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At least 19 recordsLinked to original sources
PubMed1989

Trigeminal fibre collaterals storing substance P and calcitonin gene-related peptide associate with ganglion cells containing choline acetyltransferase and vasoactive intestinal polypeptide in the sphenopalatine ganglion of the rat. An axon reflex modulating parasympathetic ganglionic activity?

In immunohistochemical studies on rat two types of nerve fibres, both showing substance P and calcitonin gene-related peptide-like immunoreactivity, have been localized in the sphenopalatine ganglion, the principal cells of which contain both vasoactive intestinal polypeptide and choline acetyltransferase. One fine-calibre fibre type forms basket-like arrangements around approximately 3-5% of the principal neurons, whereas another, more coarse type traverses the ganglion without making contacts with the ganglion cells. By transection of nerves connecting with the ganglion, in combination with retrograde tracing experiments, it was concluded that the fine-calibre fibres exclusively come from the trigeminal ganglion, whereas the second type in addition, and mainly, originate in the internal carotid ganglion which is situated along the greater superficial petrosal nerve and the pterygoid nerve at their junction with the internal carotid nerve. The brain vasculature was shown to be one target structure for the innervated principal cells in the sphenopalatine ganglion. The arrangement provides the functional possibility for a modulatory interaction between the autonomic and sensory systems, thus resembling an axon reflex mechanism in the peripheral nervous system.

Animals↗
PubMed1988

Quantitative cytology of ganglion neurons and satellite glial cells in the superior cervical ganglion of the sheep. Relationship with ganglion neuron size.

Neurons and glial cells of the superior cervical ganglion of sheep were investigated with morphometric methods in the light and electron microscope. The nerve cell sectional area (measured on nucleated cell profiles) ranged from 165 to 2500 microns2, which corresponds to range in cell diameter from 14 to 56 microns and a range in cell volume from 1600 to 93,000 microns3, i.e. a 60-fold volume difference between smallest and largest neurons. The distribution of cell sizes appeared unimodal, with a predominance of small neurons; there were no variations in different parts of the ganglion. This wide range in nerve cell sizes is discussed in the light of the suggestion that large neurons innervate a greater amount of target tissue (e.g. smooth muscle) and are less readily excitable than smaller neurons: it is thus possible that there is differential recruitment of ganglion neurons in autonomic reflexes. The ultrastructural features of ganglion neurons in the sheep were similar to those observed in small laboratory animals. The relative volumes of perikaryal cytoplasm occupied by mitochondria and Golgi apparatus were 8.5% and 4.8%, respectively, but the average values were the same in small and large neurons. Subsurface cisternae of endoplasmic reticulum were common in the perikaryon, while in the dendrites clusters of synaptic vesicles were found beneath the plasma membrane; the absence of a glial wrapping at the latter sites suggests that they are points of (non-synaptic) release of transmitters. The extent of the capsule that satellite cells form around each neurons was compared in size-based classes of neurons. There was no difference in the size of glial nuclei, and this suggests that glial cells are probably of uniform size. However, glial cells were more densely packed over the surface of large neurons than over the surface of small neurons--in fact the packing density was proportional to the ganglion neuron volume, rather than to its surface. The average thickness of the glial capsule was significantly greater around large than around small neurons. It is suggested that the matching of glial cell number and nerve cell volume is achieved during development by glial cell mitosis taking place long after the nerve cells have ceased dividing.

Animals↗
PubMed1996

[Influence of stellate ganglion block and electrical stimulation of the stellate ganglion on bilateral brachial arterial blood flow--is stellate ganglion block effective either unilaterally or bilaterally?].

The purpose of this study was to investigate the influence of the stellate ganglion block (SGB), stellate ganglion electrical stimulation (SGES) and stellate ganglionectomy on bilateral arterial blood flows (BAF). Sixteen mongrel dogs were divided into two groups; a SGB group (n = 8) and a SGES group (n = 8). Anesthesia was induced with pentobarbital 25 mg.kg-1 and the animals were mechanically ventilated to maintain proper PaO2 (90-100 mmHg) and PaCO2 (35-40 mmHg). After a thoracotomy, the SGB with 0.5% mepivacaine 1.0 ml was performed in the SGB group. SGES was performed at a strength of 12 volts, and at a frequency of 50 Hz, applied for 15 minutes and then 15 minutes after the SGES, stellate ganglionectomy was performed in SGES group. In the SGB group, BAF in the blocked side increased significantly but BAF in the contralateral side decreased significantly after SGB. In the SGES group, bilateral BAF decreased significantly (Lt > Rt) and after the stellate ganglionectomy, bilateral BAF increased more than after SGES. These results suggest that the SGB may not be effective on the contralateral side under normal conditions, but under the conditions of sympathetic stimulation, the SGB may be effective on the contralateral side.

Animals↗
PubMed1979

The effects of post-ganglionic axotomy on selective synaptic connexions in the superior cervical ganglion of the guinea-pig.

Stimulation of preganglionic axons arising from different levels of the thoracic spinal cord causes different effects on end-organs supplied by the superior cervical ganglion (Langley, 1892; Nja & Purves, 1977a; Lichtman, Purves & Yip, 1979). For example, stimulation of the first thoracic ventral root (T1) causes pupillary dilatation and widening of the palpebral fissure; stimulation of T4, on the other hand, has little effect on the eye, even though axons arising from this level innervate about as many superior cervical ganglion cells as those from T1. Thus ganglion cell innervation is selective. (1) Three months after crushing the major post-ganglionic branches of the superior cervical ganglion this differential effectiveness is lost: T1 and T4 stimulation have approximately equal effects on the end-organs of the eye. (2) In normal animals, the cellular counterpart of selective end-organ effects is the innervation of each ganglion cell by a contiguous subset of the spinal segments that innervate the ganglion as a whole. One of these segments is usually dominant, the strength of innervation from adjacent segments falling off as a function of distance from the dominant one (Nja & Purves, 1977a). Intracellular recordings from ganglion cells 3 months after post-ganglionic axotomy showed that this selective pattern is re-established. (3) Since the innervation of ganglion cells appears normal, the abnormal end-organ responses after post-ganglionic axotomy suggest that ganglion cell axons are not limited to their original targets during peripheral re-innervation. This suggestion is supported by the finding that ganglion cells sending axons to different peripheral destinations via the second and third cervical spinal nerves were no longer distinguishable on the basis of their segmented inputs 3 months after post-ganglionic axotomy. (4) Similar results were obtained when the preganglionic cervical trunk was cut at the same time as the post-ganglionic axons were crushed; the pattern of end-organ responses was abnormal, whereas individual ganglion cells were re-innervated according to the rules of contiguity and segmental dominance. (5) These results indicate that ganglion cells do not undergo a compensatory change in the segmental innervation they receive when their axons regenerate to targets different from, or in addition to those they originally innervated, even when an entirely new set of ganglionic connexions is formed. This suggests that ganglion cells, or some aspect of their immediate environment, possess a permanent label that determines the segmental innervation they receive.

Animals↗
PubMed1979

Quantitative studies of retinal ganglion cells in a turtle, Pseudemys scripta elegans. I. Number and distribution of ganglion cells.

Multiple pathways for the transmission of visual information from retina to brain have been described in reptiles, but little is known about their functional organization. These parallel channels begin at the retina, and we have therefore begun to study the functional organization of retinal ganglion cells in the turtle, Pseudemys scripta elegans. This paper describes the numbers and distribution of cells in the ganglion cell layer. To develop criteria for the identification of ganglion cells, we labelled them retrogradely by applying horseradish peroxidase (HRP) to the optic nerve. Ganglion cells were found to vary substantially in size and cytology. In low density areas of the retina, ganglion cells typically have cytoplasm with well developed Nissl substance, a distinct, pale nucleus, and a large nucleolus. In high density areas of retina, ganglion cells are small, densely staining, and gliaform. The average minimum proportion of ganglion cells in the ganglion cell layer is 75--80% of total profiles. No more than five or six percent of profiles in the ganglion cell layer are neurons which do not send an axon into the optic nerve (displaced amacrine cells or intraretinal association cells). The ganglion cell layer of P. s. elegans can be divided into a number of regions on the basis of cell density. Isodensity maps constructed from Nissl-stained, wholemounted retinas indicate that there is an elongated region of high ganglion cell density, the visual streak, which extends from nasal to temporal retina and is oriented such that its long axis follows the horizontal axis of the eye. The streak is aligned with the externally visible iris line. Seen in cross-section, the ganglion cell layer in the streak is three to four cells thick; in nonstreak retina, ganglion cells form only a monolayer of somas. Ganglion cell density drops off more rapidly above the streak than below it. The temporal arm of the streak is both shorter and broader than the nasal arm. There is a peak in ganglion cell density at the midpoint of the streak, in the approximate center of the retina. Here, ganglion cell densities exceed 20,000 cells mm-2. The total number of ganglion cells in the retina is 350,000--390,000.

Animals↗
PubMed1993

Ganglions and ganglionic neurons in the cat's larynx.

Localization, projections and role of ganglia and ganglionic neurons in the laryngeal framework were demonstrated in cats. Six to 8 large size ganglia containing 50 to 80 ganglionic neurons per ganglion in the paraglottic space, 4 to 6 small ganglia involving 5 to 25 cells in each ganglion dorsal to the posterior cricoarytenoid muscle, and 1 to 3 small ganglia including 15 to 25 perikarya per ganglion around the inferior laryngeal nerve were observed. Each ganglion showed spindle shaped covering fibrous capsule. Ganglionic neurons totaling 600 to 800 were oval shaped with an average diameter of 25 microns. Projections of the ganglionic neurons to the superior cervical ganglion (SCG) and nodose ganglion (NG) through the ipsilateral internal branch of the superior laryngeal nerve and to periphery were detected. From the dorsal motor nucleus of vagus, SCG and NG, the ganglionic cells received projections ipsilaterally. On immunocytochemistry many vasoactive intestinal polypeptide (VIP)-immunoreactive (ir) neurons, some neuropeptide Y (NPY)- and tyrosine hydroxylase (TH)-ir neurons and a few substance P (SP)-ir cells were recognized in ganglions. VIP-, NPY-, TH-, SP-, and calcitonin gene-related peptide (CGRP)-ir fibers were also observed in and around vessels and glands. Following denervation, VIP-, NPY- and TH-ir neurons and fibers did not change. These results prove that laryngeal ganglionic neurons have endogenic autonomic, especially cholinergic nature and innervate vessels and glands.

Animals↗
PubMedDate not supplied

Stratification of α ganglion cells and ON/OFF directionally selective ganglion cells in the rabbit retina.

The correlation between cholinergic sensitivity and the level of stratification for ganglion cells was examined in the rabbit retina. As examples, we have used ON or OFF alpha ganglion cells and ON/OFF directionally selective (DS) ganglion cells. Nicotine, a cholinergic agonist, depolarized ON/OFF DS ganglion cells and greatly enhanced their firing rates but it had modest excitatory effects on ON or OFF alpha ganglion cells. As previously reported, we conclude that DS ganglion cells are the most sensitive to cholinergic drugs. Confocal imaging showed that ON/OFF DS ganglion cells ramify precisely at the level of the cholinergic amacrine cell dendrites, and co-fasciculate with the cholinergic matrix of starburst amacrine cells. However, neither ON or OFF alpha ganglion cells have more than a chance association with the cholinergic matrix. Z -axis reconstruction showed that OFF alpha ganglion cells stratify just below the cholinergic band in sublamina a while ON alpha ganglion cells stratify just below cholinergic b . The latter is at the same level as the terminals of calbindin bipolar cells. Thus, the calbindin bipolar cell appears to be a prime candidate to provide the bipolar cell input to ON alpha ganglion cells in the rabbit retina. We conclude that the precise level of stratification is correlated with the strength of cholinergic input. Alpha ganglion cells receive a weak cholinergic input and they are narrowly stratified just below the cholinergic bands.

Action Potentials↗
PubMed1991

The topography of magnocellular projecting ganglion cells (M-ganglion cells) in the primate retina.

The projection from the retina to the dorsal lateral geniculate nucleus in the primate arises from two morphologically distinct types of ganglion cells. The P-ganglion cells project to the parvocellular layers, the M-ganglion cells to the magnocellular layers. We have developed a neurofibrillar stain which stains the M-ganglion cell population with a high degree of selectivity allowing us to map their distribution across the retina. As with other ganglion cell types the M-ganglion cell density peaks close to the fovea and declines towards the periphery. At 1 mm from the fovea the proportion of M-ganglion cells ranges from 6 to 10% and then increases to about 8-10% over much of the retina except along the nasal horizontal meridian. Along the nasal horizontal meridian the percentage increases from 10% at 7 mm eccentricity to 20% or more at higher eccentricities. The increased percentage of M-ganglion cells in the nasal quadrant of the retina correlates with the relatively smaller dendritic trees of M-ganglion cells in this region.

Animals↗
PubMed2001

Herpes simplex virus in the vestibular ganglion and the geniculate ganglion-role of loose myelin.

This study presents the first direct evidence for herpes simplex virus type 1 (HSV-1) infection in the neurons of the vestibular ganglion. Although many investigators have reported electron microscopic evidence of HSV-1 infection in sensory ganglia, HSV-1 infection in the vestibular ganglion has not been described. Vestibular ganglion neurons have a unique structure, with a loose myelin sheath instead of the satellite cell sheath that is seen in other ganglia. This loose myelin is slightly different from compact myelin which is known as too tight for HSV-1 to penetrate. The role of loose myelin in terms of HSV-1 infection is completely unknown. Therefore, in an attempt to evaluate the role of loose myelin in HSV-1 infection, we looked for HSV-1 particles, or any effects mediated by HSV-1, in the vestibular ganglion as compared with the geniculate ganglion. At the light microscopic level, some neurons with vacuolar changes were observed, mainly in the distal portion of the vestibular ganglion where the communicating branch from the geniculate ganglion enters. At the electron microscopic level, vacuoles, dilated rough endoplasmic reticulum and Golgi vesicles occupied by virus were observed in both ganglia neurons. In contrast, viral infections in Schwann and satellite cells were observed only in the geniculate ganglion, but not in the vestibular ganglion. These results suggest that loose myelin is an important barrier to HSV-1 infection, and it must play an important role in the prevention of viral spread from infected neurons to other cells.

Animals↗
PubMed1991

Enkephalin-like immunoreactivity in ganglionic cells in the larynx and superior cervical ganglion of the rat.

The distribution of enkephalin-like immunoreactivity (ENK-LI) in the larynx, the superior cervical ganglion (SCG) and the nodose ganglion of adult rats was examined in the present study. A substantial number of the local acetylcholinesterase (AChE)-positive, presumably parasympathetic, ganglionic cells in the larynx displayed ENK-LI. These cells also exhibited neuropeptide Y (NPY)- and vasoactive intestinal polypeptide (VIP)-LI. Varicose nerve fibers showing ENK-LI were observed close to the acini and ducts of the glands, in the perichondrium and in the lamina propria. The varicosities exhibiting ENK-LI frequently displayed NPY- and VIP-LI. The ENK-LI was detected in a subpopulation of AChE-positive nerve fibers in the laryngeal tissue. In the SCG, only a small number of the ganglionic cells displayed ENK-LI. These cells, in contrast to other ganglionic cells of the SCG, did not show NPY-LI. None of the ganglionic cells of the nodose ganglion exhibited ENK-LI. Sympathectomy and vagotomy affected neither the number nor the distribution of fibers showing ENK-LI in the larynx. In conclusion, ENK appears to be present together with NPY and VIP in the parasympathetic innervation of the larynx and in a very limited number of the ganglionic cells of a sympathetic ganglion, the SCG, of the adult rat.

Acetylcholinesterase↗
PubMed1989

Early differentiation of retinal ganglion cells: an axonal protein expressed by premigratory and migrating retinal ganglion cells.

A monoclonal antibody, RA4, was developed that recognizes retinal ganglion cell axons in the mature retina. Between embryonic days 3 and 9, the RA4 antigen was associated with cell bodies in certain regions of the retina in addition to the ganglion cell axons. The RA4-positive cells were of 3 types: an apolar cell adjacent to the ventricular surface, a bipolar cell that spanned the thickness of the retina, and a monopolar cell in the ganglion cell layer. Evidence suggests that these cells are premigratory and migrating retinal ganglion cells. The expression of the RA4 antigen is the earliest indicator of ganglion cell differentiation yet reported. The existence of RA4-positive apolar cells along the outer surface of the retina suggests that the ganglion cell phenotype is expressed as soon as the cell becomes postmitotic. Approximately 20% of the migrating ganglion cells were in pairs. The paired cells most likely arose from the terminal division of a germinal cell. One possibility suggested by these data is that a ganglion cell-specific germinal cell arises from a pluripotent germinal cell. Immunoblots and other analyses revealed the RA4 antigen to be a 140 kDa cytoplasmic protein in the retina. RA4 also recognized many long tract axons in the brain. In the brain, the RA4 epitope was observed on proteins with at least 7 different molecular weights. Evidence suggests that different cell types may express the RA4 antigen with slightly different molecular weights.

Animals↗
PubMed1982

Quantitative studies of retinal ganglion cells in a turtle, Pseudemys scripta elegans: II. Size spectrum of ganglion cells and its regional variation.

Recent evidence suggests that ganglion cell size and its regional variation may be an important feature of vertebrate retinas. Accordingly, we have examined Nissl-stained, whole-mounted Pseudemys scripta retinas to determine the soma size spectrum of ganglion cells at different retinal loci. Cell size histograms reveal that at any given point on the retina, a majority of ganglion cells are small (6-10 microns), and in peripheral samples there is some evidence for a second, larger size class (12-15 microns). Comparison of samples along the dorsoventral and nasotemporal axes suggests that there are two major trends in soma size variation. Along the dorsoventral axis, ganglion cell diameter increases sharply from the visual streak (6-7 microns, cf. Peterson and Ulinski, '79) to the dorsal and ventral periphery (9-10 microns). These changes reflect a tendency toward increased size for the entire distribution as well as a relative decrease in the frequency of small ganglion cells. This soma size variation is significantly correlated with changes in ganglion cell density. Along the nasotemporal axis, temporal ganglion cells are significantly larger than those at more nasal retinal loci. This difference reflects an overall increase in the size of ganglion cells in temporal retina and a small but significant increase in the percentage of neurons larger than 15 microns.

Animals↗
PubMed1985

The structure of the fourth abdominal ganglion of the crayfish, Procambarus clarki (Girard). I. Tracts in the ganglionic core.

The organization of the fourth abdominal ganglion of the crayfish, Procambarus clarki, was studied with the light microscope in serial sections stained with osmium ethyl gallate. This ganglion is composed of a ventral rind of somata and a core of alternating layers of through-tracts and commissures. The longitudinal tracts of the ganglion are named according to the system in use for the orthopteran insects, because the basic plans of the crustacean and insect ventral ganglia exhibit striking anatomical parallels. The dorsal tracts are the largest and the most regular in their path through the ganglion. In the ventral posterior quadrant of the ganglion the tracts diverge from the basic plan to pass around the major synaptic neuropil and the bases of the peripheral nerves. This paper reports the three-dimensional anatomy of the major longitudinal through-tracts, internal tracts and commissures, and bases of peripheral nerves. Landmark features of the ganglion--including the tracts, the major artery of the vascular system, the shape of the ganglionic core in section, and prominent single cells, all of which make it possible to recognize specific regions of the ganglion--are described.

Animals↗
PubMed1991

Intraganglionic portal sinus located between small intensely fluorescent (SIF) cells and principal ganglionic neurons in the inferior mesenteric ganglion of the guinea pig.

The vascular system in the inferior mesenteric ganglion of the guinea pig was studied to clarify the transport pathway of transmitters released by the small intensely fluorescent (SIF) cells to the principal ganglionic neurons. Reconstruction of about 1500 1-micron-thick serial sections of the ganglion demonstrated its portal system. SIF cells were tightly packed and formed two or three clusters under the capsule of the ganglion. Branches from the inferior mesenteric artery ran directly toward these clusters and broke up into a number of coiled and looped sinusoid capillaries among the SIF cells. They then drained into a large sinus surrounding the clusters in the ganglion. Capillaries were derived from this sinus and ramified among the principal ganglionic neurons. After supplying the neurons, these vessels drained into veins surrounding the ganglion. Therefore, as we observed two distinct groups of capillaries, we call this sinus the "intraganglionic portal sinus". All the transmitters secreted from the SIF cells are collected into this intraganglionic portal sinus and are then conveyed through the capillaries to the principal ganglionic neurons.

Animals↗
PubMed1995

Effects of the autonomic ganglion blocking agent hexamethonium on vasodilator responses mediated by the parasympathetic ganglion on the chorda tympani pathway of the cat.

We investigated the pharmacological properties of a parasympathetic ganglion (a chorda tympani ganglion) that mediates vasodilator responses in the lower lip induced by electrical stimulation of the distal cut end of the chorda tympani or facial nerve root of the cat. These responses were suppressed by prior treatment with the autonomic ganglion blocking agent hexamethonium. We compared the effects of three doses of hexamethonium (1, 3 and 10 mg/kg, i.v.) on the chorda tympani ganglion with their effects on three large ganglia; the otic, submandibular and pterygopalatine ganglia that mediate vasodilator responses. Experiments were conducted on 20 cats weighing 1-3 kg which had been anesthetized with a mixture of urethane (100 mg/kg, i.v.) and chloralose (50 mg/kg, i.v.) then artificially ventilated (pancuronium bromide 0.2 mg/kg per h, i.v.). The chorda tympani ganglion's sensitivity to hexamethonium was similar to that of the otic ganglion but differed from the sensitivities of submandibular and pterygopalatine ganglia. We speculate that transmission through the chorda tympani ganglion is pharmacologically similar to the otic ganglion, although its precise location has yet to be determined.

Animals↗