Variability in the myeloarchitectonics of the nerves of the thyroid arteries during postnatal human development

Serial transversal sections on the nerve-vascular complexes of four thyroid arteries in newborns, in persons of the 1st and 2d periods of mature age, in elderly and old persons (40 complexes in each age group) are stained after Weigert--Pahl. Amount of myelin fibers (MF) of three dimensional classes are defined micromorphometrically. Total amount of the MF in the nerves of all thyroid plexuses is the greatest in the persons belonging to the second mature period of age: it is 2.7 times as great as in the newborns. In the elderly persons it is 1.5 times, and in the old persons--1.8 times as little as in the persons of the second period of maturity. Thin MF make the absolute majority. The amount of the MF with middle caliber in the thyroid nerves of the mature persons is 6.6 times as great as in the newborns. Their amount in the old persons is 1.7 times as little as in the mature persons. Thick MF are absent in the newborns; in the mature and elderly persons they are observed now and then. The thick MF are characterized by a high variation coefficient (up to 84%). According to the criteria of absolute and relative contents of both total and group composition of the MF in postnatal period, three stages in development of the thyroid innervational connections performed by the MF are revealed: productive, stabilization and involution. The correlative analysis reveales a direct dependence in the system diameter of each thyroid artery--number of the MF in nerves of its plexus in the newborns and mature persons. This dependence becoms negative in the elderly and old persons.(ABSTRACT TRUNCATED AT 250 WORDS)     

Age and features of the content of myelinated fibers in nerves of the splenic plexus of man

The amount of the myelin fibers (MF) has been calculated in transversal serial sections of the nervous-vascular complexes of the splenic artery in newborns, in persons of mature (the 1st and 2d periods), elderly and old ages. In each age group 20 complexes have been studied. The total amount of the MF in persons of mature age (the 1st period) in 4.2-6 times greater (initial--terminal parts of the plexus) than in newborns, in the persons of old age it is 4-2.1 times less than in persons of mature age (in both cases P less than 0.001). Thin MF predominate, their relative contents in the aggregate of all classes of the MF in newborns are 92%, in mature persons--87%, in old persons--65%. Decreasing part of the thin MF together with increase of their absolute amount in the mature persons, comparing to the newborns, depends on higher rates in differentiation of middle and thick MF. Phenotyping peculiarities and stages of productive development, stabilization (the 1st-2d periods of the mature age), involutions of the nerve connections are defined in the splenic artery. The amount of the MF predominates in the nerves of the initial part of the plexus comparing to its terminal part. There is a direct correlative dependence between the amount of the MF in the plexus nerves and the size of the lumen in the splenic artery. Changes in the amount of the MF of different classes reflects qualitative differences of the splenic innervation relations at certain stages of the human postnatal development.     

Quantitative analysis of the density and pattern of adrenergic innervation of blood vessels

Summary Automated quantitative image analysis (QIAF) was used to measure and compare the adrenergic nerve plexuses of 4 blood vessels from the guinea pig, demonstrated by glyoxylic acid fluorescence (GAF). The results showed considerable quantitative variation of plexus density, size of bundles, and numbers of varicosities. A range of alternative procedural and anatomical sources of variability were investigated and assessed. The carotid artery was found to have a dense plexus with more nerves than that of the mesenteric artery; the mesenteric vein and abdominal aorta had sparse plexuses. The carotid artery plexus, despite the density of its nerves, possessed only half the number of varicosities of the mesenteric artery plexus. This sparse varicosity population was shown to have a similar density to the varicosities demonstrated by QIAF in the scattered nerves of the mesenteric vein and abdominal aorta. QIAF confirmed visual estimates of adrenergic plexus density, and was able to demonstrate less obvious differences of nerve density and size, and varicosity populations, between the different plexuses studied. The method is applicable to stretch preparations and transverse sections of many adrenergically innervated tissues.     

Adrenergic innervation of the arteries of different diameters in the human and animal pia mater

The adrenergic nervous plexuses of the pial arteries from 450- to 50 micron in diameter have been studied in dogs, cats and humans from 4 age groups (22-44 years, 55-64 years, 65-74 years and 75-86 years old). It has been found that the decrease in the vessel diameter was accompanied by a marked decline in the absolute number of nervous fibers in the nervous plexuses, however the concentration of the nerve fibers has not revealed any significant differences between human arteries from 450 to 100 micron in diameter and animal arteries from 300 to 80 micron in diameter. The number of varicosities-thickness along the nerve fiber--was the greatest in 200-100 micron human arteries and in 80-60 micron animal arteries. With ageing, the number of varicosities in the adrenergic nervous plexus of human pial vessels decreased faster than in the nerve fibers.     

Angiosomes of the brachial plexus: an anatomical study

This anatomical study analyzed the neurovascular relationships of the brachial plexus. Ten fresh cadaveric brachial plexuses were examined after injection of the arterial system. The vascular anatomical features of the brachial plexus were documented with microdissection after lead oxide/gelatin injection. The specimens were analyzed by using radiography (including digital subtraction techniques) and light-microscopic, macroscopic, and digital photography. Four angiosomes, based on the subclavian, axillary, vertebral, and dorsal scapular arteries, were observed. As noted in previous angiosome studies, connections between angiosome territories lay within tissues, in this case, nerve trunks. Nutrient vessels penetrated nerve trunks at points of branching within the brachial plexus, with a Y-shaped mode of division on entry. The vascular supply was markedly rich, often with true anastomotic connections occurring within the nerves. There was much variation in supply, depending on the vascular anatomical features of the subclavian artery.     

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.     

A histochemical study of the innervation of the cerebral blood vessels in the domestic fowl

Summary Adrenergic and cholinergic nerves innervating the cerebral arteries of the domestic fowl were examined by specific histochemical techniques.The adrenergic nerve plexuses of the cerebral carotid system are markedly denser than those of other vertebrates observed by similar techniques. They form longitudinally elongated meshworks of fine fibres in the vascular wall of the arterial branches. Those innervating the vertebro-basilar system are less dense and more elongated, and, as the size of the artery diminishes, the fibres of the plexus become coarser. In the small pial and parenchymal arteries they are reduced to a few fibres running parallel to, or spiralling around the vascular axis.The cholinergic nerve plexuses are not as dense as the adrenergic system. The acetylcholinesterase activity is very weak, except in the plexuses innervating the cerebral carotid artery and the proximal portion of the anterior and posterior rami. In the vertebro-basilar system, a few thick nerve bundles run alongside the blood vessels of the vertebral and basilar arteries. Cholinergic nerves enter the cranial cavity along the internal carotid, the vertebral and possibly the cerebro-ethmoidal arteries.Intracerebral capillaries and some arterioles are not innervated with cholinergic and adrenergic fibres of peripheral origin, but with ones arising from parenchymal nerve cells.     

Determination in the system of the neuromuscular relations of the coronary arteries at stages in human postnatal development

By means of micromorphometric method in transversal sections of electively stained right and left coronary arteries the data, characterizing the area of the middle and external sheaths, amount of myelin fibers in nerves, accompanying the artery have been obtained in men of 8 age groups (from birth up to old age), who died from causes not connected with the cardiovascular pathology. The summary amount of all classes of myelin fibers increases synchronously with an increase of the muscle sheath area from newborn up to 35-45 years of age. After this age the amount of the myelin fibers decreases together with decreasing area of the middle sheath. Minimal values of these indices are observed in the old age (85-90 years). The external sheath area increases permanently from birth up to the old age. The correlative analysis reveals a positive and significant connection of various degree between the myelin fibers number and value of the middle arterial sheath in persons of juvenile, mature and elderly age: amount of the muscular layer is adequate to the myelin fibers amount. In other age groups the correlative connections are either small, or not significant. Alternative, corresponding to each age quantitative gradations of the nervous connections are determined by means of the peripheral substrate. Its role in the vessels investigated is performed, to a definite degree, by the muscle sheath.     

The Brachial Plexus of the Sumatran Rhino (<Emphasis Type="Italic">Dicerorhinus sumatrensis</Emphasis>) and Application of Brachial Plexus Anatomy Toward Mammal Phylogeny

The peripheral nervous system is a promising resource for testing phylogeny although the branching patterns of peripheral nerves are not well documented outside of Homo sapiens. Here we describe the brachial plexus of the rare Sumatran rhinoceros (Dicerorhinus sumatrensis). We compare its brachial plexus to that of another perissodactyl (Equus asinus), an artiodactyl (Odocoileus virginianus), two carnivorans (Felis catus and Neovison vison), and one primate (Homo sapiens) and examine the phylogenetic structure of the resulting data. Brachial plexuses exhibit high rates of intraspecific polymorphism, but polymorphisms cannot be recognized from one specimen. To address concerns of error due to polymorphism, we dissected 52 mink brachial plexuses and compared them to human brachial plexus variation. Both species have numerous types of brachial plexus polymorphisms. Although most individual polymorphisms occur infrequently and unilaterally, because there are numerous types of polymorphisms, most humans and mink exhibit at least one polymorphism per brachial plexus. Parsimony analysis of 15 characters compiled from the brachial plexus data produced a tree that positions Artiodactyla and Perissodactyla as sister taxa, a result consistent with other analyses. Despite a high rate of polymorphism, the peripheral nervous system seems to carry a phylogenetic signal consistent with other morphological data. With a higher rate of taxon sampling, we suggest the brachial plexus will contribute valuable data for phylogenetic testing.     

Heart innervation after ligation of the left anterior descending coronary artery (LAD)

Distribution and amount of neuropeptide Y- and synaptophysin-immunoreactive nervous structures within the heart were investigated in dogs 4 days after ligation of the left anterior descending coronary artery (LAD). In the right atrium and posterior left ventricular regions, which were taken as (non-infarcted) control areas, neuropeptide Y-immunoreactive paravascular nerves and a perivascular nerve plexus running within the adventitia of the coronary arteries and their branches down to the arterioles were observed. Morphometric measurements of the area density revealed 0.099 +/- 0.014% for synaptophysin- and 0.037 +/- 0.0072% for neuropeptide Y-immunoreactivity within the posterior wall of the left ventricular myocardium. Four days after ligation of the LAD only single synaptophysin- and neuropeptide Y-immunoreactive nerve fibers were very rarely detected in the infarcted region of the anterior wall of the left ventricle. Above the ligature larger than normal neuropeptide Y-immunoreactive axons within nerves along the LAD indicated a blockage of the axoplasmic transport of this peptide. When investigating this model of experimental myocardial infarction, mechanical traumatization of peri- and paravascular nerves of the LAD by the ligature has to be considered as a major pathogenetic factor, in addition to ischemia leading to denervation of infarcted as well as non-ischemic myocardium.     

The brachial plexus in the chacma baboon (Papio ursinus)

Abstract: The brachial plexus in each of ten embalmed, mature chacma baboons was dissected to document the structure and branching pattern of this nerve plexus in this increasingly used research animal. In general, the brachial plexus in the chacma baboon was similar to the plexuses in the vervet and other Old World monkeys. However, several aspects were comparable to those observed in domestic animals. Thus the bipedal and quadrupedal abilities of the chacma baboon were reflected in the structure of its brachial plexus.     

An investigation of an autonomic innervation of the vertebral artery using monoamine histofluorescence

Blood flow to the hindbrain, via the paired vertebral arteries, must be uncompromised for adequate neurological functioning of its vital centres. Therefore, it would seem unlikely that the intracranial vertebral artery would need to vasoconstrict, thus reducing its blood flow. In order to investigate the existence and location of a noradrenaline-mediated constrictor mechanism in the wall of the intracranial vertebral artery, transverse sections of ten baboon and ten monkey vessels were stained with sucrose-potassium phosphate-glyoxylic acid (counterstained with malachite-green). This method allows the visualisation of catecholaminergic nerves when the sections are exposed to ultraviolet light. In this study of primate vascular tissue, however, none of the monkey or baboon vertebral artery sections showed the presence of noradrenergic nerves in the tunica media - tunica adventitia junction or penetrating the tunica media of the arteries. These findings indicate that the intracranial vertebral artery does not have a neurogenic vasomotor function in primates.     

Surface of the vascular plexuses of human cerebral ventricles

The racemose part of vascular plexuses of the lateral ventricles has been studied in fetuses and persons at various age in the scanning and transmissive electron microscopes. In the magistral arteries of the vascular plexuses the neural trunks have been studied. They form the periadventitial plexus with a more complex network of connections in mature persons. The sulci and the elongated folds between them make the relief of the plexus. A rough surface of epitheliocytes has deep craters and irregular protrusions, microvilli, cilia and spherical bodies. The epitheliocytes are arranged in a single layer and connected with each other by means of protoplasmic peduncles. Over the epithelial layer, as single groups, Kolmer cells are situated.     

Studies on intra-arterial cushions. IV. Perivascular nerve plexuses of ramifying arteries with intraluminal cushions at the branching points

Periarterial nerve plexuses were studied at branching points of arteries with intraluminal cushions. Serial sections were prepared from mouse kidney, pancreas and tongue, and studied by means of catecholamine fluorescence and staining for acetylcholinesterase. The periarterial nerve plexuses did not show any peculiarities at the branching points. The intraluminal cushions, as well as the tunica media of both the parent trunk and the collateral branches, were found to be free of vegetative nerves. It is concluded that the shape of intra-arterial cushions is passively altered, following the alterations of vascular geometry, and not in response to direct nervous stimulation.     

Avian enteric nerve plexuses

Summary The enteric nerve plexuses of the domestic fowl (Gallus domesticus) were investigated in sections and stretch preparations by means of the cholinesterase and glyoxylic acid fluorescence histochemical techniques. Cholinesterase-positive and varicose and non-varicose fluorescent nerve fibres were distributed at all levels of the gut in myenteric, submucosal, muscle and mucosal plexuses, and in a perivascular plexus. The density of the innervation and the detailed distribution of the nerves varied in different parts of the intestinal tract. All nerve plexuses appeared to be best developed in the rectum. Whereas the circular muscle coat contained a substantial number of nerves at all levels of the gut, the longitudinal coat was well innervated only in the rectum. The major portion of the mucosal plexus appeared to be associated with the intestinal glands. The nerve cell bodies were restricted to the myenteric and submucosal plexuses and were mainly cholinesterase-positive. Fluorescent ganglion cells were not observed. Pretreatment of stretch preparations with NADH: Nitro BT to stain ganglion cells showed that the majority of the cells were surrounded by a meshwork of fluorescent varicose fibres, although none of the fibres appeared to be associated with individual cells. The perivascular plexus was mainly associated with the arteries. The functional significance of the innervation is discussed.We would like to thank the British Council for financial support for Mr. H.A. Ali     

Heart innervation after ligation of the left anterior descending coronary artery (LAD)

Summary Distribution and amount of neuropeptide Y- and synaptophysin-immunoreactive nervous structures within the heart were investigated in dogs 4 days after ligation of the left anterior descending coronary artery (LAD). In the right atrium and posterior left ventricular regions, which were taken as (non-infarcted) control areas, neuropeptide Y-immunoreactive paravascular nerves and a perivascular nerve plexus running within the adventitia of the coronary arteries and their branches down to the arterioles were observed. Morphometric measurements of the area density revealed 0.099±0.014% for synaptophysin- and 0.037±0.0072% for neuropeptide Y-immunoreactivity within the posterior wall of the left ventricular myocardium. Four days after ligation of the LAD only single synaptophysin-and neuropeptide Y-immunoreactive nerve fibers were very rarely detected in the infarcted region of the anterior wall of the left ventricle. Above the ligature larger than normal neuropeptide Y-immunoreactive axons within nerves along the LAD indicated a blockage of the axoplasmic transport of this peptide.When investigating this model of experimental myocardial infarction, mechanical traumatization of peri- and paravascular nerves of the LAD by the ligature has to be considered as a major pathogenetic factor, in addition to ischemia leading to denervation of infarcted as well as nonischemic myocardium.This study was supported by the SFB 320 within the Deutsche Forschungsgemeinschaft (DFG)Parts of the results were presented at the 59. Scientific Session of the American Heart Association (1986) and at the Congress of the Deutsche Gesellschaft für Herz- und Kreislaufforschung 1987.     

Comparative study of the cholinergic and adrenergic innervation of the cerebral vessels in humans and various laboratory animals

Choline- and adrenergic innervation of intracerebral branches of the middle and posterior cerebral arteries has been investigated histochemically and electron microscopically in slices, or after their preparation after W. Penfield. The vessels have been studied in the area of the fields 41, 17 of the cerebrum, trunk and spinal cord of the human being, cat and dog. When studying innervation of the intracerebral arteries (ICA), the preparation method has some advantages in comparison with investigation of these vessels in slices of the brain. Around most of the ICA from 200 up to 30 mcm in the diameter choline- and adrenergic nervous conductors are revealed. Using the method for calculating varicosities in nervous plexuses, it is demonstrated that degree of the ICA innervation is two times less than that in the arteries of similar caliber in the cerebral pia mater.     

金丝猴属(RHINOPITHECUS)脊神经丛的组成

在灵长类中,脊神经丛通常分为颈丛、臂丛和腰骶丛,均出脊神经的腹侧支组成。各神经丛的组成似随种类不同而存在明显的差异,它直接反映了肌肉的起源和演化进程。灵长类在演化过程中,经历了树栖、地栖和直立生活三个阶梯。由于运动方式不同,肌肉也发生了相应的变化。树栖攀缘生活促使了上肢肌特别是肩带肌的飞跃发展,而支配这些肌肉的一些神经也发展成为单独的神经。随着手肌的分化逐步完善,支配手肌的一些神经最后发展成单独的,而且是臂丛中最粗的神经。所以,深入研究猿猴类各神经丛演化的全貌,对于探索灵长类的进化,尤其是猿类如何实现手足分工和手的解放,最后演化为人类这一理论将提供具体资料。     

The origin and distribution of adrenergic nerve fibres in the guinea-pig colon

Summary A detailed study of the origin and distribution of sympathetic fibres in the distal colon of the guinea-pig has been made using the fluorescent histochemical method for localizing catecholamines. The extrinsic adrenergic fibres of the colonie sympathetic nerves follow the inferior mesenteric artery and its branches to the colon. Some of the extrinsic adrenergic fibres are associated with the parasympathetic fibres of the pelvic nerves near the colon. Complete adrenergic denervation follows the removal of the inferior mesenteric ganglion or the destruction of the nerves running with the inferior mesenteric artery.No fluorescent fibres, other than those associated with blood vessels, were observed in air-dried stretch preparations of the isolated longitudinal muscle. However, a substantial number of varicose, terminal fibres, not associated with blood vessels, were observed in the circular muscle. Some varicose fibres, apart from those associated with ganglion cells, were observed in the myenteric plexus. These fibres were seen in the bundles of nerves running between the nodes of the plexus and also as single fibres which branched from the plexus to end in areas free of ganglion cells.Three plexuses of adrenergic nerve fibres have been distinguished in the submucosa: a dense plexus of terminal fibres innervating both the veins and arteries; a plexus consisting of innervated nodes of ganglion cells, connected by bundles of fluorescent and non-fluorescent nerves; and a plexus of varicose and non-varicose fibres, which is not associated with ganglion cells. Some groups of ganglion cells in the submucosa were without adrenergic innervation.A plexus of varicose fibres forms a meshwork in the lamina propria of the mucosa. The muscularis mucosae is sparsely innervated. Most of the blood vessels in the mucosa are not associated with adrenergic fibres.