[Morphometric and histochemical characteristic of cluster organization of the neurons of rat spinal nerve sensory ganglion and of sympathetic trunk cervicothoracic ganglion].

The topographic pattern of neurons in spinal nerve sensory ganglion and of sympathetic trunk cervicothoracic ganglion was investigated at adult rats (n = 12). Results of the work have shown, that these organs are characterized by a heterogeneity of the neurons according to their morphometric (Nissl's stain) and histochemical (acetylcholinestherase and NADPH-diaphorase activity) parameters. The common feature of ganglia organization was demonstrated by the clustered pattern of neuron topography. Clusters were formed on a principle of heterogeneity, uniting from 3-4 to 9-10 neurons. The application of a combined histochemical method has allowed to identify the histo-functional charactristics of neurons within the clusters of the ganglia studied, which were also detected by standard histological methods.

Topographic regulation of phosphorylation in giant neurons of the squid, Loligo pealei: role of phosphatases.

In previous studies of phosphorylation in squid stellate ganglion neurons, we demonstrated that a specific multimeric phosphorylation complex characterized each cellular compartment. Although the endogenous protein profile of cell body extracts (giant fiber lobe, GFL), as determined by Coomassie staining, was similar to that of axoplasm from the giant axon, in this study we show that the protein phosphorylation profiles are qualitatively different. Whereas many axoplasm proteins were phosphorylated, including most cytoskeletal proteins, virtually all phosphorylation in perikarya was confined to low molecular weight compounds (<6 kDa). Because phosphorylation of exogenous substrates, histone and casein, was equally active in extracts from both compartments, failure to detect endogenous protein phosphorylation in cell bodies was attributed to the presence of more active phosphatases. To further explore the role of phosphatases in these neurons, we studied phosphorylation in the presence of serine/threonine and protein tyrosine phosphatase (PTP) inhibitors. We found that phosphorylation of axonal cytoskeletal proteins was modulated by okadaic acid-sensitive ser/thr phosphatases, whereas cell body phosphorylation was more sensitive to an inhibitor of protein tyrosine phosphatases, such as vanadate. Inhibition of PTPs by vanadate stimulated endogenous phosphorylation of GFL proteins, including cytoskeletal proteins. Protein tyrosine kinase activity was equally stimulated by vanadate in cell body and axonal whole homogenates and Triton X-100 free soluble extracts, but only the Triton X soluble fraction (membrane bound proteins) of the GFL exhibited significant activation in the presence of vanadate, suggesting higher PTP activities in this fraction than in the axon. The data are consistent with the hypothesis that neuronal protein phosphorylation in axons and cell bodies is modulated by different phosphatases associated with compartment-specific multimeric complexes.

Innervation of guinea-pig stellate ganglia by nitric oxide synthase, cocaine- and amphetamine-regulated transcript protein- and pituitary adenylate cyclase activating polypeptide-immunoreactive fibers.

The present study analyzed using immunohistochemical labeling the distribution and co-localization of nitric oxide synthase (NOS), cocaine- and amphetamine-regulated transcript peptide (CARTp) and pituitary adenylate cyclase activating polypeptide (PACAP) with choline acetyltransferase (ChAT)-immunoreactive fibers in the guinea-pig stellate ganglia. ChAT-immunoreactive fibers make pericellular baskets around virtually all stellate ganglia neurons. Pericellular baskets of NOS, CARTp and PACAP fibers were also present around numerous stellate ganglia neurons. Although all the NOS and PACAP fibers also exhibited ChAT immunoreactivity, only some of the CARTp fibers were ChAT-immunoreactive. No evidence of co-localization of NOS, PACAP and CARTp was obtained.These results indicate that NOS, PACAP and CARTp are present in distinct preganglionic axons innervating the guinea-pig stellate ganglia.

Role of the conserved WHXL motif in the C terminus of synaptotagmin in synaptic vesicle docking.

Synaptotagmin (Syt) I, an abundant synaptic vesicle protein, consists of one transmembrane region, two C2 domains, and a short C terminus. This protein is essential for both synaptic vesicle exocytosis and endocytosis via its C2 domains. Although the short C terminus is highly conserved among the Syt family and across species, little is known about the exact role of the conserved C terminus of Syt I. In this paper, we report a function of the Syt I C terminus in synaptic vesicle docking at the active zones. Presynaptic injection of a peptide corresponding to the C-terminal 21 amino acids of Syt I (named Syt-C) into the squid giant synapse blocked synaptic transmission without affecting the presynaptic action potential or the presynaptic Ca(2+) currents. The same procedure repeated with a mutant C-terminal peptide (Syt-CM) had no effect on synaptic transmission. Repetitive presynaptic stimulation with Syt-C produced a rapid decrease in the amplitude of the postsynaptic potentials as the synaptic block progressed, indicating that the peptide interferes with the docking step rather than the fusion step of synaptic vesicles. Electron microscopy of the synapses injected with the Syt-C peptide showed a marked decrease in the number of docked synaptic vesicles at the active zones, as compared with controls. These results indicate that Syt I is a multifunctional protein that is involved in at least three steps of synaptic vesicle cycle: docking, fusion, and reuptake of synaptic vesicles.

The perikaryal surface of spinal ganglion neurons: differences between domains in contact with satellite cells and in contact with the extracellular matrix.

The perikaryal surface of spinal ganglion neurons undergoes dynamic changes throughout life. In particular, numerous slender projections develop and retract continuously from this surface. We showed previously that the outgrowth of these projections, while an intrinsic property of spinal ganglion neurons, is also influenced by the surrounding microenvironment. Since the latter consists of satellite cells and the extracellular matrix, we sought to determine the relative contributions of each of these components to the outgrowth of perikaryal projections. To this end, we took advantage of a little known characteristic of the satellite cell sheaths: in the rabbit, these sheaths can exhibit gaps that leave the nerve cell body surface directly exposed to the extracellular matrix. We compared the surface domains covered by satellite cells with those in direct contact with the extracellular matrix. We found that the perikaryal projections are abundant in the former domains but are absent in the latter. We also found that the perineuronal extracellular matrix of rabbit spinal ganglia contains laminin and fibronectin, two glycoproteins that have been reported to promote the growth of axonal processes from sensory ganglion neurons. Laminin and fibronectin were also present at the level of the gaps in the satellite cell sheath. These results: (1) provide additional evidence that environmental factors influence the outgrowth of perikaryal projections from spinal ganglion neurons; (2) suggest that satellite cells permit the outgrowth of these projections; (3) suggest that in the spinal ganglia of adult rabbits the perineuronal extracellular matrix is not in itself able to promote the outgrowth of these projections. This study provides a further example of the influence that supporting neuroglial cells have on sensory ganglion neurons.

Morphological characteristics of primary sensory and post-synaptic sympathetic neurones supplying the temporomandibular joint in the cat.

The cells of origin of peripheral nerves that supply the temporomandibular joint were investigated by examining the centripetal transport of wheat germ agglutinin-horseradish peroxidase (WGA-HRP). Following WGA-HRP injection into the temporomandibular joint capsule of the cat, a large number of labelled neurones were observed in the trigeminal and superior cervical ganglia ipsilateral to the injection site, while no labelled neurones were detected in the cervical dorsal-root ganglia. Only one labelled neurone was seen in the stellate ganglion. Labelled neurones were primarily located in the posterolateral and dorsal regions of the trigeminal ganglion, but their distribution in the superior cervical ganglion was not localized to specific regions. The labelled neurones in the trigeminal ganglion were significantly larger than those in the superior cervical ganglion but the sizes of smaller neurones overlapped, suggesting that trigeminal ganglion neurones send both myelinated and unmyelinated fibres to the temporomandibular joint. The innervation of the temporomandibular joint by somatosensory and sympathetic fibres suggests that sympathetic nerves could be responsible for allodynia or neuropathic pain caused by temporomandibular disorders.

Arborization pattern of sympathetic preganglionic axons in the rat superior cervical and stellate ganglia.

Anterograde labeling technique with Phaseolus Vulgaris leucoagglutinin (PHA-L) was employed to observe how a single preganglionic axon arborizes in the superior cervical ganglion (SCG) and stellate ganglion (STG) of rats. PHA-L was injected into the intermediolateral nucleus of the spinal cord at the middle point between segments T1 and T2, and labeled axons were detected immunohistochemically in serial sections. We traced and drew three preganglionic axons over their full length in the SCG and STG. In SCG, the labeled axons bifurcated repeatedly and extended to a length of 600-700 microns in the rostrocaudal direction, and about 200 microns in the transverse direction. These three preganglionic axons made 11, 14 and 11 dense terminal plexus regions along their trajectory. The pattern of the most dense terminal plexus corresponded to the pericellular type dendritic plexus, one of the plexus patterns of dendritic collaterals of SCG neurons. In the STG, the extent of axonal arborization was more variable than that in the SCG, ranging from 400 to 800 microns in the rostrocaudal direction and about 400 microns in the transverse direction. The three analyzed axons made 21, 19 and 20 dense terminal plexus regions along their trajectory, with a similar pattern to those in SCG. These results indicated that there might be a columnar or ellipsoidal organization of postganglionic neurons which are innervated by single preganglionic axons.

[Ultrastructure of the sympathetic ganglia in hypoxia]. / Ul'trastruktura simpaticheskikh gangliev pri gipoksii.

Short-term hypoxia produces ultrastructural alterations in ganglions of rats in the form of dilatation of some membrane neuron compartments and sinuous plasmatic membrane. More long-term hypoxia produces structural changes of membrane cell components. An increase of lysosome number and lipofuscin granules alternations in chronic hypoxia (1 year) are similar to the age changes and are characterized by intensive accumulation of lipofuscin and Nissl bodies hypertrophy.

Preganglionic fibres of the adrenal medulla and cervical sympathetic ganglia: differential involvement during experimental American trypanosomiasis in rats.

The acute phase of experimental Chagas' disease in rats is associated with early lesions of the post-ganglionic sympathetic nerve terminals of the heart, the varicosities being the target. In the superior cervical and stellate ganglia the preganglionic fibres showed no signs of lesion in the course of experimental Chagas' disease. In the adrenal medulla, however, the acute phase of the Trypanosoma cruzi infection induced a clear rarefaction of the acetylcholinesterase-positive nerve fibres (20 and 32 days after infection). Recovery of the normal pattern occurred in most animals by day 125 after infection. At days 20, 32 and 46 after infection, electron-microscopic studies demonstrated the occurrence of damage in cholinergic nerve terminals contacting the chromaffin cells. The signs of damage included dense bodies, clumps of synaptic vesicles and filaments, rarefaction of all organelles, vacuoles and irregular contour. The ultrastructural peculiarities of the sympathetic ganglia may explain the ganglionar microenvironment protective against the hazardous factors elicited by acute Chagas' disease.

[The structure of the stellate sympathetic ganglia under long-term hypoxia]. / Stroenie zvezdchatykh simpaticheskikh gangliev v usloviiakh dlitel'noi gipoksii.

Changes of mitochondrial ultrastructure indicating not only degenerative processes but also the presence of organelle adaptive reactions were demonstrated in sympathetic neurons. Appearance of osmiophilic inclusions in mitochondrial matrix relates to most typical organelle alterations in ageing. Number of smooth endoplasmic reticulum vesicles equal in size to synaptic vesicles of nerve cells processes grows higher. Such vesicles are usually located near postsynaptic active zones and areas with neuronal plasmolemma free from glia. Their outward resemblance does not allow to claim that neuromediators and neuromodulators may turn up in these vesicles, although dendrites contain and may release certain biologically active substances. Basic difference between 24 and 30-months old rats lies in earlier degenerations of nerve cells in old animals. Forming of dark granules may be also associated with conditions of fixation. Small granular (SG) cells lacked typical lipofuscine granules, while their ultrastructure changed insignificantly. SG cells capacity to divide mitotically in functional maturity is likely to be one of the possible explanations of such difference.

Evidence that sympathetic preganglionic neurones are arranged in target-specific columns in the thoracic spinal cord of the rat.

It is recognised that selective activation of different target-specific sympathetic preganglionic neurones forms the basis of many autonomic responses. The anatomical basis for this could be the spatial arrangement of these neurones in the spinal cord nuclei. The present study tested this possibility in the rat by determining the location in single animals of three distinct groups of sympathetic preganglionic neurones, one group projecting to the superior cervical ganglion, another to the stellate ganglion and one to the adrenal medulla. Sympathetic preganglionic neurones to each of these targets were simultaneously labeled with fluorescent dyes, either Fluorogold, Fast Blue, or Diamidino Yellow. The numbers and general morphology of the neurones were similar to previous descriptions, and they were distributed in four subnuclei, the nucleus intermediolateralis pars principalis, the nucleus intermediolateralis pars funiculus, the nucleus intercalatus spinalis, and the nucleus intercalatus spinalis pars paraependymalis. It was shown that all three groups of neurones were represented in the more medial sympathetic nuclei, but in the nuclei at the lateral border of the intermediate grey matter each one of the three groups of neurones occupied a discrete location. Adrenal medullary sympathetic preganglionic neurones occupied a lateral aspect, the superior cervical ganglion sympathetic preganglionic neurones a medial aspect, and the stellate ganglion sympathetic preganglionic neurones a space between. Some sympathetic preganglionic neurones were double labeled after dye injections into the superior cervical and stellate ganglion thus indicating that they projected to both ganglia.(ABSTRACT TRUNCATED AT 250 WORDS)

Ultrastructural localization of neurotensin immunoreactivity in the stellate ganglion of the cat.

The morphological features and cellular relationships of neurotensin-containing axon terminals were studied at light and electron microscopic levels in the cat stellate ganglion using peroxidase and immunogold immunocytochemistry. By light microscopy, neurotensin immunoreactivity was detected within thin varicose fibres distributed throughout the ganglion. Immunoreactive fibres were no longer apparent following chronic deafferentation of the ganglion indicating that they were of extrinsic origin. Ultrastructural analysis of peroxidase immunostained material confirmed the presence of neurotensin immunoreactivity within a subpopulation of axonal varicosities which made synaptic contacts with the dendrites of ganglion cells. Within labelled varicosities neurotensin immunoreactivity was found by both immunoperoxidase and immunogold methods to be concentrated within large dense core vesicles 80-120 nm in diameter. These large dense core vesicles were characteristically distant from the active zone, in keeping with a possible extrasynaptic release of the peptide.

Immunohistochemical evidence for different pathways immunoreactive to substance P and calcitonin gene-related peptide (CGRP) in the guinea-pig stellate ganglion.

The colocalization of immunoreactivities to substance P and calcitonin gene-related peptide (CGRP) in nervous structures and their correlation with other peptidergic structures were studied in the stellate ganglion of the guinea pig by the application of double-labelling immunofluorescence. Three types of fibre were distinguished. (1) Substance P+/CGRP+ fibres, which sometimes displayed additional immunoreactivity for enkephalin, constituted a small fibre population of sensory origin, as deduced from retrograde labelling of substance P+/CGRP+ dorsal root ganglion cells. (2) Substance P+/CGRP- fibres were more frequent; some formed baskets around non-catecholaminergic perikarya that were immunoreactive to vasoactive intestinal polypeptide (VIP). (3) CGRP+/substance P- fibres were most frequent and were mainly distributed among tyrosine hydroxylase (TH)-immunoreactive cell bodies. The peptide content of fibre populations (2) and (3) did not correspond to that of sensory ganglion cells retrogradely labelled by tracer injection into the stellate ganglion. Therefore, these fibres are thought to arise from retrogradely labelled preganglionic sympathetic neurons of the spinal cord, in which transmitter levels may have been too low for immunohistochemical detection of substance P or CGRP. CGRP-immunoreactivity but no substance P-immunolabelling was observed in VIP-immunoreactive postganglionic neurons. Such cell bodies were TH-negative and were spared by substance P-immunolabelled fibre baskets. Retrograde tracing with Fast Blue indicated that the sweat glands in the glabrous skin of the forepaw were the targets of these neurons. The streptavidin-biotin-peroxidase method at the electron-microscope level demonstrated that immunoreactivity to substance P and CGRP was present in dense-cored vesicles of 50-130 nm diameter in varicosities of non-myelinated nerve fibres in the stellate ganglion. No statistically significant difference in size was observed between vesicles immunolabelled for substance P and CGRP. Immunoreactive varicosities formed axodendritic and axosomatic synaptic contacts, and unspecialized appositions to non-reactive neuronal dendrites, somata, and axon terminals. Many varicosities were partly exposed to the interstitial space. The findings provide evidence for different pathways utilizing substance P and/or CGRP in the guinea-pig stellate ganglion.

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.

Leporine dysautonomia: further evidence that hares suffer from grass sickness.

The recently described dysautonomia of hares has many similarities to equine grass sickness, particularly when the autonomic ganglia of affected hares and horses are compared by light microscopy. This study shows that the ultrastructural findings are also similar, with a loss of ribosomes from the rough endoplasmic reticulum and distension of its cisternae; the Golgi apparatus is not recognisable in affected neurons. Membranous stacks were identified in autonomic neurons of affected hares, a feature not characteristic of equine grass sickness but often found in feline dysautonomia. Staining with wheat germ agglutinin, a lectin recognising Golgi membranes, showed a lack of reactivity in affected neurons again suggesting a lack of a normal Golgi apparatus.

Hypertrophy of stellate ganglion cells in hypertensive, but not hyperactive, rats.

The dendritic complexity of peripheral autonomic neurons is positively matched with the size of the target they innervate, apparently by trophic interactions with the target (D. Purves, W. D. Snider, and J. T. Voyvodic. Nature Lond. 336: 123-128, 1988). We have asked whether the vascular hypertrophy associated with hypertension is accompanied by dendritic hypertrophy of sympathetic ganglion cells. To do this, we examined the morphology of stellate ganglion cells in the spontaneously hypertensive rat (SHR), its normotensive control Wistar-Kyoto rat (WKY), and two new strains derived from the SHR that independently express the hypertensive phenotype of the SHR (WKHT) and the behavioral hyperactivity present in the SHR (WKHA). Cells were examined by intracellular staining with horseradish peroxidase in in vitro preparations of the ganglia. Carotid arterial wall size was also examined. Significant hypertrophy of both the carotid arterial wall and stellate ganglion cell dendrites was observed in the two hypertensive strains (SHR and WKHT) but not in either of the normotensive strains (WKY and WKHA). This increased total dendritic length of stellate ganglion cells associated with hypertension provides a greater target area for preganglionic innervation that may result in hyperinnervation of these cells.

Endoscopic thoracic sympathectomy: evaluation of pulsatile laser, non-pulsatile laser, and radiofrequency-generated thermocoagulation.

We describe a modified technique for percutaneous denervation of the thoracic sympathetic chain by laser to treat selected cases of sympathetic causalgia of the upper extremities. The technique involves transpleural ablation with laser under thoracoscopic guidance through the second or third intercostal space-anterior axillary line. We also compare four different modalities of endoscopic denervation: A xenon chloride excimer laser (308 nm, 35 mJ/pulse, 20 pulses/sec, 2.2 mm catheter tip), CO2 laser (14 W, CW, 2 mm spot size), Nd:YAG laser (88 W, CW, 3 mm spot size), and radiofrequency-generated thermocoagulation (3 W, CW, 2.1 mm catheter tip) by performing bilateral thoracic sympathectomy on 12 mongrel dogs (three dogs each). Criteria analyzed included duration of exposure, power density, total energy output, laser penetration and spread, gross morphology, and scanning electron microscopy (SEM) of the destroyed neural tissue. Total ablation of the inferior segment of the stellate ganglion and the T1-T2 nerve roots by excimer laser required 83 +/1 1 Joules over an exposure period of 118 seconds. Ablation by CO2 and Nd:YAG laser required 153 +/- 13 Joules and 554 +/- 47 Joules delivered over 11 and 6 seconds respectively. In contrast, ablation of the same volume of nerve tissue by RF required 810 +/- 50 Joules over 270 seconds. SEM evaluation revealed that excimer and CO2 laser lesions were narrower in configuration compared to RF and Nd:YAG lesions which showed more lateral spread. The actual depth of penetration per 1 second exposure was similar for Excimer and CO2 (1.5 mm) and RF (1.3 mm), but deeper for Nd:YAG (3 mm).(ABSTRACT TRUNCATED AT 250 WORDS)

The epistellar body and what followed from its discovery.

The sequence of discoveries that has followed the investigation of this small yellow spot shows the value of studies begun out of "mere curiosity". The spot occurs on the stellate ganglion of octopods. It proved to be an enclosed sac, perhaps a gland. The search for it in squids and cuttlefishes led to the discovery of the giant nerve fibres. At first they were thought to be veins but we soon showed that they were nerve fibres concerned with jet propulsion. Their action potentials, membranes and synapses have been used for thousand of studies, including those that led to the Hodkin Huxley equations. They have been the basis of much of modern neuroscience. The epistellar body itself proved not to be a gland but a photoreceptor. Comparable photosensitive vesicles are especially large in the heads of deep-sea squids. In the mesopelagic ones they allow the squid to conceal itself by counterillumination, matching its own light output to the light coming from above. In bathypelagic squids the vesicles are enormous and probably keep the animals in the dark, where they breed. The function of the epistellar body, lying within the mantle of octopods is still unknown. It may act in the transparent larval stage to trigger the ejection of luminous plankton, which would be a hazard.

Neurotoxicological effects of trimethyltin on the stellate ganglion.

Hamsters treated with trimethyltin (TMT), 3 or 4 mg/kg IP, developed neurological symptoms, including tremor, within 24 hours. Postganglionic action potentials were recorded from isolated stellate ganglia of untreated hamsters (control ganglia) and TMT-treated hamsters (TMT ganglia). Compound action potentials (nicotinic transmission) of control and TMT ganglia were not significantly different. The afterdischarges induced by preganglionic stimulation at 30 Hz for 2 sec in the presence of 10(-3) M hexamethonium (muscarinic transmission) were significantly smaller in TMT ganglia than in control ganglia. The discharges induced by the muscarinic cholinoceptor agonist. McN-A-343, were also smaller in the TMT ganglia. Two other muscarinic processes, posttetanic potentiation and potentiation of the compound action potential by McN-A-343, were not significantly reduced in the TMT ganglia. Morphological studies of the ganglia revealed marked changes in the TMT ganglia with severe neuronal degeneration including vacuole formations and accumulations of lysosomes in the cytoplasm. These results demonstrate that TMT has marked anatomical effects on the stellate ganglion that may lead to the reduction in muscarinic cholinergic transmission.