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E Weihe

Publications and source records attributed to E Weihe.

At least 55 records · Page 3Linked to original sources
PubMed1996

Changes in pulmonary calcitonin gene-related peptide and protein gene product 9.5 innervation in rats infected with Mycoplasma pulmonis.

Changes in the expression of calcitonin gene-related peptide (CGRP) and polyneural protein gene product 9.5 (PGP) in hilar peribronchial innervation was investigated by immunohistochemistry in specific pathogen-free rats chronically infected with Mycoplasma pulmonis. Image analysis of immunostained sections revealed a reduction of approximately 62% in the amount of CGRP- and PGP-immunoreactive innervation of the peribronchial area in the infected animals. The portion of the total bronchial perimeter occupied by bronchus-associated lymphoid tissue was increased six-fold. The decrease in the CGRP-immunoreactive area could be the result either of an enhanced CGRP release or of a loss of nerve fibres. The decrease in the PGP-immunoreactive fibres indicates a degenerative loss of nerves. Increased bronchus-associated lymphoid tissue and decreased bronchial innervation by neurons releasing the immunomodulatory neuropeptide CGRP might both contribute to the pathophysiology and symptoms of mycoplasmosis in the rat.

Animals↗
PubMed1995

Calcitonin gene-related peptide and nitric oxide are involved in ultraviolet radiation-induced immunosuppression.

Contact hypersensitivity responsiveness to dinitrofluorobenzene is depressed in mice that are sensitized through skin sites exposed to ultraviolet (UV) radiation. Local impairment of contact hypersensitivity by UV has been associated with a reduction in antigen-presenting cell activity within UV-irradiated skin sites marked by a decrease in the density of Ia-positive epidermal Langerhans cells. Our recent studies have demonstrated that neurogenic mediators (e.g. calcitonin gene-related peptide (CGRP) and nitric oxide (NO) contribute to cutaneous inflammation following exposure of rats to high-dose UV radiation. Since CGRP and NO inhibit antigen presentation by dendritic cells in vitro, we have investigated the possible involvement of CGRP and NO in local immunosuppression in UV-irradiated rodents. Hindpaw skin of Sprague-Dawley rats and back skin of UV-susceptible C57BL/6 mice was exposed to acute UV radiation (2.0 J/cm2 and 0.5 J/cm2, respectively). Alterations in cutaneous CGRP content were analyzed by a specific radioimmunoassay (RIA). In separate experiments, the CGRP receptor antagonist CGRP-(8-37) (10-5 M) and the nitric oxide synthase inhibitor NG-nitro-L-arginine methyl ester (L-NAME) (2 X 10-5 M) were topically applied to UV-exposed skin before induction of contact hypersensitivity with dinitrofluorobenzene. Finally, we examined the effects of UV irradiation and epicutaneous application of CGRP on Ia-positive Langerhans cells by immunohistochemical analysis of epidermal sheets. It was found that UV exposure lead to a decrease in skin CGRP levels starting already 2 h after irradiation and reaching a minimum (less than 40% of non-irradiated control skin) at 6-12 h. Contact hypersensitivity reactions were significantly suppressed by UV radiation in rat skin (by 51%) and murine skin (by 80%). Topical administration of both CGRP-(8-37) and L-NAME before sensitization restored the capacity to respond to haptens applied to UV-exposed skin. Both UV exposure and topical CGRP reduced the density of Ia-positive epidermal cells. Our data indicate that CGRP may be released from sensory neurons following cutaneous UV irradiation and that CGRP and NO contribute of UV-induced local immunosuppression. Moreover, topical administration of CGRP or its antagonist may be able to modulate epidermal Langerhans cell activity in vivo.

Animals↗
PubMed1995

Follicular dendritic cells, interdigitating cells, and cells of the monocyte-macrophage lineage are the C1q-producing sources in the spleen. Identification of specific cell types by in situ hybridization and immunohistochemical analysis.

In a mouse model, we have shown previously that macrophages are the principal source of complement C1q. Furthermore, spleen, heart, and brain were found to contain substantial levels of murine C1q-specific mRNA, whereas liver, kidney, lung, and small intestine contained only trace amounts of C1q-specific mRNA. This work addresses the identification of C1q-expressing spleen cells in the rat, using Northern blotting and in situ detection of rat C1q mRNA combined with immunohistochemical analysis. The complete sequence of mRNA encoding the B chain of rat C1q was established. The cloned cDNA was found to hybridize primarily with spleen-derived mRNA of 1.2 kb, and additionally with a novel mRNA species of 3 kb. In situ hybridization together with immunohistochemistry revealed most of the C1q-expressing cells to be located in the red pulp of the spleen, and to be mainly of the monocyte-macrophage lineage, as indicated by coexpression of ED-1, an established marker for this type of cell. In addition, C1q was expressed in S-100-positive but ED-1-negative cells, in germinal center follicular dendritic cells, and in some interdigitating dendritic cells of the periarteriolar lymphatic sheath (PALS). These results indicate that the spleen, containing the above APCs that are all involved to a major extent in the adaptive immune response and are all capable of synthesizing C1q that is involved intimately in the innate immune response, may provide the site at which the innate and adaptive immune systems merge.

Amino Acid Sequence↗
PubMed1995

Coexpression of vasoactive intestinal peptide, calcitonin gene-related peptide and substance P immunoreactivity in parasympathetic neurons of the rhesus monkey lung.

By the use of light microscopic immunohistochemistry, the present study investigates whether substance P (SP) and calcitonin gene-related peptide (CGRP), which are well documented neurotransmitter candidates in primary sensory fibers, are also expressed in parasympathetic neurons of the rhesus monkey lung. A combination of double fluorescence immunohistochemistry and staining of adjacent sections revealed triple coexistence of SP, CGRP and the cholinergic co-transmitter vasoactive intestinal peptide (VIP) in a large number of neuronal cell bodies in intrinsic peribronchial ganglia. In addition, there was co-localization of SP and CGRP in choline acetyl-transferase (ChAT)-positive neurons. These data suggest that SP and CGRP, in addition to their sensory role, are cholinergic cotransmitter candidates in the postganglionic parasympathetic innervation of primate lung. Co-release and co-function of SP and CGRP with VIP and acetylcholine may be important in the regulation of pulmonary physiology and in pulmonary pathophysiology.

Animals↗
PubMed1995

Pro-enkephalin opioid peptides are abundant in porcine and bovine splenic nerves, but absent from nerves of rat, mouse, hamster, and guinea-pig spleen.

The opioidergic innervation of the mammalian spleen and possible species differences were investigated. Light-microscopic immunohistochemistry revealed that splenic nerves of bovine and porcine spleen, but not of rat, mouse, hamster and guinea-pig spleen contained proenkephalin-derived opioidergic innervation. Immunoreactivity to both prodynorphin and pro-opiomelanocortin was absent from splenic nerves. In bovine and porcine spleen, fibers immunoreactive for met-enkephalin, met-enkephalin-Arg-Phe, met-enkephalin-Arg-Gly-Leu, leu-enkephalin and peptide F formed perivascular plexus, traveled in trabecular connective tissue, and extended into the capsule. Spatial relationships with immune cells were apparent in the white and red pulp, excluding lymphoid follicles. Colocalization of enkephalin immunoreactivity with immunoreactivities for tyrosin hydroxylase, dopamin-beta-hydroxylase, and neuropeptide Y, but not for substance P or calcitonin gene-related peptide were found. Our results provide evidence that opioid expression in splenic innervation is strongly species-dependent and exclusively proenkephalin-derived. Colocalization with marker enzymes of noradrenergic neurons indicates a mainly postganglionic sympathetic origin of proenkephalinergic splenic innervation. Opioidergic perivascular nerves probably control the splenic blood flow. A close interrelationship of opioidergic fibers with immune cells provides the anatomical basis for direct effects of neurally released opioids on splenic immune functions.

Animals↗
PubMed1995

The distinct gene expression of the pro-hormone convertases in the rat heart suggests potential substrates.

The present study examined the distribution of the pro-hormone convertases PC1, PC2, furin, PACE4 and PC5 in the rat heart. Northern blot analysis of RNA extracted from cardiac tissues showed high levels of furin and PACE4 mRNA in the atria and ventricles, while PC5 mRNA was found to be expressed at high levels in the dorsal aorta. Although undetectable by Northern blot analysis, both PC1 and PC2 mRNA were detected by in situ hybridization and immunohistochemistry in discrete regions of the intracardiac para-aortic ganglia. In situ hybridization studies also showed that furin mRNA was observed in all cardiac tissues and cells, consistent with the previously reported ubiquitous expression of this gene. PACE4 mRNA was highly abundant in both the atria and ventricular cardiomyocytes, with low to undetectable levels observed in blood vessels. Finally, PC5 transcripts were expressed in the endothelial cells lining coronary vessels and the valve leaflets of the heart. The present localization studies in the heart and cardiac blood vessels suggests potential roles for each convertase in the processing of various neuropeptides, hormones and growth factors.

Amino Acid Sequence↗
PubMed1995

Changes of protein gene product 9.5 (PGP 9.5) immunoreactive nerves in inflamed appendix.

The existence of chronic appendicitis is controversial. In this prospective study, we investigated possible changes in the innervation of the appendix under different pathological conditions and correlated histological findings with clinical observation. Thirty appendectomy specimens and 14 appendices obtained from organ donors or patients who underwent right hemicolectomy were immediately fixed in Bouin's solution and processed for immunocytochemistry using an antiserum directed against the panneuronal marker protein gene product 9.5 (PGP 9.5). The density of PGP 9.5 immunostaining was evaluated by digitized morphometry. Significant differences in the density of the PGP 9.5-immunoreactive area were detected in the mucosal layer. In the nonacute appendicitis group, PGP 9.5 was increased (10.99 +/- 3.15%) as compared to acute appendicitis (3.89 +/- 1.77%) and controls (4.98 +/- 1.25%). The significant increase of PGP 9.5 in nonacute appendicitis may suggest axonal sprouting leading to hyperinnervation of the mucosa. This may be a neuronal factor in the pathophysiology of the disease and pain symptoms.

Abdominal Pain↗
PubMed1995

Human and monkey cholinergic neurons visualized in paraffin-embedded tissues by immunoreactivity for VAChT, the vesicular acetylcholine transporter.

The predicted C-terminal dodecapeptide of the human vesicular acetylcholine transporter (VAChT), deduced from the unique open reading frame of the recently cloned human VAChT cDNA, was conjugated through an N-terminal cysteine to keyhole limpet hemocyanin and used as an immunogen to generate polyclonal antihuman VAChT antibodies in rabbits. The distribution of the VAChT antigen in representative regions of the cholinergic nervous system was examined and compared to that of the acetylcholine biosynthetic enzyme choline acetyltransferase (ChAT), a specific marker for cholinergic neurons. VAChT immunoreactivity was localized in cell bodies of neurons in the basal forebrain and ventral horn of the spinal cord, regions in which major cholinergic projection systems to the cerebral cortex and to skeletal muscle, respectively, originate. The primate caudate nucleus contained numerous VAChT-positive interneurons. VAChT immunoreactivity was visualized in both cell bodies and extensive terminals in striatal interneurons, in contrast to formalin-fixed, deparaffinized sections stained for ChAT, in which cell bodies and fibers were stained but nerve terminals were less well visualized than with the VAChT antiserum. VAChT-positive nerve fibers were visualized in routinely immersion-fixed, paraffin-embedded human cerebral cortex, comparable to the density of fibers observed in perfusion-fixed Bouin's-postfixed monkey cerebral cortex. Extensive investment of virtually all principal ganglion cells of thoracic sympathetic ganglia of monkey and human with VAChT-positive nerve terminals was observed. VAChT-positive cell bodies, presumably corresponding to cholinergic sympathetic sudomotor neurons, were a significant fraction of the total principal cell population in monkey and human thoracic sympathetic ganglia.

Acetylcholine↗
PubMed1995

Reserpine- and tetrabenazine-sensitive transport of (3)H-histamine by the neuronal isoform of the vesicular monoamine transporter.

The transport of (3)H-histamine by the endocrine-specific (VMAT1) and neuronal (VMAT2) isoforms of the vesicular monoamine transporter has been evaluated in digitonin-permeabilized fibroblasts transfected with either VMAT1 or VMAT2. Transport of (3)H-histamine by both VMAT1 and VMAT2 was reserpine-sensitive but only transport by VMAT2 was inhibited by tetrabenazine. Maximal equilibrated levels of (3)H-histamine accumulation by VMAT2 (K(m) 300 mu M) were approximately three times greater than that mediated by VMAT1 when using a subsaturating concentration of exogenous (3)H-histamine (50 mu M). The expression of VMAT2 in histaminergic neurons in the rat brain was examined with polyclonal antipeptide antibodies specific for VMAT1 or VMAT2. VMAT2-positive and tyrosine hydroxylase-negative immunoreactive cell bodies were localized to the ventral part of the posterior hypothalamus in the region of the mamillary nuclei. The transport properties of VMAT2 and the distribution of VMAT2 in cell bodies in the tuberomammillary nucleus of the posterior hypothalamus reported here and the apparent absence of VMAT1 and VMAT2 in tissue mast cells support previous findings of reserpine-sensitive and reserpine-resistant pools of histamine in brain and peripheral tissues.

Adrenergic Uptake Inhibitors↗
PubMed1995

Expression of C1q, a subcomponent of the rat complement system, is dramatically enhanced in brains of rats with either Borna disease or experimental allergic encephalomyelitis.

In situ hybridization, RT-PCR and Northern blot analysis as well immunohistochemistry were used to examine the expression of C1q, a subcomponent of the rat complement system, in brains of rats infected with Borna disease virus (BDV) and rats afflicted with experimental allergic encephalomyelitis (EAE) induced by the adoptive transfer of myelin basic protein specific T cells. C1q mRNA, which was not detected in normal brain, became clearly detectable using RT-PCR analysis by d14 post infection (p.i.) with BDV. Maximal levels of C1q mRNA were reached 21 days p.i. when inflammatory reactions in the brain were also at a peak. Similarly, C1q mRNA was elevated when the clinical symptoms of EAE became evident 5 days following cell transfer. C1q positive cells, as identified by immunohistology, were preferentially localized in grey and white matter of the hippocampus and basolateral cortex. The C1q positive cells resembled microglial cells in morphology. The correlation of C1q expression with the development of neurological disease as well as the dramatic increase of C1q within brain regions with inflammatory lesions suggest that local biosynthesis of C1q may play a role in the pathogenesis of Borna virus induced and autoimmune encephalomyelitis.

Animals↗
PubMed1995

Calcitonin gene related peptide gene expression in collagen-induced arthritis.

Changes in calcitonin gene related peptide (CGRP) gene expression in spinal motoneurons and dorsal root ganglia (DRG) of rats subjected to collagen II induced arthritis (CIA) were evaluated by semiquantitative in situ hybridization. The effects of systemic treatment with the corticosteroid budesonide on basal CGRP expression and on changes under inflammatory conditions were examined. CIA caused a significant increase in CGRP mRNA levels in DRG. Budesonide reduced the constitutive CGRP mRNA levels in DRG, compared with untreated control rats, and reversed the CIA-induced increase. In contrast, CIA caused a marked decrease of CGRP mRNA levels in motoneurons. Budesonide had no effect on constitutive CGRP mRNA levels in motoneurons and attenuated the decrease in CGRP mRNA levels in motoneurons of rats subjected to CIA. Thus, peripheral inflammation and systemic corticosteroids have differential effects on CGRP expression in sensory and motor neurons. This may be relevant for the pathophysiology and pharmacotherapy of chronic inflammatory pain and motor dysfunction in chronic arthritis.

Animals↗
PubMed1995

Effect of neurotropic virus infection on neuronal and inducible nitric oxide synthase activity in rat brain.

To elucidate the potential role of inducible nitric oxide synthase (iNOS) and neuronal constitutive nitric oxide synthase (cNOS) in the pathogenesis of virus-induced encephalopathy, the activities of both NOS isoforms were determined in the brains of rats infected with Borna disease virus (BDV) or rabies virus. iNOS activity strongly increased, whereas neuronal cNOS activity significantly decreased in a time-dependent manner after either BDV or rabies virus infection. Choline acetyltransferase activity in the brain remained unchanged during both virus infections, suggesting that the decrease in cNOS activity does not reflect a generalized neuronal loss. Immunohistochemistry and Northern blot analyses indicate that the decrease in neuronal cNOS activity is due to a decrease in cNOS protein and mRNA synthesis. These results suggest that both an excessive generation of NO by activated macrophages or microglia, as well as a decrease of NO production in neurons may contribute to the neuropathogenesis of neurotropic virus infections.

Animals↗
PubMed1994

Distribution and chemical phenotypes of neuroendocrine cells in the human anal canal.

The presence, morphology and distribution of anal neuroendocrine cells were investigated with a panel of antisera and antibodies for neural markers, biogenic amines, and neuropeptides by the sensitive streptavidin-biotin-peroxidase immunocytochemistry, and coexistence patterns of neurochemically characterized neuroendocrine cells were examined by double immunofluorescence cytochemistry. In the colorectal zone, endocrine-like cells were immunoreactive for chromogranin A (CGA), serotonin (5-HT), pancreastatin (PST), peptide tyrosine tyrosine (PYY), glucagon-like peptide-1 (GLP-1), and somatostatin (SOM). Coexistence patterns of endocrine-like cell phenotypes with CGA and GLP-1 were heterogeneous. In the anal transitional zone (ATZ), endocrine-like cells were immunoreactive for CGA, 5-HT and PST. Furthermore, six new phenotypes of endocrine-like cells were characterized by their immunoreactivity for PYY, GLP-1, protein gene product 9.5 (PGP), calcitonin gene-related peptide (CGRP), neurotensin (NT), and SOM. All endocrine-like cell types in the ATZ were immunoreactive for CGA. In the squamous zone and perianal skin, CGA-immunopositive Merkel cells were also immunoreactive for CGRP, PST, NT and PGP. Neuroendocrine cells in the anal canal exhibit epithelial zone-related diversities in their neurochemical phenotypes and coexistence patterns, which may indicate specific regulatory functions. In the epithelium of the ATZ, which is regarded as metaplastic, endocrine-like cells expressed phenotypes characteristic of the neuroendocrine cells of the colorectal zone and the squamous zones, indicating a possible metaplastic origin of these cells.

Adolescent↗
PubMed1994

Functional identification of a vesicular acetylcholine transporter and its expression from a "cholinergic" gene locus.

The vesicular acetylcholine transporter (VAChT) has been identified and characterized based on the acquisition of high affinity vesamicol binding and proton-dependent, vesamicol-sensitive acetylcholine accumulation by a fibroblast cell line transfected with a clone from a rat pheochromocytoma cDNA library encoding this protein. The distribution of VAChT mRNA coincides with that reported for choline acetyltransferase (ChAT), the enzyme required for acetylcholine biosynthesis, in the peripheral and central cholinergic nervous systems. A human VAChT cDNA was used to localize the VAChT gene to chromosome 10q11.2, which is also the location of the ChAT gene. The entire sequence of the human VAChT cDNA is contained uninterrupted within the first intron of the ChAT gene locus. Transcription of VAChT and ChAT mRNA from the same or contiguous promoters within a single regulatory locus provides a previously undescribed genetic mechanism for coordinate regulation of two proteins whose expression is required to establish a mammalian neuronal phenotype.

Acetylcholine↗
PubMed1994

Localization of kappa-opioid receptor mRNA in neuronal subpopulations of rat sensory ganglia and spinal cord.

A partial cDNA encoding a kappa-opioid receptor was isolated and used to generate specific 35S-labeled probes to investigate the gene expression of the kappa-opioid receptor in sensory, sympathetic and spinal neurons of the rat by in situ hybridization. A subpopulation of mainly small and medium-sized neurons within dorsal root and trigeminal ganglia expressed kappa-receptor mRNA, but no signal was detectable in the superior cervical ganglion. kappa-Receptor mRNA was distributed over neurons throughout the dorsal horn and in laminae VII/VIII. Highest concentrations of positive neurons were seen in laminae I/II, dorsal lamina X and in the lateral spinal nucleus. alpha-Motoneurons and glial cells were not labeled. This distribution of kappa-receptor mRNA indicates preferential functions of kappa-receptors in sensory signalling with particular importance to nociception.

Animals↗
PubMed1994

Differential expression of mRNA encoding interleukin-12 p35 and p40 subunits in situ.

Interleukin-12 (IL-12) is a heterodimeric cytokine that plays an important role in the regulation of the immune response. For biological activity the expression of both subunits of IL-12, p35 and p40, is required. Moreover, in the mouse the p40 chain of IL-12 specifically inhibits the effects of the IL-12 heterodimer. In the present study we have analyzed by in situ hybridization the expression of the p35 and p40 mRNA in the spleens of BALB/c and mutant (SCID, nude, beige) mice, unstimulated and after in vivo stimulation with lipopolysaccharide (LPS) and with staphylococcal enterotoxin B (SEB). In unstimulated spleens of BALB/c mice p35 and p40 mRNA were only detectable in a few strongly stained single cells, p35 mRNA was expressed in addition weakly in the B cell areas. After injection of LPS or SEB, p40 mRNA was strongly induced in the T cell areas all over the spleen, whereas expression of p35 mRNA and its distribution pattern did not change. Surprisingly, most of the mRNA for p35 and p40 was localized in different areas of the spleen and was apparently produced by different cells. In macrophage-depleted spleens the increased expression of p40 mRNA in response to LPS was reduced but still detectable, demonstrating that other cells besides macrophages can up-regulate IL-12 p40 mRNA. Nude mice showed a stronger expression of p35 mRNA, SCID mice lacked the weak p35 staining of the B cell areas but showed a strong basal expression of both p35 and p40 mRNA and a focal response to LPS. The pattern of IL-12 mRNA expression in beige mice was the same as in normal mice. These data demonstrate a spatial dissociation of expression of the two chains of IL-12 and are compatible with a regulatory role of the isolated IL-12 p40 chain in vivo. In addition, they indicate that the demonstration of mRNA for both chains of IL-12 in whole tissues or cell mixtures is not necessarily indicative of functional IL-12.

Animals↗
PubMed1994

Distribution of the vesicular acetylcholine transporter (VAChT) in the central and peripheral nervous systems of the rat.

Expression of the acetylcholine biosynthetic enzyme choline acetyltransferase (ChAT), the vesicular acetylcholine transporter (VAChT), and the high-affinity plasma membrane choline transporter uniquely defines the cholinergic phenotype in the mammalian central (CNS) and peripheral (PNS) nervous systems. The distribution of cells expressing the messenger RNA encoding the recently cloned VAChT in the rat CNS and PNS is described here. The pattern of expression of VAChT mRNA is consistent with anatomical, pharmacological, and histochemical information on the distribution of functional cholinergic neurons in the brain and peripheral tissues of the rat. VAChT mRNA-containing cells are present in brain areas, including neocortex and hypothalamus, in which the existence of cholinergic neurons has been the subject of debate. The demonstration that VAChT is a completely adequate marker for cholinergic neurons should allow the systematic delineation of cholinergic synapses in the rat nervous system when antibodies directed to this protein are available.

Animals↗