colon of 11 healthy cats. In this study, immunohistochemical staining of feline ENS with antibodies to NSE, PN and NPN revealed the presence of different ganglionated and aganglionated plexus. The two ganglionated plexus were arranged in a plexus submucosus internus & externus and a plexus myentericus. Furthermore, plexus mucosus and subserosal plexus represented two aganglionated plexus. GFAP-stained cellular elements were smaller than and in close contact to enteric neurons possibly resembling astrocytes of the central nervous system. VIP is one of the major neurotransmitters of enteric inhibitory neurons, and immunoreactivity was present in all layers of the gut, especially in ganglionated plexus. This is the first report, describing feline ENS by using immunohistochemical methods.     

不同日龄仔猪小肠黏膜下神经丛神经元类型变化的研究

采用组织化学和免疫组织化学的方法对0、5、28日龄的仔猪小肠黏膜下神经丛中神经元类型的变化进行了定性研究和定量测定。结果表明，仔猪小肠黏膜下神经丛分为靠近环肌层表面的ESP(external submucosal plexus)和靠近黏膜肌层的ISP(internal submucosal plexus)；ESP与ISP神经纤维的性质不同，ESP主要是有髓神经纤维，而ISP主要是无髓神经纤维；随着日龄增长，黏膜下神经丛发育较快，ESP与ISP的差异日益显著。研究揭示：仔猪出生后黏膜下神经丛在形态和不同亚群神经元比例上均有一调整期，其生理学意义可能是使小肠黏膜下神经丛的功能日益完善。     

Galanin is Co‐Expressed with Substance P,Calbindin and Corticotropin‐Releasing Factor (CRF) in The Enteric Nervous System of the Wild Boar (Sus scrofa) Small Intestine

Galanin is a neuropeptide widely present in the enteric nervous system of numerous animal species and exhibiting neurotransmittery/neuromodulatory roles. Colocalization patterns of galanin with substance P (SP), corticotropin‐releasing factor (CRF) and calbindin were studied in the small intestine of the wild boar using immunofluorescence technique. We demonstrated the presence of SP in substantial populations of galanin‐immunoreactive (IR) submucous neurons. Additionally, different amounts of nerve fibres exhibiting simultaneous presence of galanin and SP were noted in the small intestinal smooth musculature, submucous ganglia, lamina muscularis mucosae and mucosa. In the wild boar duodenum, jejunum and ileum, the co‐expression of galanin and calbindin was limited to minor populations of submucous neurons only. Single galanin‐/CRF‐IR nerve fibres were exclusively present in the duodenal and jejunal (but not ileal) mucosa. These results strongly suggest that galanin participates in neuronal control of the wild boar small intestine also by functional co‐operation with other biologically active neuropeptides.     

Immunohistochemical study of the otic ganglion in the pig

The presence of choline acetyltransferase (ChAT), vesicular acetylcholine transporter (VAChT), neuropeptide Y (NPY), vasoactive intestinal polypeptide (VIP), somatostatin (SOM), galanin (GAL), substance P (SP) and calcitonin gene-related peptide (CGRP) was studied in neurons and nerve fibers of the porcine otic ganglion. ChAT-positive neurons were very numerous while VAChT-positive nerve cells were moderate in number. The number of neurons containing NPY and VIP was lower and those containing SOM, GAL, SP or CGRP were observed as scarce, or single nerve cells. The above mentioned substances (except SOM) were present in nerve fibers of the ganglion. ChAT- and VAChT-positive nerve fibers were numerous, while the number of nerve terminals containing NPY, VIP and SP was lower. GAL- and CGRP-positive nerve fibers were scarce.     

Comparative study of the distribution of NOS-positive neurons in pigeon intestine

Nitric oxide (NO) plays an important role in regulating gut motility, mucosal barrier function and secretions in the enteric nervous system. Nicotinamide adenine dinucleotide phosphate diaphorase (NADPH-d) staining has been used to identify nitrergic neurons of the enteric nervous system in different species. However, NADPH-d staining lacks specificity because it also reflects the presence of enzymes other than nitric oxide synthase (NOS). Therefore, NOS immunohistochemistry techniques are needed to test for nitrergic neurons in the avian gut. In the present work, the morphology, density and size of NOS-positive neurons in the duodenum, jejunum, ileum, caecum and rectum myenteric plexus of adult pigeons were investigated using NOS immunohistochemistry and whole-mount preparations techniques. The density of NOS-positive ganglion was highest in the ileum, similar to the caecum and rectum, and the lowest staining levels were observed in the duodenum. The staining intensity of NOS-positive neurons in the duodenum, jejunum and ileum was dark, followed by the rectal regions, with weak staining in the caecum. These results suggested that NOS immunohistochemistry and whole-mount preparation techniques provide an effective assessment method of the ganglia in the pigeon intestinal myenteric nerve plexus and are more accurate for cell counting compared with conventional sections.     

Infection of the enteric nervous system by Borna disease virus (BDV) upregulates expression of Calbindin D-28k

Borna disease virus (BDV) is a neurotropic agent infecting distinct neuronal subpopulations in the central nervous system of various mammalian species possibly including humans. Horses, a major natural host for BDV, show gastrointestinal dysfunctions besides characteristic neurological symptoms. Therefore, we hypothesized that enteric neurons may be targets of BDV replication. The presence of BDV-specific antigen in subpopulations of the ENS was investigated. Four-week-old Lewis rats were infected intracerebrally and sacrificed 4-14 weeks post infection (p.i.). BDV-immunoreactive neurons were found in submucous and myenteric neurons of the proximal colon. Fourteen weeks p.i., the proportion of BDV-positive neurons was 44+/-17 and 24+/-7% in the submucous and myenteric plexus, respectively. The majority of BDV-positive myenteric neurons showed immunoreactivity for choline acetyltransferase. Expression of Calbindin D-28k (CALB) was found in 96% of submucous and 67% of myenteric BDV-immunoreactive neurons. Additionally, the number of CALB-immunoreactive neurons was significantly higher in the myenteric plexus of infected rats compared to controls. These data indicate that BDV infects specific subpopulations of enteric neurons. Therefore, the ENS might serve as a site for BDV replication and as an immunoprivileged reservoir for BDV. In addition, upregulation of CALB in neurons of the myenteric plexus is probably induced during BDV-infection.     

Modulation of electrogenic transport processes in the porcine proximal colon by enteric neurotransmitters

The aim of our study was to evaluate the involvement of essential pro- and antisecretory neurotransmitters in regulation of secretion in porcine proximal colon. Choline acetyltransferase (ChAT), nitric oxide synthase (NOS), vasoactive intestinal peptide (VIP), substance P (SP), somatostatin (SOM) and neuropeptide Y (NPY) were located immunohistochemically in the epithelium and subepithelial layer. Modulation of epithelial secretion was studied in Ussing chambers. Application of carbachol (CA), sodium nitroprussid (SNP), VIP and SP but not of NPY or SOM resulted in a chloride dependent increase in short circuit current (I(sc) ). I(sc) increase induced by CA, VIP or SNP was not altered by preincubation with tetrodotoxin or indomethacin. In contrast, SP-induced I(sc) increase was diminished by preincubation with tetrodotoxin, indomethacin, L-nitro-arginin-methyl-ester, and atropine but not hexamethonium. Simultaneous application of CA and VIP, or CA and SNP increased the I(sc) stronger as expected. Applying SP/CA led to a smaller increase in I(sc) as calculated. It is concluded that mainly prosecretory neurotransmitters are involved in regulation of colonic secretion. Cross-potentiations of acetylcholine and nitric oxide and acetylcholine and VIP suggest activation of different intracellular cascades. Similar intracellular pathways may be stimulated by acetylcholine and SP, thus preventing an additive effect of the transmitters.     

Immunohistochemical study of the pre- and postnatal innervation of the dog lower urinary tract: morphological aspects at the basis of the consolidation of the micturition reflex

Immunohistochemical studies were performed on male and female bladder and urethra collected from 4 adults dogs and 10 foetal specimens with crown-rump length from 53 to 155 mm (medium-sized breeds, presumptive 38 days of gestation to term). A panel of antisera was tested, including PGP 9.5 to describe the general intramural innervation, ChAT and TH to depict the cholinergic and nor-adrenergic components and NOS1, CGRP, SP, NPY, VIP, SOM, GAL, 5-HT to investigate the possible nitrergic, peptidergic and aminergic ones. A rich cholinergic innervation was present in adult bladder and urethra, along with a lesser number of adrenergic nerves and a small number of nitrergic ones. Either bladder or urethra received numerous CGRP-, SP-, NPY-, VIP-containing nerve fibres which were distributed throughout the muscle layers. All over the lower urinary tract strong to weak ChAT-, CGRP-, SP- and NPY-immunoreactivity was detected in intramural ganglia, in peripheral nerve bundles and around blood vessels. 5-HT-immunoreactive endocrine cells were present in the urethral epithelium. Early foetal organs were supplied only by cholinergic nerve fibres. Few NOS-, CGRP- and SP-ergic components appeared at the end of pregnancy. It can be guessed that sensory mediators such as CGRP and SP increase in postnatal ages while other neuropeptides, such as NPY and VIP, appear only after birth, as the urinary reflex consolidates.     

Intrinsic innervation of the ileocaecal junction in the horse: Preliminary study

Reason for performing study: In horses, morpho‐functional studies related to the enteric nervous system (ENS) controlling the sphincters are lacking. Objectives: To investigate immunohistochemically the morphology, distribution, density, phenotypes and projections of neurons controlling the ileocaecal junction (ICJ). Methods: Two young horses were anaesthetised and underwent midline laparotomy. The neuronal retrograde fluorescent tracer Fast Blue (FB) was injected into the wall of the ICJ. A post surgical survival time of 30 days was used. Following euthanasia, the ileum and a small portion of caecum were removed. Cryosections were used to investigate the immunoreactivity (IR) of the neurons innervating the ICJ for choline acetyltransferase (ChAT), neuronal nitric oxide synthase (nNOS), substance P (SP), calcitonin gene‐related peptide (CGRP) and neurofilament NF200kDa (NF). Results: Ileal FB‐labelled neurons innervating the ICJ were located in the myenteric plexus (MP) and submucosal plexus (SMP) up to 48 cm and 28 cm, respectively, from the point of the FB injections. Descending MP and SMP neurons were nitrergic (54 ± 11% and 68 ± 4%, respectively), cholinergic (60 ± 19% and 82 ± 11%, respectively), NF‐IR (54 ± 9% and 78 ± 21%, respectively), and SP‐IR (about 20% in both the plexuses). CGRP‐IR was expressed only by SMP descending neurons (45 ± 21%). In both the plexuses descending neurons coexpressing nNOS‐and ChAT‐IR were also observed (25 ± 11% and 61 ± 27%, respectively). Conclusions: The presence of ileal long projecting neurons innervating the ICJ suggests that they are critical for its modulation. Consequently, in bowel diseases in which the resection of the terminal jejunum and proximal ileum are required, it is preferable, whenever possible, to conserve the major portion of the ileum. Potential relevance: The knowledge of the phenotype of ENS neurons of the ileum might be helpful for developing pharmaceutical treatment of the ICJ motility disorders.     

Intrinsic Innervation of the Persian Squirrel (Sciurus anomalus) Ileum

Most investigations related to the characterisation of the enteric nervous system (ENS) are pivoted on the intestine of small rodents, but few studies are available on the ENS of wild or ‘unconventional’ rodents. Anti‐PGP 9.5 and anti‐Hu antibodies were utilised to recognise the distribution pattern of neuronal cell bodies and fibres of the ileum of the Persian squirrel (Sciurus anomalus) ENS. The percentages of subclasses of enteric neurones in the total neuronal population were investigated by neuronal nitric oxide synthase (nNOS), choline acetyltransferase (ChAT), calcitonin gene‐related peptide (CGRP), substance P (SP), and calbindin (CALB). Myenteric plexus (MP) and submucosal plexus (SMP) neurones showing nNOS immunoreactivity (IR) were 41 ± 4% and 11 ± 6%, respectively, whereas cells expressing ChAT‐IR were 56 ± 9% and 74 ± 16%, respectively. nNOS‐IR was co‐expressed by 21 ± 2% and 9 ± 4% of the MP and SMP cholinergic neurones, respectively, whereas the nNOS‐IR MP and SMP neurones co‐expressing ChAT‐IR were 86 ± 6% and 89 ± 2%, respectively. CGRP‐IR and SP‐IR were expressed, respectively, by 13 ± 5% and 6 ± 3% of MP and 18 ± 2% and 2 ± 2% of SMP neurones. CALB‐IR was expressed by 22 ± 8% and 56 ± 14% of MP and SMP neurones, respectively. MP and SMP cholinergic neurones co‐expressed nNOS‐IR (21 ± 2% and 9 ± 4%, respectively) and a very high percentage of nNOS‐IR neurones showed ChAT‐IR (86 ± 6% and 89 ± 2%, respectively). MP and SMP CALB‐IR neurones co‐expressed ChAT‐IR (100% and 63 ± 11%, respectively) and CGRP‐IR (89 ± 5% and 26 ± 7%, respectively). Our data might contribute to the neuroanatomical knowledge of the gastrointestinal tract in exotic mammals and provide a comparison with the available data on other mammals.     

Quantification and morphometry of myenteric neurones in the jejunum of Holtzman rats (Rattus norvegicus)

With 2 figures and 3 tables SUMMARY: The morphological pattern of the myenteric plexus (MP) is species-specific, and little is known about this pattern in Holtzman rats. The aim of the current experiment was the morphological and quantitative study of myenteric neurones in the Holtzman rat jejunum. Hematoxylin-Eosin and NADH-diaphorase (NADH-dp) staining were used to assess muscular layer thickness, neurone cell body area (CBA) and nuclei area (NA). Muscular layer thickness was found to be 114.77 ± 14.89 μm. Neuronal densities across the subregions of the jejunum were similar: mesenteric, 11.78 ± 2.89/mm(2) ; intermediate, 12.06 ± 2.69/mm(2) ; and antimesenteric, 10.67 ± 1.89/mm(2) . As expected, there was positive correlation between the CBA and NA of 79.19, 79.26 and 78.5% in the mesenteric, intermediate and antimesenteric subregions of the jejunum, respectively. Medium-sized neurones predominated in the ganglionic arrangement of the MP. These results indicate that the NADH-dp myenteric neurones in the jejunum of Holtzman rats are similar in many aspects to those found in the ileum of Holtzman rats and to those found in the small intestine of Wistar rats, including their location, ganglionic disposition and predominance of medium-sized CBA. However, neuronal density in the jejunum is lower than in the ileum. Based on these results showing morphological similarities to the MP of the Wistar rat, the Holtzman strain can be used to investigate the effects of adverse conditions on the morphology of the MP.     

Immunohistochemical characterization of neurons in the porcine ciliary ganglion

The present study was aimed at disclosing the chemical coding of nerve structures in the porcine ciliary ganglion (CG) using immunohistochemical methods. The substances under investigation included markers of "classical" neurotransmitters, choline acetyltransferase (ChAT), vesicular acetylcholine transporter (VAChT), tyrosine hydroxylase (TH) and dopamine beta-hydroxylase (DbetaH) as well as neuropeptides, somatostatin (SOM), galanin (GAL), substance P (SP), calcitonin gene-related peptide (CGRP), vasoactive intestinal polypeptide (VIP) and neuropeptide Y (NPY). Immunoreactivity to ChAT and VAChT was found virtually in all the neuronal somata and in numerous intraganglionic, varicose nerve fibres which often formed basket-like formations around the nerve cell bodies. Many CG neurons contained immunoreactivity for SOM (46%) or GAL (29%). Interestingly, a small number (approx. 1%) of the cholinergic somata stained for TH but not for DbetaH; nevertheless, some extra- and intraganglionic nerve fibres displayed immunoreactivity for DbetaH or TH. The CG perikarya stained neither for vasoactive intestinal polypeptide (VIP) nor for neuropeptide Y (NPY), but some NPY- or VIP-positive nerve terminals were observed within nerve bundles distributed outside the ganglion. SP- and CGRP-immunoreactivity was found in some intraganglionic nerve fibres only. The present study revealed that the porcine CG consists of cholinergic neurons many of which contain SOM and GAL. Thus, it can be assumed that in the pig, these neuropeptides are involved, complementary to acetylocholine, in the parasympathetic postganglionic nerve pathway to structures of the eye including the ciliary and iris sphincter muscles.     

Intrinsic innervation of the horse ileum

This paper describes the morphology and distribution of the enteric nervous system (ENS) cells and fibres immunoreactive for choline acetyltransferase (ChAT), neuronal nitric oxide synthase (nNOS), substance P (SP), calcitonin gene-related peptide (CGRP), NF200 kDa (NF200), and S100 protein. The percentages of subclasses of enteric neurons in the total neuronal population were investigated by the use of anti-PGP 9.5 or anti-NSE antibodies.ChAT-IR myenteric plexus (MP) and submucosal plexus (SMP) neurons were 66 ± 7% and 74 ± 15%, respectively, whereas those cells expressing nNOS-IR were 38 ± 7% and 5 ± 1%, respectively. MP and SMP neurons expressing both phenotypes were also present. SP-IR was expressed by 14 ± 13% of MP and 66 ± 8% of SMP neurons whereas CGRP-IR was observed only in the SMP (43 ± 6%). NF200-IR was expressed by 61 ± 15% and 91 ± 10% of the MP and SMP neurons, respectively. The majority of the CGRP-IR SMP neurons expressed also SP-IR. Almost all SP-IR neurons in both the plexuses were cholinergic. The present study quantifies the main neuronal subpopulations of the ENS of the horse ileum; these data might be utilized to understand the neuronal modifications which occur in several gastrointestinal tract disorders.