Nerves and nerve plexuses of the human vertebral column

The origin, distribution, and termination pattern of nerves supplying the vertebral column and its associated structures have been studied in the human fetus by means of an acetylcholinesterase whole-mount method. The vertebral column is surrounded by ventral and dorsal nerve plexuses which are interconnected. The ventral nerve plexus consists of the nerve plexus associated with the anterior longitudinal ligament. This longitudinally oriented nerve plexus has a bilateral supply from many small branches of the sympathetic trunk, rami communicantes, and perivascular nerve plexuses of segmental arteries. In the thoracic region, the ventral nerve plexus also is connected to the nerve plexuses of costovertebral joints. The dorsal nerve plexus is made up of the nerve plexus associated with the posterior longitudinal ligament. This nerve plexus is more irregular and receives contributions only from the sinu-vertebral nerves. The sinu-vertebral nerves originate from the rami communicantes and, in the cervical region, also from the nerve plexus of the vertebral artery. Thick and thin sinu-vertebral nerves are found. Most frequently three types of thick sinu-vertebral nerves are observed, i.e., ascending, descending, or dichotomizing ones. Finally, the distribution of the branches of the ventral and dorsal nerve plexuses and of the sinu-vertebral nerves is described.     

Light microscopic studies of concanavalin A binding in the choroid plexus epithelium and ependymal cells of the cerebral ventricle and human tumors derived from those tissues

Histochemical investigations of human choroid plexus with lectins revealed strong cytoplasmic binding of concanavalin A to plexus epithelium, whereas ependymal cells were unstained or only weakly reactive. A similar but less clear-cut staining pattern by concanavalin A was observed with plexus papillomas and ependymomas. A clear discrimination however, between the two tumor types using this method is not possible.     

Influence of dehydratation on glycerophosphorylcholine and choline distribution along the rat nephron

Glycerophosphorylcholine is one of the four major organic osmolytes in renal medullary cells, changing their intracellular osmolyte concentration in parallel with extracellular tonicity during cellular osmoadaptation. In this study, the tubular content of glycerophosphorylcholine was quantified in untreated and 48-h-dehydrated male rats. A chemiluminescence ultra-micromethod was developed to measure choline at the picomolar level in single tubules microdissected from collagenase-treated kidneys. The glycerophosphorylcholine level was calculated as the difference between total choline after acid hydrolysis and the free tubular choline content. In accordance with the glycerophosphorylcholine distribution pattern in different renal zones of untreated rats, low amounts of glycerophosphorylcholine were found in all cortical and outer medullary structures (< 35 pmol/mm), whereas increasing amounts were detected towards the papillary tip (163 pmol/mm). As a percentage of total choline, the level of free tubular choline varied from 4.2% in outer medullary proximal tubules to 30.3% in the inner medullary collecting ducts adjacent to the outer medulla (IMCD1). Antidiuresis led to a nearly twofold increase in glycerophosphorylcholine content in papillary collecting ducts. The osmolality-dependent regulation of organic osmolytes in single microdissected tubules has been demonstrated for the first time. Furthermore, the high tubular glycerophosphorylcholine concentration compared to sorbitol and myo-inositol emphasizes the predominance of glycerophosphorylcholine in the inner medulla and papilla of the rat kidney.     

Trypanosoma brucei brucei: a model for cerebral trypanosomiasis in mice--an immunological, histological and electronmicroscopic study.

The successful induction of cerebral trypanosomiasis in ordinary laboratory mice using Trypanosoma brucei brucei is reported. Sequential studies demonstrated the presence of trypanosomes in the interstitium of the choroid plexus at the fourth week after infection which correlated with the appearance of anti-trypanosomal antibodies, a rise of IgM and IgG serum levels and a rise of Clq binding activity as well as a decrease of C3 levels. Electronmicroscopic studies showed that the parasites were flagellated and localized extracellularly mainly in the interstitium of the choroid plexus. Granular immunofluorescent deposits of Ig and C3 were most marked in the choroid plexus. Electron-dense deposits suggestive of immune complexes were seen in subendothelial, interstitial and subependymal areas of the choroid plexus. Since autoantibodies to the brain were found in the serum of some mice, the possible involvement of autoimmune manifestations in the pathogenesis of cerebral lesions has to be considered. The pattern of inflammatory foci at the eighth week after infection was very similar to that observed in cerebral African trypanosomiasis in man. After treatment with ethidium bromide, trypanosomes persisted in the tissues when circulating parasites could no longer be detected. These observations suggest a sequential involvement of brain structures during African trypanosomiasis. Trypanosomes may first migrate from the vascular compartment into the interstitium of the choroid plexus, possible favoured by increased vascular permeability. Circulating immune complexes and complement activation may be involved at this state. Trypanosomes localized in the choroid plexus may then trigger a local immunologically mediated inflammatory reaction favouring the migration of trypanosomes into the CSF and further invasion of other cerebral structures.     

Development of the sympathetic innervation to the cerebral arterial system in neonatal rats as revealed by anterograde labeling with wheatgerm agglutinin-horseradish peroxidase

In order to clarify the developmental pattern in the sympathetic nerve fibers innervating the cerebral arterial system during the postnatal period in rats, we labeled the postganglionic nerve fibers originating in the superior cervical ganglion (SCG) and directly observed their extension and plexus formation by means of anterograde labeling with wheat germ agglutinin-horseradish peroxidase (WGA-HRP). The WGA-HRP solution was injected into the right SCG 1–7 days after birth. The rats were killed 48 h after trace injection, and the cerebral arteries were reacted with tetramethylbenzidine, then observed as a whole mount preparation. The labeled nerve fibers appeared as a few relatively straight bundles with branching fibers running longitudinally to the long axis of the artery in the ipsilateral right side of the circle of Willis and proximal portion of their main branching arteries at 3 days after birth. The nerve fibers started to form a circular pattern of nerve plexus only on the wall of the circle of Willis as early as 1 week after birth. At the beginning of postnatal week 2, labeled nerve fibers extended the collateral projections into the collateral side of the circle of Willis, and these expanding projections could not be observed at postnatal week 3. We observed a route of the sympathetic nerve fibers advancing into the cerebral arterial system which has not been described in previous studies; bundle of labeled nerve fibers entered into the wall of the middle portion of the basilar artery in half of the animals, in any postnatal period. We were able to confirm, by using an anterograde labeling technique with WGA-HRP, how the sympathetic nerve fibers advance into the cerebral arterial system, when they start to form nerve plexus during the postnatal period in rats, and clarified that the sympathetic nerve fibers showed overabundant collateral projection in the cerebral arterial system during the early postnatal period.     

Blood Flow Patterns Spatially Associated with Platelet Aggregates in Murine Colitis

In the normal murine mucosal plexus, blood flow is generally smooth and continuous. In inflammatory conditions, such as chemically‐induced murine colitis, the mucosal plexus demonstrates markedly abnormal flow patterns. The inflamed mucosal plexus is associated with widely variable blood flow velocity as well as discontinuous and even bidirectional flow. To investigate the mechanisms responsible for these blood flow patterns, we used intravital microscopic examination of blood flow within the murine mucosal plexus during dextran sodium sulphate‐and trinitrobenzenesulfonic acid‐induced colitis. The blood flow patterns within the mucosal plexus demonstrated flow exclusion in 18% of the vessel segments (P < 0.01). Associated with these segmental exclusions was significant variation in neighboring flow velocities. Intravascular injection of fluorescent platelets demonstrated platelet incorporation into both fixed and rolling platelet aggregates. Rolling platelet aggregates (mean velocity 113 μm/sec; range, 14–186 μm/sec) were associated with reversible occlusions and flow variations within the mucosal plexus. Gene expression profiles of microdissected mucosal plexus demonstrated enhanced expression of genes for CCL3, CXCL1, CCL2, CXCL5, CCL7, CCL8, and Il‐1b (P < 0.01), and decreased expression of CCL6 (P < 0.01). These results suggest that platelet aggregation, activated by the inflammatory mileau, contributes to the complex flow dynamics observed in acute murine colitis. Anat Rec, 292:1143–1153, 2009. © 2009 Wiley‐Liss, Inc.     

Microarterial pattern of human kidney

The study of microarterial pattern of human kidney by Butylbuterate and Microfil Silicone Rubber compound cast technique has been carried out. The arcuate arteries and their major intrarenal branches were seen running in the tissue tunnels (the area devoid of glomeruli and capillary plexus) not observed by any other worker in the field. The aglomerular giant arterioles arising from arcuate and interlobar arteries were observed. Afferent arteriole feeds glomerulus and afferent breaks up into capillary plexus. Aglomerular afferents have also been observed. Glomeruli were distributed right underneath the renal capsule. Vasa-recta, from arcuate artery and capillary plexus at the corticomedullary junction were running almost a straight course deep into the medulla unlike the observations of Castelli and Huelke (1968) who noticed the tortuous course. However the present study revealed that the vasa-recta become highly tortuous when they terminate by anastomosing with each other at the apex of the renal papilla. When a major artery pierces through the vasa-recta bundle near corticomedullary junction, the bundle divides into 2 and each half arches round that vessel to continue as a single bundle.     

Expression of type VII collagen,the major anchoring fibril component,in normal and neoplastic human nervous system

The distribution of type VII collagen was examined in the normal human nervous system, in brain tumour biopsies and in glioma cell lines by immunohistochemistry and western blotting. In normal tissue, positivity was observed beneath choroid plexus epithelial cells and around pineal gland and pituitary gland cell nests, while other brain regions and peripheral nerves were negative. Expression was preserved in most related tumours (choroid plexus papilloma, pineoblastoma, pituitary adenoma). Scattered abnormal vessels showed neoexpression of type VII collagen in about half of the astrocytic and ependymal tumours. Glioma cells in situ were consistently negative for type VII collagen, where-as the glioblastoma cell lines were positive. Our results suggest that anchoring fibrils or at least epitopes of their major structural component are present in normal and pathological cerebral structures, indicating a unique distribution of type VII collagen in the nervous system.     

The human choroid plexus and autoimmune nephritis.

The choroid plexus resembles the glomerular basement membrane (GBM) and may be a site of injury or source of antigen in Goodpasture syndrome. Immunohistologic studies were performed on the choroid plexus of a patient with auto-immune nephritis and pulmonary hemorrhage. The studies showed linear deposition of host IgG, IGM, and beta1c. Antibody eluted from the diseased kidney fixed in a linear pattern to normal choroid plexus and could be absorbed by either choroid plexus or GBM. Antibody to choroid plexus fixed to GBM and the linear staining was no longer observed after absorption with GBM or choroid plexus. Antibody to GBM fixed to normal choroid plexus and was obsorbed by both choroid plexus and glomerular basement membrane. The studies suggest an immunologic relationship between choroid plexus and GBM and a role for the choroid plexus in autoimmune nephritis.     

Growth of dissociated neurons in culture dishes coated with synthetic polymeric amines

The distribution of Met5-enkephalin-Arg6-Phe7 (Met-Enk-Arg-Phe)-like immunoreactivity in the rat gastrointestinal tract was studied by immunohistochemical techniques. Antiserum against a Met-Enk-Arg-Phe-thyroglobulin conjugate was raised in rabbits and was found to be specific for synthetic Met-Enk-Arg-Phe. Met-Enk-Arg-Phe-like immunoreactivity was found in neuronal structures in all parts of the rat gastrointestinal tract. Immunostained somata were primarily located in myenteric plexus; immunostained processes were mostly present in myenteric plexus and circular muscle layer. This distribution pattern is similar to that of the three other opioid polypeptides, Met5-enkephalin, Leu5-enkephalin and Met5-enkephalin-Arg6-Gly7-Leu8.     

Serotonin distribution in the circumventricular organs of the rat. An immunohistochemical study

Serotonin-immunoreactive structures in the circumventricular organs (organum vasculosum laminae terminalis, subfornical organ, subcommisural organ and area postrema) of the rat were demonstrated using a modified peroxidase-antiperoxidase immunohistochemical method. Various densities of serotonin fibers were demonstrated in all four circumventricular organs; however, serotonin-positive cells were evident in the area postrema only after nialamide treatment. Serotonergic supraependymal fibers were observed on the surface of the organum vasculosum laminae terminalis and that of the subfornical organ, but not on the subcommissural organ and area postrema. The organ, but not on the subcommissural organ and area postrema. The serotonergic plexus of the basal portion of the subcommisural organ was considered to be continuous with the supraependymal plexus.     

P物质、血管活性肠肽和乙酰胆碱能神经在大鼠肠道内的分布及其关系

应用乙酰胆碱酯酶(AChE)组织化学和PAP免疫组织化学方法,比较观察P物质(SP)、血管活性肠肽(VIP)和AChE三种阳性神经元在大鼠十二指肠、空肠、回肠、结肠和直肠内的分布特征及其相互关系。结果显示:SP、VIP、AChE阳性神经神经元和纤维均分布于肠壁各层,从十二指肠、空肠到回肠逐渐增多,但从结肠到直肠则逐渐减少;AChE阳性神经元或纤维在肠壁各层最丰富,其中VIP以粘膜层和粘膜下神经丛较丰富,SP以肠肌丛较丰富;三者的分布密度为AChE>VIP>SP。AChE、SP和VIP阳性神经元胞体及神经纤维在不同肠段的分布密度有明显差异(P<0.05),提示可能与不同肠段肠动力调节功能有关。     

Examination of microvascular structures of midcortical region in sheep kidneys: a three dimensional approach

Polyester-crystic cast was observed to reach the peritubular capillary plexus following injection in sheep kidneys. Microvascular structures in this region are also reported in this study. Glomeruli were found to vary in size and shape. Diameters of afferent arterioles were larger than those of efferent arterioles. The glomerulus is supplied by more than one afferent arteriole, and in some regions, the blood in afferent arterioles joins collateral circulation via the intercapillary plexus. Morphological properties at the end of the peritubular capillary plexus were found to be remarkably significant.     

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 μm in the rostrocaudal direction, and about 200 μm 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 μm in the rostrocaudal direction and about 400 μm 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.     

The Contribution of the Left Phrenic Nerve to Innervation of the Esophagogastric Junction

The contribution of the left phrenic nerve to innervation of the esophagogastric junction. The esophagogastric junction is part of the barrier preventing gastroesophageal reflux. We have investigated the contribution of the phrenic nerves to innervation of the esophagogastric junction in humans and piglets by dissecting 30 embalmed human specimens and 14 piglets. Samples were microdissected and nerves were stained and examined by light and electron microscopy. In 76.6% of the human specimens, the left phrenic nerve participated in the innervation of the esophagogastric junction by forming a neural network together with the celiac plexus (46.6%) or by sending off a distinct phrenic branch, which joined the anterior vagal trunk (20%). Distinct left phrenic branches were always accompanied by small branches of the left inferior phrenic artery. In 10% there were indirect connections with a distinct phrenic nerve branch joining the celiac ganglion, from which celiac plexus branches to the esophagogastric junction emerged. Morphological examination of phrenic branches revealed strong similarities to autonomic celiac plexus branches. There was no contribution of the left phrenic nerve or accompanying arteries from the caudal phrenic artery in any of the piglets. The right phrenic nerve made no contribution in any of the human or piglet samples. We conclude that the left phrenic nerve in humans contributes to the innervation of the esophagogastric junction by providing ancillary autonomic nerve fibers. Experimental studies of the innervation in pigs should consider that neither of the phrenic nerves was found to contribute. Clin. Anat. 33:265–274, 2020. © 2019 Wiley Periodicals, Inc.     

Pathological and immunohistochemical studies of choroid plexus carcinoma of the dog

Choroid plexus carcinomas in four dogs (three male, one female) aged small middle 2.5 to 10 years, were examined by light microscopy and immunohistochemistry. The dogs showed progressive neurological signs including ataxia, seizures, vestibular disease and cranial nerve deficits, lasting for several months in some cases. Primary tumours were localized in the lateral (one case), third (one case), and fourth (two cases) ventricles. Hydrocephalus was evident at post-mortem examination in one case. In two cases the neoplastic cells closely resembled the structure of normal choroid plexus, with a distinct papillary pattern, composed of well-differentiated columnar epithelium. In the other two cases, cellular pleomorphism, nuclear atypia, increased mitotic activity and necrosis were observed. In all cases, dissemination of neoplastic cell clusters was detected within the subarachnoid space or the ventricular cavity. Immunohistochemical examination showed a multifocal labelling pattern for pankeratin and cytokeratin AE1 and diffuse vimentin positivity in poorly differentiated tumours. Well-differentiated choroid plexus carcinomas showed multifocal immunoreactivity for cytokeratin AE3, multifocal to diffuse immunoreactivity for vimentin and occasional positivity for carcinoembryonic antigen. Epithelial membrane antigen, Ber EP4 and S-100 were negative in all cases. Glial fibrillary acidic protein labelling occurred only in a single, poorly differentiated tumour. Occasional reactions for proliferating cell nuclear antigen and MIB-1 were seen in two cases. It was concluded that at least two morphological and possibly phenotypic subtypes (well-differentiated and anaplastic) of choroid plexus carcinoma of the dog could be identified.     

Variations of the ventral rami of the brachial plexus.

We studied the variations in the ventral rami of 152 brachial plexuses in 77 Korean adults. Brachial plexus were composed mostly of the fifth, sixth, seventh and eighth cervical nerves and the first thoracic nerve (77.0%). In 21.7% of the cases examined, the fourth, fifth, sixth, seventh and eighth cervical and the first thoracic nerves contributed to the plexus. A plexus composed of the fourth, fifth, sixth, seventh and eighth cervical and the first and second thoracic nerves, and a plexus composed of the fifth, sixth, seventh eighth cervical nerves were also observed. The plexuses were classified into three groups according to cephalic limitation, and the plexus of group 2 in which the whole fifth cervical nerve enters the plexus, were observed the most frequent. The average diameter of the sixth and the seventh cervical ventral rami of the plexus was greatest and that of the fifth cervical was smallest. The largest nerve entering the plexus was the sixth or the seventh cervical nerve in about 79% of cases. The dorsal scapular nerve originated from the fifth cervical ventral ramus in 110 cases (75.8%). The long thoracic nerve was formed by joining of roots from the fifth, sixth, and seventh cervical nerves in 76.0% of cases. Also, a branch to the phrenic nerve, the suprascapular nerve, a nerve to the pectoralis major muscle and a nerve to the subscapular muscle arising from the ventral rami of the plexus were observed.     

Ramifications of the globus pallidus in the rat as indicated by patterns of immunohistochemistry

An attempt has been made to redefine the borders of the globus pallidus by the aid of the unique pattern of enkephalin-like and substance P-like immunoreactivity characterizing the pallidum of both monkey and rat. In preparations immunoreacted for these two peptides by the peroxidase-antiperoxidase histochemical method of Sternberger this pattern appears in the form of ribbon-like fibers (here called "woolly fibers") that have been interpreted by Haber and Elde as unstained pallidal elements (dendrites and cell bodies) each enmeshed by a plexus of thin, enkephalin- or substance P-positive striatopallidal fibers. A dense enkephalin-positive woolly-fiber plexus fills the entire external pallidal segment as conventionally defined (here called "dorsal pallidum") and extends from there in various, generally ventral, directions. The most massive, rostral extension defines the subcommissural or "ventral pallidum" of Heimer and Wilson and expands from there ventraward into the olfactory tubercle, supporting Heimer's suggestion that many of the large cells of the tubercle are pallidal neurons. Further extensions from the enkephalin-positive dorsal pallidum plexus invade the ventral striatal region (including the nucleus accumbens), a dorsal region of the amygdala, and the bed nucleus of the stria terminalis. Substance P-positive woolly fibers, like their enkephalin-positive counterparts, fill the ventral pallidum and invade the olfactory tubercle, but avoid all except a small rostroventral part of the dorsal pallidum, and do not invade the striatum, the amygdala, or the bed nucleus of the stria terminalis. On the other hand, the dense substance P-positive woolly-fiber plexus filling the internal pallidal segment (entopeduncular nucleus) expands medialward into the lateral hypothalamic region. The entopeduncular nucleus invades the hypothalamus also with a loose plexus of enkephalin-positive woolly fibers. It is suggested that woolly fibers extending outward beyond the conventionally recognized borders of the pallidum represent pallidal elements innervated by enkephalin or substance P-positive fibers arising from ventromedial striatal regions in turn innervated by limbic structures.     

Bilateral multiple complex variations in the formation and branching pattern of brachial plexus

Bilateral variations in the formation and branching of brachial plexus are extremely rare. Multiple bilateral variations in brachial plexus right from divisions to branching pattern were observed during the dissection in an adult male cadaver. Lateral and medial cord formation showed deviation from the usual pattern. Anterior division of upper trunk continued as lateral cord. Medial cord was formed by the union of anterior division of lower trunk and anterior division of middle trunk, thus receiving fibers from both the trunks. Anterior division of middle trunk bifurcated into upper and lower branches. We encountered two lateral roots bilaterally and two medial roots of median nerve on the left side with anomalous origin. There were three upper subscapular nerves on the left and two on the right side with variations in their origin. Anomalous origin of many other branches on both sides was encountered. It is extremely uncommon to find so many variations in one body and bilateral variations are still too rare. Understanding of such variations is clinically important for diagnosing unexplained clinical signs and symptoms as well as during nerve blocks and certain surgical procedures around the neck and proximal arm.