Numerous Ganglia Research Articles

A Case of Mistaken Identity: Doubled Superior Cervical Ganglia

The sympathetic chain serves as a major hub for distribution of both sensory and motor innervation of smooth muscle, cardiac muscle and glands throughout the entire body. The sympathetic chain, along its course from the base of the skull to the tip of the coccyx, includes numerous ganglia that house cell bodies of postsynaptic neurons. The cervical portion of the sympathetic chain includes superior, middle, inferior/stellate and vertebral ganglia. As a group, these ganglia are subject to significant anatomical variation in their location and even presence. While the superior cervical ganglion appears to be the most consistent of these ganglia, there remains a discrepancy in the literature. Specifically, the superior cervical ganglion has been reported to be doubled but this appears to have been perpetuated without clear documentation. This discrepancy was brought to our attention during a detailed dissection of the retropharyngeal region that exposed the superior cervical ganglion and structures at the skull base, including what appeared to be a ganglion anterior to the carotid sheath. This dissection matched exactly the earliest report of a doubled superior cervical ganglion. However, histological examination revealed the mass anterior to the carotid sheath to be a retropharyngeal lymph node. Based on this finding, consistent with large-scale studies of the cervical sympathetic chain, we posit the original observation was of a lymph node and not a doubled superior cervical ganglion.

Is the Measurement of Epicardial Fat in Obese Adolescents Valuable?

Is the Measurement of Epicardial Fat in Obese Adolescents Valuable?

Postnatal development of NADPH-d neurons in the enteric nervous system of the goat

The morphology and distribution of nitric oxide synthase (NOS)-expressing neurons in the myenteric plexus of small intestine of goat at different ages (2 weeks, and 2, 4, 6 and 12 months) were studied by using nicotinamide adenine dinucleotide phosphate-diaphorase (NADPH-d) histochemistry, which could stain NOS-expressing neurons as immunohistochemistry. The results showed that the NADPH-d neurons and their fibres formed a clear tertiary meshwork structure in the myenteric plexus. The shapes of stained neurons were diverse, and many neurons gathered to form numerous ganglia in variable size. During development, the density of NADPH-d neurons in the myenteric plexus of goat small intestine decreased from 27.07/mm2 at 2 weeks to 16.18/mm2 at 12 months. The total number calculated referred to the total serosal surface of small intestine, however, increased from 1.86×106 at 2 weeks to 5.84×106 at 6 months, before decreasing to 4.41×106 at 12 months. At different ages, the density of NADPH-d neurons was lowest, but the total number was highest, in the jejunum with respect to duodenum and ileum. The mean area of the perikaryon or nucleus was enlarged at first and then diminished as the goats growing. The nuclear:cytoplasmic size ratio in NADPH-d neurons at 2 weeks was much higher than that at 2, 4, 6 or 12 months (P<0.05), while no differences could be found among different ages (P>0.05).

On the morphology of the genus Flota Hartman, 1967 and corroboration of family status of Flotidae Buzhinskaja, 1996 (Polychaeta)

Comparative description of the genus Flota is given, including additional data on the anatomical structure of the digestive tract, female gonad, ventral nervous cord, as well as refining of external morphology. The organization of Flota is compared with that of representatives of other families of polychaetes. The arguments for family status of Flotidae are based on features of structure, differentiating Flota from all other polychaetes (tri-ramous non-grooved palps, enormous ventro-lateral pharyngeal organ of peculiar structure and ventral nervous cord with numerous ganglia on connectives). Apart from being differentiated by these characters Flota differs from Flabelligeridae and close families in the structure of the head, digestive tract, parapodia and pygidium, presence of buccal tentacles and surface arrangement of the ventral nervous cord. Discovery of additional specimens of this genus and other representatives of Flotidae, further study of their anatomy and also investigation of the larval development will allow establishing the place of this family among polychaetes.

Location and variability of epicardiac ganglia in human fetuses

The aim of the study was to determine the morphology of epicardiac ganglia in human fetuses at different stages of their development as these ganglia are considered to be of a pivotal clinical importance. Twenty-one fetal hearts were investigated applying a technique of histochemistry for acetylcholinesterase to visualize the epicardiac neural ganglionated plexus with its subsequent stereoscopic examination on total organs. In all of the examined fetuses, epicardiac neural plexus with numerous ganglia was well recognizable and could be clearly differentiated into seven ganglionated subplexuses, topography and structural organization of which were typical for hearts of adult human. The largest ganglion number comprising 77% of all counted ganglia was identified on the dorsal atrial surface. Fetal epicardiac plexus in gestation period of 15-40 weeks contained 929 +/- 62 ganglia, but ganglion amount did vary substantially from heart to heart. In conclusion, this study implies that the human fetal epicardiac ganglia occupy their definitive location already at gestation period from 15 weeks and their number as well as distribution on heart surface presumably is not age dependent.

Parasympathetic control of the heart. II. A novel interganglionic intrinsic cardiac circuit mediates neural control of heart rate

Intracardiac pathways mediating the parasympathetic control of various cardiac functions are incompletely understood. Several intracardiac ganglia have been demonstrated to potently influence cardiac rate [the sinoatrial (SA) ganglion], atrioventricular (AV) conduction (the AV ganglion), or left ventricular contractility (the cranioventricular ganglion). However, there are numerous ganglia found throughout the heart whose functions are poorly characterized. One such ganglion, the posterior atrial (PA) ganglion, is found in a fat pad on the rostral dorsal surface of the right atrium. We have investigated the potential impact of this ganglion on cardiac rate and AV conduction. We report that microinjections of a ganglionic blocker into the PA ganglion significantly attenuates the negative chronotropic effects of vagal stimulation without significantly influencing negative dromotropic effects. Because prior evidence indicates that the PA ganglion does not project to the SA node, we neuroanatomically tested the hypothesis that the PA ganglion mediates its effect on cardiac rate through an interganglionic projection to the SA ganglion. Subsequent to microinjections of the retrograde tracer fast blue into the SA ganglion, >70% of the retrogradely labeled neurons found within five intracardiac ganglia throughout the heart were observed in the PA ganglion. The neuroanatomic data further indicate that intraganglionic neuronal circuits are found within the SA ganglion. The present data support the hypothesis that two interacting cardiac centers, i.e., the SA and PA ganglia, mediate the peripheral parasympathetic control of cardiac rate. These data further support the emerging concept of an intrinsic cardiac nervous system.

Neurons in the chicken ureter are innervated by substance P- and calcitonin gene-related peptide-containing nerve fibres: immunohistochemical and electrophysiological evidence.

Numerous ganglia or single neurones immunoreactive to protein gene-product 9.5 (PGP) were demonstrated in the chicken ureter. Ganglia were observed in the main nerve trunks accompanying the ureter (400-2,000 cells), in the adventitia (1-45 cells; density; 79 +/- 12 ganglia/cm2; mean +/- S.E.M.), in the circular muscle (1-9 cells; 76 +/- 10 ganglia/cm2) and in the longitudinal muscle (1-8 cells; 232 +/- 41 ganglia/cm2). Most of the PGP-positive neurones in the nerve trunk ganglia (approximately 66%) and in the smooth muscle layers (85%) were encircled by a dense plexus of varicose nerve fibres containing both substance P (SP) and calcitonin gene-related peptide (CGRP). SP-positive somata were rarely observed. Immunogold electron microscopy revealed that SP- and CGRP-immunoreactivity were colocalised in the same dense core vesicles. A strong reduction of SP-positive nerve fibres was observed in organ cultures of the ureter, indicating their extrinsic origin. The fibres might originate from the dorsal root ganglia, where SP and CGRP were colocalised in 20-30% of the neurones. The sensitivity of ureteric neurones to SP and CGRP was investigated in recordings obtained from mechanosensitive nerve fibres with cell bodies located in or adjacent to the ureter (U-G units). The majority (71%) of the U-G units was excited by local application of SP in a dose-dependent manner. The SP-sensitive U-G neurones had higher mechanical thresholds (29 +/- 5 mmHg) as opposed to the SP-insensitive ones (10 +/- 3 mmHg). Repeated applications of high doses of SP to the U-G units resulted in desensitisation and reduced the response to mechanical stimuli. None of the U-G units responded to local application of CGRP, but all U-G units were excited by acetylcholine. The data support the hypothesis that SP-containing primary afferents are involved in the modulation of the activity of ureteric neurons in the chicken.

Gross and microscopic anatomy of the vagal innervation of the rat heart.

Intrinsic cardiac ganglia and their vagal innervation are described from gross and microscopic dissections and functional studies in the anesthetized, open-chest, adult rat. Dissecting microscope sketches of the ventral and dorsal aspects of the rat heart provide gross descriptions of the anatomical course of the vagal cardiac nerves. Histological sectioning of adipose tissue packets surrounding the terminal endings of vagal branches distributed to the roots of the great cardiac vessels (aorta, pulmonary artery, precaval veins) revealed clusters of autonomic ganglia. These packets or "fat pads" were located: (1) along the dorsal surface of the right precava and extending medially toward the aortic root, (2) deep to the aortic arch, (3) in the angle between the root of the left precava and the pulmonary artery on the superior-dorsal surface of the left atrium, and (4) in the rostro-dorsal interatrial septum. Vagal distributions of small terminal branches were traced to each of these pads, which contained numerous autonomic ganglia. Electrical excitation of right or left cervical vagus elicited varying degrees of sinus slowing, slowing of A-V conduction, and suppression in atrial contractile force. Very small quantities (0.5 mg in 10 microliters saline) of the ganglionic blocking agent, hexamethonium (C6) were injected selectively into a single fat pad, followed by repetition of right or left vagal stimulation, with careful analysis of changes in heart rate (paced and unpaced), A-V conduction, and contractile force.

Number and density of intrapancreatic ganglion cells in the chicken

The avian pancreas contains numerous small ganglia in nerve bundles within the interlobular connective tissue. The present study assesses the number and density of intrapancreatic ganglion cells in the chicken. The number of ganglion cells in the pancreas was about 14,000 and the density was 18.0 cells/mm3. No ganglion cells were found in the pancreatic islet. The topographical distribution of ganglion cells suggests that they have a closer relationship with the acinus than with the pancreatic islet and, furthermore, closer with B-islets than with A-islets.

Observations on the structure of the subepithelial nerve plexus in the tongue.

The intrinsic innervation of the anterior two thirds of the tongue in adult dogs of both sexes was studied in paraffin sections stained with Bodian, Holmes, cholinesterase and other stains. In all the sections, a subepithelial plexus of nerve fibres and cells was always seen on the dorsum of the tongue. Nerve endings were seen extending in between the epithelial cells on the dorsum of the tongue. The nerve cells were usually spindle-shaped and collected to form numerous ganglia in the submucosa. There were other ganglia in the tongue whose structure was very much similar to terminal autonomic ganglia. The significance of the ganglia consisting of biopolar nerve cells is being discussed.

The distribution of noradrenergic nerves and small, intensely fluorescent (SIF) cells in the cat urinary bladder. A light and electron microscope study.

Fluorescence and electron microscopy have been used to study the distribution of noradrenergic nerves in the smooth muscle of the cat urinary bladder. Using the former technique, relatively few fluorescent noradrenergic nerves were observed in the body and fundus, while a rich plexus occurred adjacent to muscle cells of the bladder neck. The trigone could not be distinguished neuromorphologically from detrusor muscle in this region. Electron microscopy showed that the majority of noradrenergic terminals in the body and fundus were associated with presumptive cholinergic axons, while in the bladder neck noradrenergic terminals formed typical neuroeffector relationships with individual smooth muscle cells. Numerous ganglia occurred both in the adventitia and among the smooth muscle bundles, particularly in the bladder neck. The majority of the nerve cell bodies were non-fluorescent, although many contained bright orange autofluorescent granules, believed to be lysosomes. A small minority of ganglion cells were associated with fluorescent noradrenergic nerve terminals, thereby providing structural evidence for limited intraganglionic inhibition. In addition, occasional groups of small intensely fluorescent (SIF) cells were observed in some intramural ganglia and these were subsequently identified in the electron microscope. The possibility that these cells may provide a second inhibitory influence on bladder activity was considered.

Histological, acetycholinesterase, and fluorescence histochemical studies on the atrial ganglia of the monkey heart

Silver staining, acetycholinesterase, and fluorescence histochemical studies on the atrial septum of the monkey heart reveal the presence of numerous ganglia, specially in the region of the coronary sinus and the fossa ovalus and near the origin of the great vessels. Three types of neurons were seen in the ganglia: first, a group of large multipolar neurons with a deeply impregnated cytoplasm; second, light silver-staining neurons possessing one or two processes; and finally, an intermediate neuron characterized by a large densely silver-impregnated nucleus which contrasted markedly with the pale cytoplasm. In addition, the ganglia contained “argyrophilic particles” composed of a body and single elongated process. The majority of the neurons were acetycholinesterase-positive; however, the acetycholinesterase staining reaction showed considerable variation. At one end of the spectrum the ganglia were so intensely stained that all intraganglionic detail was lost; whereas, in others the acetycholinesterase reaction was barely visible. The specific fluorescence studies demonstrated that a few of the neurons contained an autofluorescent granular cytoplasm. The fluorescence of these cells was enhanced after exposure to paraformaldehyde, and this increase in fluorescence could be interpreted as either an enhancement of the autofluorescence or evidence for the existence of a system of adrenergic neurons in the heart. The significance of these findings and the relationship to sensory nerves, and the sympathetic and parasympathetic nervous system are discussed.

An Embryological Study of Human Suprarenal Glands and ZUCKERKANDL's Paraganglia

The results of my study on the suprarenal glands of early stage human embryo based on their silver-impregnated specimens may be summarized as follows.In my 20mm embryo, the plexus solaris containing numerous ganglia was found fairly well developed between the cortical body of rather large size and the aorta abdominalis. The sympathicoblasts in these ganglia, however, are round cells far smaller than the cortical cells and packed very closely. Very fine nerve fibres have been discovered amoug the groups of such cells, but their relation to the smypathicoblasts could not be made out with any certainty, for no neurofibrils were formed in the cell bodies and consequently no nerve processes were in formation. Thus, these blastocytes are nothing but uniform and entirely undifferentiated primitive cells. Accordingly, no ganglion cells, mantle cells or SCHWANN's cells are yet born.Such ganglia of primitive sympathetic cells are formed also on the medial side of the cortical body, out of which the cells immigrate further into the deeper part of the cortical stock. The immigration in this stage of embryonic life is advanced so little that its beginning may be probably set at a time short before this stage.In my 40mm embryo, the plexus coeliacus and the plexus suprarenalis become better developed and the ZUCKERKANDL's paraganglia also comes into incipient formation. The sympathetic cells in the ganglia of the plexus, however, show as yet no trace of differentiation. Only the nerve fibres running among them come to show strong silver-afffinity.The immigration from the vicinity of the cortical body into its inner part of the sympathetic cells accompanying nerve fibres is now very perceptible, and some cell groups are detected in sporadic existence in the central part of the body, the small cells in the groups being easily distinguishable from the far larger cortical cells. Such cells of the immgrating hordes sometimes penetrate as far as into the center of the cortical body by this stage, but yet no differention of them into medullar cells or ganglion cells sets in.The abdominal paraganglia quite identical in nature with the medullar tissue are found in incipient formation within the plexus solaris and around the abdominal aorta. The cells in these paraganglia are rather light large cells and a considerable number of nerve fibres showing more or less frequent change in size are found in these paraganglia.In my 80mm fetus, the nerve elements in the suprarenal plexus and the adrenal medulla originting therein show a considerably advanced differentiation. In the suprarenal plexus, the ganglion cells begin to send out nerve processes and to show the mutipolarity specific to the sympathetic ganglion cells. The development of such processes, however, is as yet very poor. SCHWANN's cells appear sporadically alongside the nerve fibres, but no mantle cells are yet to be formed around the nerve cells.In this stage, the suprarenal gland undergoes very interesting changes as follows. The suprarenal medulla enlarges in the central part of the gland, extending over an area somewhat larger than that of the certex in cross-section. The sympathetic cells begin to show differentiation and their suddenly inflated bodies are found containing granules probably showing ohromaffinity, while the cortical cells are reduced into small cells, large cells being found no more. The medullar tiasue comes to contain numerous nerve fibres, of which the terminal mode assimilates that in human adults. Groups of spmpathetic cells as yet utterly undifferentiated may be found here and there in the medullar tissue. These groups later on become the ganglia found in the medullar tissue in all probaility.

On the ganglia and nerves of the virgin uterus

The author states that his recent dissections have enabled him to verify the descriptions he gave of the ganglia and nerves of the uterus in his papers already published in the Philosophical Trans­actions, and also to detect the existence of ganglia situated in the muscular coat of the uterus, and of plexuses of nerves accompanying all the blood-vessels and absorbents ramifying in its walls, between the peritoneum and lining membrane. By examining the hearts of a fœtus, of a child of six years of age, of an adult in the sound state, a human heart greatly hypertrophied, and the heart of an ox, he found that there exists a striking analogy between the ganglia and nerves of the uterus and those of the heart. He ascertained by microscopic observation that the muscular and vascular structures of the auricles and ventricles are endowed with numerous ganglia and plexuses of nerves, which, as far as he knows, have not yet been described, and which enlarge simultaneously with the natural growth of the heart, and also continue to enlarge during its morbid condi­tions of hypertrophy. The author also finds that the size of the ganglia and nerves of the left auricle and ventricle, in the normal state, is more than double that of the corresponding parts on the right side. A description is then given of two elaborate drawings which accompany the paper.

On the nervous system of the heart

The author premises a historical notice of the various opinions entertained by distinguished anatomists respecting the nerves of the heart; some having maintained that the human heart is copiously supplied with nerves, and others that it has few or none. In September 1846, the author resolved to dissect, under the microscope, the nerves of the heart while covered with alcohol, as he had done those of the uterus. His examinations of the fœtal heart, of the heart of a child at the age of six years, of the heart of an adult in the sound state, of the human heart greatly hypertrophied, and of the heart of the ox, warrant, he thinks, the following conclusions:—1st, that the blood-vessels and the muscular structure of the auricles and ventricles of the heart are furnished with numerous ganglia and plexuses of nerves which have hitherto been neither described nor represented by any anatomist; 2ndly, that these nervous structures of the heart, which are distributed over its surface and throughout its walls to the lining membrane and columnæ carneæ , enlarge with the natural growth of the heart before birth, and during childhood and youth, until the heart has attained its full size in the adult; 3rdly, that when the walls of the auricles and ventricles are affected with hypertrophy, the ganglia and nerves of the heart are enlarged like those of the gravid uterus; and 4thly, that the ganglia and nerves which supply the left auricle and ventricle in the natural state, are more than double the size of the ganglia and nerves distributed to the right side of the heart. The author observes that the ventricles and auricles of the human heart and of those of the hearts of the larger quadrupeds, are covered with two distinct membranes; the exterior is the serous membrane, connected by cellular tissue with another distinct tunic, which has scarcely, if at all, been noticed by anatomists. This second membrane is stated to have a dense fibrous structure, to be semitransparent, and to resemble in a remarkable manner the aponeurotic expansions, or fascice, covering muscles in other parts of the body; and, like them, it sends numerous fibres or processes between the muscular fasciculi, blood-vessels, nerves, and adipose substance of the heart. This membrane, the author thinks, may appropriately be termed the cardiac fascia , and he states that, through this, after the removal of the serous membrane, there are numerous ganglia and plexuses of nerves visible to the naked eye. If these nerves be traced backwards towards the base of the ventricles, they are seen to terminate in a great ganglionic plexus, situated between the pulmonary artery and aorta; into which plexus branches of nerves enter from the par vagum of each side, the recurrent and the sympathetic nerves. From this great ganglionic plexus, which the author considers to be the root of all the principal cardiac nerves, branches invested with a soft neurilema proceed to the auricles and ventricles, and their septa. Large flat branches of nerves pass from this ganglionic mass to the coronary arteries, the trunks of which they completely surround like a sheath, and all the ramifications of which they accompany, not only over the surface of the heart, but into the muscular substance, and they are distributed with these arteries throughout its walls to the lining membrane. The author also states that there are besides numerous branches of nerves from the great ganglionic plexuses at the base of the heart and surrounding the coronary arteries, with ganglia distributed over the surfaces of both the ventricles, which do not accompany the blood-vessels, but run obliquely across them, and also across the fibres of the muscular coat. These superficial cardiac nerves are described as being remarkably soft, flat, of a grey colour, and somewhat transparent, as had been formerly stated by Scarpa. Towards the left side and apex of the left ventricle, these nerves lie in grooves or depressions of the muscular coat, and spread out into ganglionic enlargements, from which innumerable filaments are sent off laterally to the muscular coat. There are ganglia of considerable size on these superficial nerves where they are crossing the arteries, which send branches to the coats of the vessels, and some of which branches pass down with the vessels into the substance of the heart.

On the ganglia and nerves of the heart, with two drawings

The author states that since his former communication was presented to the Royal Society he has made a very minute dissection in alcohol of the whole nervous system of the young heifer’s heart. In this preparation the distribution of the ganglia and nerves over the entire surface of the heart, and the relations of these structures to the blood-vessels and muscular substance, are considered by the author to be far more fully displayed than in any of his former dissections. He states, that on the anterior surface there are distinctly visible to the naked eye, ninety ganglia or ganglionic enlargements on the nerves, which pass obliquely across the arteries and the muscular fibres of the ventricles from their base to the apex; that these ganglionic enlargements are observed on the nerves, not only where they are crossing the arteries, but where they are ramifying on the muscular substance without the blood-vessels ; that on the posterior surface the principal branches of the coronary arteries plunge into the muscular substance of the heart near the base, and many nerves with ganglia accompany them throughout the walls to the lining membrane and columnæ carneæ. The author considers that, in the accompanying beautiful drawings, Mr. West has depicted with the greatest accuracy and minuteness the whole nervous structures demonstrable in this preparation on the surface of the heart; but that the ganglia and nerves represented in these drawings constitute only a small portion of the nervous system of the heart, numerous ganglia being formed in the walls of the heart which no artist can represent.

IV. Postscript to a paper “On the ganglia and nerves of the heart.”

Since the communication above referred to was presented to the Royal Society, I have made a very minute dissection in alcohol of the whole nervous system of the young heifer’s heart. The distribution of the ganglia and nerves over the entire surface of the heart, and the relations of these structures to the blood-vessels and muscular substance, are far more fully displayed in these preparations than in any of my former dissections. On the anterior surface, there are distinctly visible to the naked eye ninety ganglia or ganglionic enlargements on the nerves, which pass obliquely across the arteries and the muscular fibres of the ventricles from their base to the apex. These ganglionic enlargements are observed on the nerves, not only where they are crossing the arteries, but where they are ramifying on the muscular substance without the blood-vessels. On the posterior surface, the principal branches of the coronary arteries plunge into the muscular substance of the heart near the base, and many nerves with ganglia accompany them throughout the walls to the lining membrane and columnse carneæ. From the sudden disappearance of the chief branches of the coronary arteries on the posterior surface, the nervous structure distributed over a consider­ able portion of the left ventricle is completely isolated from the blood-vessels, and on these, numerous ganglionic enlargements are likewise observed, but smaller in size than the chains of ganglia formed over the blood-vessels on the anterior surface of the heart. In the accompanying beautiful drawings, Mr. West has depicted with the greatest accuracy and minuteness the whole nervous structures demon­strable in these preparations on the surface of the heart. But the ganglia and nerves represented in these drawings constitute only a small portion of the nervous system of the heart, numerous ganglia being formed in the walls of the heart which no artist can represent. It can be clearly demonstrated that every artery distributed throughout the walls of the Uterus and Heart, and every muscular fasciculus of these organs, is supplied with nerves upon which ganglia are formed.