Pathomorphology of the nodose ganglia of the vagus nerves in burns

Pathomorphology of ganglion nodosum was studied by means of neurohistological methods in 65 dead patients during different periods of burn disease and demonstrated a definite dynamic of structural modifications. In period of burn shock there were discovered dystrophic changes and necrosis of neuron separate groups, varicose thickness of a myelin sheath, in period of toxemia hypertrophied neurons with thick axons predominated, in period of septic toxemia and burn exhaustion predominated atrophic changes, necrotic neurons and grain-blockage disintegration of nervous fibres.     

Pathomorphology of stellate ganglia in thermal injuries of the body

Structural changes of stellate-ganglia in 80 patients aged from 20 to 80 dead in different stages of burn disease (shock, toxemia, septico-toxemia and burn exhaustion) were studied with neurohistological and neurohistochemical methods. It was determined that the increasing of neuron's reactivity was the sign of its changes at the early stages of burn disease. Later hypertrophy, atrophy and neuron's body destruction took place. At the period of burn shock excessively bright luminescence sympathetic neurons prevailed, at the period of toxemia its number decreased. At the period of toxemia and septico-toxemia for the first time it was determined the increase of lipofuscin insertion in adrenergic neurons as well as the increase of the activity not only at the shock period but also at the next periods of burn disease.     

Changes in the cell pool of the intramural neural plexus of the large intestine during postnatal development

Using a complex of morphological, morphometrical and histochemical methods, morphofunctional regularities for the age-related changes in the cell pool of intramural (myenteric and submucosal) nervous plexuses have been studied in the large intestine of albino rats during postnatal development. Three periods in development and differentiation of neurocellular resources of the intestine have been distinguished: progressive growth, relative stabilization and regressive phenomena. Peculiarities in structural-chemical transformation of cellular elements have been revealed during each period. Reduction of the cell pool of plexuses, as well as development of adaptive compensatory processes take place with ageing. The role of denervation of the organ in development of age-related functional disorders is discussed.     

Inter-organ neural communications in the innervation of bronchi and pulmonary circulation vessels

By means of V.P. Vorobiov's preparation in complex of the thoracic cavity organs of persons at various age and sex in fetuses, sources of innervation of bronchi and vessels of the pulmonary circulation have been stated. They make the composition of the cardiac nerves getting off the superior, middle cervical, cervico-thoracic (stellate) and from 3 to 5 thoracic nodes of the sympathetic trunk, superior and inferior cardiac branches of the nervus vagus. Connection between the nerves of the bronchi and vessels of the pulmonary circulation with the cardiac and esophageal nerves and formation of interorganic nervous plexuses are demonstrated. Not always the diaphragmal nerve participates in the innervation of the bronchi and pulmonary vessels. In total preparations and flat sections, elective revealing of the nervous elements with Shiff reagent in M. G. Shubich and A. B. Khodos modification and Gomori thiocholine method, makes it possible to follow connections of the pulmonary veins nerves with the left atrium, intrapulmonary connection of the perivascular and peribronchial plexuses, as well as participation of nervous elements of the pulmonary trunk in innervation of the right ventricle walls. There are multiple vegetative communications participating in innervation of the bronchi and vessels of the pulmonary circulation. The relations of the pulmonary nerves with the nerves of other thoracic organs are very complex; this explains the nature of the repercussive reactions of the lungs after surgical interventions performed in the other organs of the thoracic cavity.     

Adrenergic and cholinergic innervation of the prostate in laboratory animals

The prostate innervation has been studied in 50 white rats, 12 rabbits, 12 guinea pigs, 6 cats and 6 dogs. Together with the impregnation techniques, Karnovsky-Roots method has been applied, for revealing cholinergic components, and the incubation method in 2% solution of glyoxylic acid, for revealing adrenergic nervous structures. Density of adrenergic and cholinergic nervous plexuses has been estimated by means of the planimetric point method. The prostate of the laboratory animals possesses well manifested adrenergic and cholinergic nervous plexuses. The organ's alveolus and ducts are covered with adrenergic and cholinergic fibers, however, the relative density of the cholinergic plexuses is less than that of the adrenergic ones. The guinea pig prostate is the most richly supplied with the adrenergic nervous plexuses, and the rabbit prostate--with the cholinergic nervous plexuses.     

Blood supply of the trachea and bronchi in the rat

Existence of longitudinal and circular arterio-arterial anastomoses are stated, as well as various ways of outflow from the veins of the organs studied; this demonstrates essential compensatory abilities of this bed in blood supply regulation and draining at inflow and outflow from the microcirculatory system bed. Different topography of the arterial sources, venous plexuses, capillary fields allows to suppose different histophysiology of the tracheal zones mentioned: the anterior (laryngotracheal), middle and posterior (bifurcational). For the tracheal microcirculatory bed, metamerically repeated microcirculatory areas are peculiar. Distribution of the bronchial arteries takes place up to the terminal bronchi. In the area of the latter, anastomoses of the bronchial vessels with the pulmonary artery are observed.     

Neural connections of the heart and superior vena cava in the rabbit and man

Innervational connections of the heart and the superior vena cava wall have been studied in the rabbit and the man. Besides, series of their embryos, impregnated with silver salts after Cajal-Favorsky have been investigated. Methods of Bielschowsky-Gros, Gomori and Karnovsky-Roots have also been applied. Adrenergic nervous elements have been revealed by means of incubation the slices in 2% solution of glyoxylic acid. Abundant cholinergic and adrenergic nervous plexuses are revealed on the wall of the superior vena cava, they are tightly connected with corresponding plexuses of the heart. Developmental of these nervous connections is followed, when embryogenesis of the cardiac nervous plexuses and large major vessels is studied in serial sections of embryos and fetuses of the rabbit and the man.     

Development of the neural and tissue components of the excretory ducts of the liver, pancreas and Odd's sphincter in human embryogeny]

The development of pancreatic, hepatic, cystic, common bile ducts, the Oddi's sphincter and their nervous apparatus were studied during prenatal human ontogenesis of fetuses and newborns. The process of formation of the nervous apparatus corresponds to the development of tissue structures of the ducts and the sphincter. The distinctions in the organization of nervous elements which are noted in adult humans are laid in the process of embryogenesis. These distinctions are especially pronounced in the structure of nervous plexuses and receptory endings. The nervous apparatus of the Oddi's sphincter region has a complex arrangement. This is the site of concentration of nerve nodules and receptory endings as well as abundant nervous connections between plexuses of the pancreatic head, duodenum and orifice zones of the both ducts. The receptors in nerve nodules and pericellular apparatuses on the bodies of ganglionic neurons were revealed.     

Adrenergic innervation of the myocardium and skeletal musculature of the rabbit exposed to vibration

Innervation of the myocardium and that of foreleg musculature has been studied in rabbits subjected to the local vibration effect. The point where the vibration is applied is the foreleg, because its nerve plexuses are in the tightest way connected with the cardiac nervous apparatus. For treatment of the sections incubation in 2% solution of glyoxylic acid is used, which is followed with luminescent microscopy. While studying adrenergic nerve plexuses of the right auricle, their luminescent activity is stated to decrease more than by a half. In the ventricles only single perivascular adrenergic nerve plexuses remain. A constant reaction of the plexuses mentioned is revealed not only in the right, but in the left extremity subjected to a direct vibration. Taking into account that the vibrational effect is performed as a generalized action and it embraces the whole skeleton of the animal, it is possible to suggest that the activity of the sympathetic nervous plexuses results in a constant influence of noradrenaline on the wall of blood vessels producing their steady spasmodicity.     

Adrenergic innervation of the kidneys in man and various laboratory animals

By means of the neurohistochemical method for slice incubation in 2% solution of glyoxylic acid, innervation of the kidneys of a 57-year-old man after a sudden cardiac death has been investigated, as well as innervation of the kidneys in white rat, rabbit, guinea pig and cat. A rich adrenergic innervation in the organ's blood vessels has been revealed. In particular, adrenergic nervous fibers have been found along the course of afferent glomerular arterioles. Together with innervation of the proximal and distal convoluted tubules, a high density of the terminal adrenergic nervous plexus is revealed along the course of the nephron loops. Adrenergic nervous plexuses of high density are found in the area of the initial part of the urinary excretory pathways and their connection with nervous plexuses of the kidney itself.     

Toxicity and proteolysis in gnotobiotic rats with thermal burns]

Experiments were conducted on germ-free (gnotobiotic) rats. A study was made of the toxic properties of the organs and the activity of proteolytic enzymes in them after thermal burns. Despite the absence of pathogenic microbial flora the germ-free rats developed the state of toxemia with an increase of the level of proteolytic enzymes. The extent of the toxic and catabolic reaction depended on the severity of the burn. Intoxication and an increase in proteolysis in the gnotobiotic rats were similar, and, in a number of cases greater than in usual animals. A conclusion was drawn on the important role of the tissue sources of intoxication in burns. A correlation between the toxemia and proteolysis was established.     

Distribution of neurons with high-affinity uptake sites for GABA in the myenteric plexus of the guinea-pig,rat and chicken

The occurrence of neurons possessing high-affinity uptake sites for GABA was studied in the myenteric plexus of the guinea-pig ileum, caecum, and proximal and distal colon, the rat proximal colon, and the chicken gizzard with the use of 3H-GABA and autoradiography. Experiments were carried out on plexuses that had been freshly isolated from the gut wall or on isolated plexuses that had been maintained as explant cultures for 7 to 14 days. Scattered neurons selectively labelled with 3H-GABA were found in the myenteric plexuses from all the areas examined. The results suggest that GABAergic neurons are widely distributed in the enteric nervous system.     

Intrinsic Innervation of the Chicken Lower Digestive Tract

We have studied the different components of the enteric nervous system in the rectum and cloaca of the chicken by means of hystochemical and immunohistochemical techniques. We found cholinergic neuronal bodies as well as nervous fibers, which constitute part of the Meissner and Auerbach plexuses. We also observed plentiful catecholaminergic fibers in both plexuses, though there were no catecholaminergic neuronal bodies. With respect to the Vasoactive Intestinal Peptide (VIP) and substance P (SP) positive peptidergic innervation, only positive fibers were found, which were less abundant than in the other zones of the gastrointestinal tract. The optic microscopy results were confirmed by electron microscopy.     

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.     

Vital microscopy and histochemical study of the autonomic nervous system of the small intestine in animals with thermal burns

By means of vital microscopy a possibility of histochemical detection of redox enzymes and of study of changes in their activity in intramural nerve plexuses of the small intestine on a live animal was demonstrated. Severe thermal trauma induced a disturbance of permeability of mitochondrial membranes of the Auerbach's plexus nerve cells; as a result, there was a change in the activity of redox enzymes localized within the mitochondria. Lumbar novocain block performed soon after the burn trauma normalized the state of the mitochondrial membranes of the nerve cells.     

Nervous control of intestinal fluid transport: physiology and pathophysiology

1. The enteric nervous system (10(8) neurones in man) consists of the myentric plexus, the submucosal plexus and other minor plexuses. Eighteen different chemicals are candidates for the role of neurotransmitters in the ENS. 2. The ENS together with the autonomic nervous system and the hormonal system controls gut epithelial transport systems.     

Ultrastructural characteristics of anterior gut innervation of Gallus gallus

The enteric nervous system of the bird's anterior gut is very well developed. Myelin fibres are seen accompanying the nervous trunks up to the mucous layer. Glial cells duplicate the number of neurons in the myenteric plexuses. Their number decreases at the submucous plexuses, but it is always higher than the neurons. Isolated neurons are widely spread in the circular muscle coat accompanying the nervous trunks which can be inter and intrafascicularly located. Direct synaptic contacts with the soma neuronal membranes are very often seen. We have never observed synaptic specializations. The most prominent varicosities either in the peripheric nervous trunk axons or directly laying on the soma membranes are those containing peptidergic or mixed vesicles of cholinergic and peptidergic types. The neurons show big nuclei of different size and shape. Neighbouring smooth muscle cells show abundant caveolae near the nervous elements. Although we have not observed close contacts with glands, thin axon bundles spread near the glandular cells of the mucous layer.     

Neurophysiology of Ganglia of Auerbach's Plexus

The enteric plexuses of the automatic nervous system may beconsidered, on the basis of both function and morphology, tobe a simple integrative nervous system of vertebrate animals.Microelectrcde studies of single unit activity within entericganglia reveal four distinct types of ganglion cells distinguishedon the basis of pattern of spike discharge. These are (i) burst-typeunits which spontaneously discharge bursts of spikes at periodicintervals; (ii) fast- and slowly-adapting mechanoreceptors;(iii) tonic-type units which respond to mechanical stimulationwith prolonged, all-or-nothing trains of spikes; (iv) single-spikeunits which spontaneously discharge single action potentialsat variable intervals. The enteric plexuses are adapted forcontrol of the intestinal musculature which behaves as an electricalsyncytium activated by myogenic pacemaker potentials. The mechanismof neural control is integration of continuous neurogenic inhibitionof the inherently excitable musculature.     

Neuronal plasticity of the enteric nervous system is correlated with chagasic megacolon development

Chagas' disease is one of the few functional gastrointestinal disorders for which a causative agent has been identified. However, some pathological aspects of the chagasic megasyndromes are still incompletely understood. Chagasic megacolon is characterized by an inflammatory process, organ dilatation and neuronal reduction in both plexuses of the enteric nervous system (ENS). Although some studies on the ENS in Chagas' disease have been performed, the process of neuronal destruction and neuronal regeneration still remains unclear. Our hypothesis is that the regeneration process of the ENS may be involved with the mechanisms that prevent or retard organ dilatation and chagasic megacolon development. For that reason, we evaluated the neuronal regeneration with the marker GAP-43 in the colon's neuronal plexuses from chagasic patients with megacolon, and from non-infected individuals. Visual examination and quantitative analysis revealed an increased neuronal regeneration process in the dilated portion from chagasic patients when compared with the non-dilated portion and with non-infected individuals. We believe that this increased regeneration can be interpreted as an accentuated neuronal plasticity that may be a response of the ENS to avoid megacolon propagation to the entire organ and maintain the colon functional innervation.     

Cholinergic, nitrergic and peptidergic (Substance P- and CGRP-utilizing) innervation of the horse intestine. A histochemical and immunohistochemical study

The small and large intestine of adult horses were histochemically and immunohistochemically investigated in order to evidence components of the intramural nervous system. The general structural organization of the intramural nervous system was examined by using Nissl-thionin staining as well as the anti-neurofilament 200 (NF200) immunoreaction, which demonstrated the presence of neurons in the submucous as well as myenteric plexuses. The additional presence of subserosal ganglia was shown in the large intestine. Acetylcholinesterase (AChEase) activity was observed in both the submucous and myenteric plexuses. Localization of acetylcholine-utilizing neurons was also evidenced by immunohistochemical reactions for choline acetyltransferase (ChAT) and vesicular acetylcholine transporter (VAChT). With both histochemistry and immunohistochemistry possible cholinergic nerve fibres were detected in the inner musculature. The two possible cholinergic co-mediators Calcitonin Gene-Related Peptide (CGRP) and Substance P (SP) have been investigated by an immunohistochemical approach. CGRP immunoreactivity was detected in roundish nerve cell bodies as well as in nerve fibres of the submucous plexus, whereas SP immunoreactivity was evidenced in nerve fibres of the tunica mucosa, in nerve cell bodies and fibres of the submucous plexus and in nerve fibres of the myenteric plexus. NADPH-diaphorase reactivity, which is linked to the synthesis and release of nitric oxide, was detected in nerve cell bodies and nerve fibres of both the submucous and myenteric plexuses as well as in a subserosal localization of the large intestine. The nitrergic components were confirmed by the anti-NOS (nitric oxide synthase) immunoreaction. Results are compared with those of other mammals and related to the complex intestinal horse physiology and pathophysiology.