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W Kummer

Publications and source records attributed to W Kummer.

At least 91 records · Page 5Linked to original sources
PubMed1993

Neuronal projections to the guinea pig stellate ganglion investigated by retrograde tracing.

Previous electrophysiological studies have revealed a peripheral sensory input to the stellate ganglion which does not originate from the dorsal root ganglia. The present retrograde tracing study aimed at evaluating whether the parent cell bodies are located in the periphery, i.e. in mediastinal ganglia. Following injection of Fast blue or wheat germ agglutinin-horseradish peroxidase into the right stellate ganglion of the guinea pig, retrogradely labelled cell bodies were observed in the intermediolateral and intercalated nuclei of the spinal cord as well as in dorsal root ganglia at segmental levels C8 to T6. In another case, the stellate ganglion was resected and replaced by a sponge soaked with 10 microliters of Fast blue. Labelling of preganglionic and sensory neurons parallelled that obtained by tracer injections. In neither case, however, were retrogradely labelled neurons found within or around the thoracic viscera (thymus, trachea, bronchi, esophagus, heart, great vessels of upper mediastinum) when these were cut serially en bloc. Controls performed by injection of Fast blue into the inferior mesenteric ganglion and investigation of the distal colon showed that our experimental protocol was able to visualize a peripheral projection towards a sympathetic ganglion--in this case from myenteric ganglia to the inferior mesenteric ganglion. We conclude that, in contrast to the circuitry connecting prevertebral sympathetic ganglia with the gut, the neuronal cell bodies providing peripheral sensory input from thoracic viscera to the right stellate ganglion most likely are not located within the mediastinal ganglia. Instead, they may reside within the stellate ganglion itself.

Amidines↗
PubMed1993

Ultrastructural connectivity of [leu]5-enkephalin-immunoreactive synapses in the guinea-pig stellate ganglion: involvement of spines and triads.

The ultrastructure of [leu]5-enkephalin-immunoreactive (ENK-IR) nerve fibres in the guinea-pig stellate ganglion was studied by means of pre-embedding immunohistochemistry. ENK-immunoreactivity was primarily contained within large dense core vesicles (91 +/- 21 nm in diameter; n = 259) but was absent from small clear vesicles (47 +/- 9 nm; n = 488) within the same nerve terminal that were concentrated at presynaptic regions. Thus, fast synaptic transmission mediated by ENK-IR terminals most probably does not involve [leu]5-enkephalin which may be released parasynaptically. Evaluating a total number of 123 synapses involving an ENK-IR presynaptic nerve ending, 47% terminated upon a spine, 46% upon a dendritic shaft, and 7% directly addressed a soma of a postganglionic neuron. In 30% of axo-dendritic synapses and 33% of axo-somatic synapses, non-immunoreactive dendrites or somata being postsynaptic to an ENK-IR terminal were in direct but non-synaptic contact to another dendrite/soma. Such arrangements are termed "triads". In view of the current hypotheses concerning the function of spines and triads, these findings indicate that ENK-IR terminals within the guinea-pig stellate ganglion may be involved in the generation of long-lasting synaptic events and modulation of non-synaptic intraganglionic communication.

Animals↗
PubMed1993

[Nerve supply to the anterior cruciate ligament and cruciate ligament allograft].

To confirm the innervation of the anterior cruciate ligament and anterior cruciate allograft the anterior cruciate ligament was grafted allogenic and deep-freeze preserved, in 12 white New Zealand rabbits. After removal from the donor animal the ligaments and pertaining bone tissue were placed in deep freeze at -90 degrees C for 72 hours. The grafts were fixed in the receiving animal by means of transosseous wire sutures. The non-operated contralateral anterior cruciate ligament served as control. Follow-up examinations were performed after 3, 6, 12, 24, 36 and 52 weeks. Immunohistochemical methods were employed to examine newly ingrown nerve fibres. Monoclonal antibodies against neurofilaments (to identify rapid conducting mechanoreceptive afferent A fibres) were used, as well as substance P (to identify slow conducting nociceptive afferent C fibres) and thyrosine hydroxylase (for the identification of vasomotor efferent C fibres). In the control ligaments we found an abundant amount of nerve fibres of all three kinds, each of these having its own typical distribution pattern. The fibres were mainly subsynovial, in some cases however also localised in the interfascicular connective tissue septae. At specialised end organs we could only identify Ruffini's corpuscles. No nerve fibres were found in the cruciate ligament allografts after 3 weeks, but an initial few fibres showed up after 6 weeks. After 12 weeks individual nerve fibres of all 3 kinds became noticeable, and after 24 weeks all three kinds of fibres were abundantly represented. No specialised end organs were found in the allografts.(ABSTRACT TRUNCATED AT 250 WORDS)

Afferent Pathways↗
PubMed1993

Long-lasting expression of JUN and KROX transcription factors and nitric oxide synthase in intrinsic neurons of the rat brain following axotomy.

In adult rats, the medial forebrain bundle (MFB) and mammillothalamic tract (MT) were unilaterally transected, resulting in axotomy of neurons in numerous areas such as the substantia nigra (SN), ventral tegmental area (VTA), nucleus (ncl.) mammillaris (MnM), and ncl. parafascicularis of the thalamus (PF). In these areas, expression of the transcription factor proteins c-JUN, JUN B, JUN D, c-FOS, FOS B, KROX-20, KROX-24, and CREB was investigated by immunocytochemistry up to 150 d. In parallel, the expression of nitric oxide synthase (NOS) was investigated both immunocytochemically and by the NADPH-diaphorase reaction (NDP), and the antibody against NOS was further characterized. The colocalization of c-JUN with NDP or NOS was also studied in the axotomized neurons. c-JUN and JUN D became visible in nuclei of many neurons of the ipsilateral MnM, PF, VTA, and SN (predominantly in the pars compacta and those double labeled by tyrosine hydroxylase, TH) after 36 hr, not after 24 hr, following transection of MFB and MT. In MnM, c-JUN and JUN D persisted at a nearly maximal level for up to 150 d. In PF, these proteins returned to control levels after 75 d. Expression of c-JUN and JUN D declined in the VTA after 30 d, but in the SN, it already declined after only 10 d. KROX-24 had a later onset of expression, being visible after 3 d in all investigated areas, and its pattern was similar to that of JUN proteins, although labeling was visible in fewer nuclei and declined earlier. JUN B, c-FOS, FOS B, and KROX-20 were not expressed in these areas, and substantial alterations of CREB immunoreactivity (CREB-IR) could not be detected. A subset of SN neurons (predominantly in the pars reticularis and negative for TH) presented an early and transient expression of all studied JUN, FOS, and KROX-24 proteins within 3 hr of transection that declined between 24 hr and 48 hr to basal levels. This expression pattern is typical of that caused by transynaptic stimulation (probably due to excitation of descending striatal neurons running within the MFB) and was clearly distinct from that evoked by c-JUN, JUN D, and KROX-24 IRs after 36 hr (predominantly in the pars compacta). An ipsilateral increase in NOS and NDP became visible in many neurons of the MnM after 10 d, but not after 5 d, and this persisted up to 150 d. The temporospatial pattern of NDP was similar to the pattern of NOS-IR.(ABSTRACT TRUNCATED AT 400 WORDS)

Amino Acid Oxidoreductases↗
PubMed1992

Ultrastructure of calcitonin gene-related peptide-immunoreactive nerve fibres in guinea-pig peribronchial ganglia.

Calcitonin gene-related peptide-immunoreactive (CGRP-IR) nerves within guinea-pig peribronchial ganglia were studied at ultrastructural level using pre-embedding immunohistochemistry. Preterminal CGRP-IR axons were unmyelinated and contained singular immunoreactive dense core vesicles. CGRP-IR axon terminals were filled with numerous non-reactive small clear vesicles and few immunoreactive dense core vesicles. Some of these terminals were presynaptic to large neuronal processes emerging from local ganglion cells. Another population of presynaptic varicosities lack CGRP-IR. Within CGRP-IR terminals, non-reactive clear vesicles were clustered at the presynaptic membrane whereas CGRP-IR large vesicles remained in some distance from the synaptic cleft. The present observations indicate that: (1) at least two neurochemically different types of synaptic input exist to guinea-pig peribronchial ganglia. (2) CGRP-IR presynaptic terminals probably utilize a non-peptide transmitter for fast synaptic transmission, whilst the peptides are likely to be released parasynaptically and may act in a modulatory fashion.

Animals↗
PubMed1992

Localization of vasoactive intestinal polypeptide-receptor-immunoreactivity in human salivary glands.

A monoclonal VIP-receptor antibody derived from a human adenocarcinoma cell line (HT 29) was used in combination with immunogold silver staining for the immunohistochemical demonstration of VIP-receptor (rec) immunoreactivity (IR) in paraffin-embedded human salivary glands (parotid, palatal, labial glands). VIP-rec-IR was localized to mucous endpieces of labial and--to a lesser extent--palatal glands, intercalated ducts of the parotid gland, and excretory ducts of all glands investigated. The findings correlate well with known effects of VIP on mucous release and electrolyte transport in salivary glands. Lack of VIP-rec-IR at serious acini may point to immunologically different receptor subtypes in these glands.

Antibodies, Monoclonal↗
PubMed1992

Chemoreceptor A-fibres in the human carotid body contain tyrosine hydroxylase and neurofilament immunoreactivity.

Previous retrograde tracing studies on rat and guinea-pig showed a projection of sensory tyrosine hydroxylase-immunoreactive neurons to the region of the carotid bifurcation via the carotid sinus nerve. In the present study, focussing on the sensory innervation of the human carotid body, antisera to tyrosine hydroxylase and other catecholamine synthesizing enzymes were applied for an immunohistochemical investigation of carotid bodies obtained at autopsy. In addition, an array of antisera directed to non-enzyme antigens known to be present in viscero-afferent neurons were incorporated in the study. The glomic lobules consisting of glomus cells and sustentacular cells contained a variable number of enzyme-immunoreactive glomus cells. Arteries were supplied by nerve fibres displaying the full phenotype of sympathetic noradrenergic axons, i.e. immunoreactivity to tyrosine hydroxylase, aromatic-L-amino-acid-decarboxylase and dopamine-beta-hydroxylase. The glomic lobules, however, were densely innervated by tyrosine hydroxylase-immunoreactive axons lacking immunoreactivity to aromatic-L-amino-acid-decarboxylase and dopamine-beta-hydroxylase. These fibres reacted with neurofilament 160kD-antibody but were devoid of immunoreactivity to all neuropeptides tested (calcitonin gene-related peptide, somatostatin, substance P). Ultrastructurally, tyrosine hydroxylase/neurofilament 160kD-immunoreactive axons gave rise to large axonal swellings filled with mitochondria and vesicles, and established extensive contacts to glomus cells. Nerve bundles surrounded by a perineural sheath contained both myelinated (2.0-2.8 microns in diameter) and unmyelinated (0.14-3.0 microns) tyrosine hydroxylase-immunoreactive axons. Most of the unmyelinated immunoreactive axons were running singularly within a Schwann cell-sheath. Judged from the pattern of immunoreactivities as well as their preterminal and terminal ultrastructure, tyrosine hydroxylase-immunoreactive axons innervating glomus cells are of sensory origin. Although final proof by retrograde tracing cannot be presented in man, this conclusion is supported by experimental evidence in laboratory animals. The myelinated immunoreactive axons correspond to chemoreceptor A-fibres whereas the classification of the large unmyelinated immunoreactive axons has yet to be established. The lack of immunoreactivity to the dopamine-synthesizing enzyme, aromatic-L-amino-acid-decarboxylase, in this fibre type does not support the view of dopamine being the primary transmitter of chemoreceptor afferents.

Aged↗
PubMed1992

The sensory and sympathetic innervation of guinea-pig lung and trachea as studied by retrograde neuronal tracing and double-labelling immunohistochemistry.

The sympathetic and sensory innervation of guinea-pig trachea and lung were studied by means of retrograde neuronal tracing using fluorescent dyes, and double-labelling immunofluorescence. Sympathetic neurons supplying the lung were located in stellate ganglia and in thoracic sympathetic chain ganglia T2-T4; those supplying the trachea resided in the superior cervical and stellate ganglia. Retrogradely labelled sympathetic neurons were usually immunoreactive to tyrosine hydroxylase; the majority also contained neuropeptide Y immunoreactivity. However, a small number were non-catecholaminergic (i.e. tyrosine hydroxylase negative), but neuropeptide Y immunoreactive. Within the airways, tyrosine hydroxylase/neuropeptide Y-immunoreactive axons were found in the smooth muscle layer, around blood vessels including the pulmonary artery and vein, and to a lesser extent in the lamina propria. Periarterial axons contained in addition dynorphin immunoreactivity. Sensory neurons supplying the lung were located in jugular and nodose vagal ganglia as well as in upper thoracic dorsal root ganglia; those supplying the trachea were most frequently found bilaterally in the nodose ganglia and less frequently in the jugular ganglia. A spinal origin of tracheal sensory fibres could not be consistently demonstrated. With regard to their immunoreactivity to peptides, three types of sensory neurons projecting to the airways could be distinguished: (i) substance P/dynorphin immunoreactive; (ii) substance P immunoreactive but dynorphin negative; and (iii) negative to all peptides tested. Substance P-immunoreactive neurons innervating the airways invariably contained immunoreactivity to neurokinin A and calcitonin gene-related peptide. Retrogradely labelled neurons located in the nodose ganglia belonged almost exclusively (greater than or equal to 99%) to the peptide-negative group, whereas the three neuron types each represented about one-third of retrogradely labelled neurons in jugular and dorsal root ganglia. Within the airways, axons immunoreactive to substance P/neurokinin A and substance P/calcitonin gene-related peptide were distributed within the respiratory epithelium of trachea and large bronchi, in the lamina propria and smooth muscle from the trachea down to the smallest bronchioli (highest density at the bronchial level), in the alveolar walls, around systemic and pulmonary blood vessels, and within airway ganglia. Those axons also containing dynorphin immunoreactivity were restricted to the lamina propria and smooth muscle. The origin of nerve fibres immunoreactive for vasoactive intestinal polypeptide, of which a part were also neuropeptide Y immunoreactive, could not be determined by retrograde tracing experiments. Vasoactive intestinal polypeptide-immunoreactive fibres terminating within airway ganglia may be of preganglionic parasympathetic origin, whereas others (e.g. those found in smooth muscle) may arise from intrinsic ganglia.(ABSTRACT TRUNCATED AT 400 WORDS)

Animals↗
PubMed1992

Neuronal specificity and plasticity in the autonomic nervous system.

The autonomic nervous system is divided into the sympathetic, parasympathetic and enteric subdivisions. The present review is focussed upon the highly specialized reflex organization and neurochemistry of sympathetic parasympathetic neurons. The currently available informations allow to conclude that autonomic control of each peripheral target tissue is specifically regulated under normal conditions but nevertheless able to respond to altered conditions by changes in neural activity and mediator expression.

Animals↗
PubMed1992

Expression of nitric oxide synthase in kidney macula densa cells.

The distribution of nitric oxide synthase (NOS), the enzyme by which NO is generated from L-arginine, was investigated in rat kidney. The indirect immunofluorescence technique using a polyclonal antibody against type I NOS was applied, followed by the histochemical NADPH diaphorase staining technique on the same sections in order to demonstrate the enzymatic activity of NOS. Macula densa cells were strongly stained by both techniques, demonstrating abundant NOS in the cytoplasm of these cells. In addition, these findings were confirmed by nonradioactive in situ hybridization, thus demonstrating the corresponding messenger RNA in macula densa cells as well. Our findings provide the morphological basis for a possible role of NO as a mediator substance in signal transfer from distal tubular fluid to glomerular arterioles.

Amino Acid Oxidoreductases↗
PubMed1992

Nitric oxide synthase in VIP-containing vasodilator nerve fibres in the guinea-pig.

We investigated the possibility of nitric oxide (NO), a powerful vasodilator agent, being synthesized by perivascular nerve fibres. Immunoreactivity and catalytic activity of the NO synthesizing enzyme, NO synthase (NOS), were demonstrated in perivascular nerve fibres of blood vessels receiving autonomic vasodilator innervation, but not of those innervated exclusively by vasoconstrictor nerve fibres. Double-labelling techniques allowed identification of NOS-containing nerve fibres as belonging to the vasoactive intestinal peptide (VIP)/acetylcholine-containing class whereas noradrenergic and substance P-containing perivascular fibres were devoid of NOS. We suggest that, in addition to its endothelial source, NO is a neuronal co-mediator of VIP/cholinergic vasodilation.

Amino Acid Oxidoreductases↗
PubMed1992

Nitric oxide synthase in cardiac nerve fibers and neurons of rat and guinea pig heart.

Participation of nitric oxide (NO) in the autonomic innervation of rat and guinea pig hearts was investigated by applying the NADPH diaphorase technique and immunohistochemistry with NO synthase antiserum. We present evidence that NO synthase is localized in cardiac ganglion cells and nerve fibers innervating the sinuatrial and atrioventricular nodes, the myocardium, local neurons, coronary arteries, and pulmonary vessels, suggesting an involvement of NO in neurogenic heart rate regulation, myocardial cell function, neuronal transmission in cardiac ganglia, and coronary as well as pulmonary vasodilation.

Amino Acid Oxidoreductases↗
PubMed1992

Immunohistochemical localization of receptors for vasoactive intestinal peptide and substance P in human trachea.

BACKGROUND: Tissue sections of human cervical trachea were processed for immunohistochemical demonstration of receptors for substance P [using an anti-SP anti-idiotypic antiserum directed toward the ligand binding site of the receptor (Couraud J-Y, Escher ED, Regoli D, Imhof V, Rossignol B, Pradelles P. Anti-substance P anti-idiotypic antibodies: Characterization and biological activities. J Biol Chem 1985;260:9461-9; Couraud J-Y, Maillet S, Grassi J, Frobert Y, Pradelles P. Characterization and properties of anti-substance P antiidiotypic antibodies. Methods Enzymol 1989; 178:275-300)] and vasoactive intestinal peptide (VIP; utilizing a monoclonal antibody toward VIP receptors of an adenocarcinoma cell line (Pichon J, Hirn M, Muller J-M, Mangeat P, Marvaldi J. Anticell surface monoclonal antibodies which antagonize the action of VIP in a human adenocarcinoma cell line (HT29). EMBO J 1983;2:1017-22)], respectively. Mucus cells of the submucosal glands (identified by periodic acid Schiff staining) and neuroendocrine cells of the respiratory epithelium (identified by immunoreactivity to protein gene product 9.5) displayed intense VIP receptor-immunoreactivity. Other tissue components known to respond to exogenously administered VIP, e.g., trachealis muscle, lacked VIP receptor-immunoreactivity, indicating that the monoclonal antibody did not label all receptor subtypes. In accordance with the known pharmacological actions of substance P upon the airways, the anti-substance P receptor antibody labeled the trachealis muscle, submucosal glands, and respiratory epithelium, predominantly at the luminal aspect. Since substance P as well as the structurally related tachykinin, neurokinin A, competed with the anti-receptor antibody in binding to the tissue section, it is likely that both NK-1 and NK-2 receptor subtypes were labeled. The present histochemical approach to localize peptide receptors in the trachea allowed precise analysis of distribution unreached by previous studies using autoradiography. Together with pharmacological data, these morphological findings contribute to the understanding of the sequences of events evoked by the neuropeptides, substance P and VIP, in the human trachea.

Antibodies, Monoclonal↗
PubMed1991

Different types of calcitonin gene-related peptide-immunoreactive neurons in the guinea-pig stellate ganglion as revealed by triple-labelling immunofluorescence.

A triple-labelling immunofluorescence technique was used to study the patterns of coexistence of calcitonin gene-related peptide (CGRP), neuropeptide Y (NPY), and tyrosine hydroxylase (TH) in the guinea-pig stellate ganglion. CGRP-immunoreactive postganglionic neurons, which all were of the non-catecholaminergic type, could be divided into NPY-positive and NPY-negative populations. Sweat glands, which are a known target of CGRP-immunoreactive sympathetic neurons, exhibited exclusively fibers of the CGRP+/NPY- phenotype. Lack of coexistence of CGRP- and NPY-immunoreactivity was also observed in nerves within skeletal muscle, brown adipose tissue and hairy skin. The findings document a previously unknown diversity of CGRP-immunoreactive postganglionic sympathetic neurons, and indicate the existence of an addition, presently unidentified target of non-catecholaminergic, CGRP-immunoreactive sympathetic neurons.

Adipose Tissue, Brown↗
PubMed1991

Substance P- and calcitonin gene-related peptide-like immunoreactivities in the human carotid body studied at light and electron microscopical level.

The distribution of substance P- (SP-) and calcitonin gene-related peptide-like immunoreactivities (CGRP-LI) was studied in the human carotid body at the light and electron microscopic level. Of the different compartments of the carotid body, the glomic lobules received the densest innervation by SP/CGRP double-labelled axons, followed by interlobular arteries and interlobular connective tissue. Ultrastructurally, preterminal SP/CGRP-LI axons are unmyelinated and measure 0.09-1.02 micron in diameter with a median diameter of 0.28 micron (calculated conduction velocity: 0.5 m/s). Within the glomic lobules, vesicle-containing varicosities are numerous around glomus cells, but only few of them directly contact (non-synaptically) glomus cells. The findings are consistent with the existence of two populations of SP/CGRP-LI C-fibers, one of them probably representing chemoreceptor C-fibers, the other belonging to the ubiquitous vascular sensory innervation. In addition to its localization in nerve fibers, CGRP-LI also occurs in dense core vesicles of a subpopulation of glomus cells. In this regard, the human carotid body is unique among mammalian species studied so far, which severely hampers the interpretation of pharmacological data obtained in laboratory animals in terms of human physiology.

Aged↗
PubMed1991

Neuropeptide Y mRNA regulation in rat sympathetic ganglia: effect of reserpine.

To study the mechanism underlying trans-synaptic neuropeptide regulation, mRNA levels of neuropeptide Y were examined in the rat stellate and superior cervical ganglia using a specific neuropeptide Y cRNA probe. Basal levels of neuropeptide Y mRNA were detectable in total RNA extracts from single ganglia. Reserpine induced a large rise in ganglion neuropeptide Y mRNA. Decentralization prevented the increase of neuropeptide Y mRNA content in the ganglia. This suggests that the reserpine induced increase in neuropeptide Y mRNA was dependent on transsynaptic stimulation. Consequently, neuropeptide mRNA levels in sympathetic ganglia may be under the control of preganglionic impulse flow.

Autonomic Fibers, Preganglionic↗
PubMed1991

Tissue distribution of neutral endopeptidase 24.11 ('enkephalinase') activity in guinea pig trachea.

The distribution of neutral endopeptidase 24.11 (NEP; 'enkephalinase') activity was studied on tissue sections of the guinea pig trachea using a histochemical method based on the catalytic activity of the enzyme. The specificity for NEP of the histochemical reaction was verified by application of an array of peptidase inhibitors. NEP activity was most prominent on the respiratory epithelium, but occurred also in submucous glands, connective tissue of the lamina propria, perichondrium and chondrocytes. The findings suggest that NEP in the trachea is involved in various functions, cleavage of neurally released peptides being only one of them.

Animals↗