[Pathological changes in the nervous structures of the aortic wall tissue adjacent to an unstable atherosclerotic plaque]. / Patologicheskie izmeneniya nervnykh struktur v tkanyakh stenki aorty, prilezhashchikh k nestabil'noi ateroskleroticheskoi blyashke.

OBJECTIVE: To study of nerve structures in the aortic wall in atherosclerosis using a complex of immunohistochemical markers. MATERIAL AND METHODS: The objects of the study were excised fragments of the wall of the thoracic and abdominal aorta along with visually determined unstable atherosclerotic plaques. To study nerve structures on paraffin sections, immunohistochemical reactions were performed for the PGP 9.5 protein, tyrosine hydroxylase, and synaptophysin. RESULTS: It has been established that pronounced pathological changes are observed in the nervous structures of the aortic wall near unstable atherosclerotic plaques. Reactive, dystrophic, and severe degenerative changes in neurocytes, nerve fibers, and glial cells are described in the elements of the nervous apparatus of the adventitia (microganglia, nerve trunks, and nerve plexuses). It was found that only sympathetic neurons and their postganglionic fibers remain in the intramural ganglia, while the structures of the parasympathetic nervous apparatus undergo degeneration. Destruction of perivascular nerve plexuses and vasa vasorum in the adventitia, as well as degeneration of varicose axons of the main terminal synaptic plexus at the border of adventitia and superficial smooth muscle layer of the media were demonstrated. CONCLUSION: It is assumed that the presence of inflammatory infiltrates in the adventitia and intima, denervation and death of vasa vasorum can serve as factors determining the development of the atherosclerotic process.

[Features of innervation of epicardial adipose tissue in rats during aging (immunohistochemical study).]

The purpose of the article is to study the structure, innervation and state of the epicardial adipose tissue of the aortic-pulmonary region of the heart of rats at the age of 3-4 months and 18-23 months using neuroimmunohistochemical markers. Using a complex of histological and immunohistochemical methods, various nervous apparatus (ganglia, clusters of chromaffin cells, nerve trunks, nerve fibers, nerve plexuses, synaptic endings) with different mediators were identified in the white and brown adipose tissue of the base of the rat heart. It was found that parasympathetic and sympathetic postganglionic nerve fibers are involved in the innervation of white and brown adipose tissue. They penetrate into adipose tissue as part of Remak's cords of varicose axons along arterial vessels, form terminal synaptic plexuses of the en passant type, and are involved in the innervation of adipocytes of both types of epicardial adipose tissue. It was found that PGP 9.5+ cholinergic terminal nerve fibers predominate over catecholaminergic ones. During aging of rats, neurodegenerative, involutive (desimatization), and destructive pathological changes in white adipocytes were noted in epicardial adipose tissue.

[Morphological signs of neurogenic inflammation in the heart of rats during aging.]

Using histological methods of staining with toluidine blue, hematoxylin-eosin and immunohistochemical reactions for the PGP 9,5 protein, tyrosine hydroxylase (TH), Iba-1 protein, cellular changes in different parts of the heart of Wistar rats at the age of 18-23 months were studied. In the connective tissue of the heart base, focal inflammatory infiltrates were found, near which PGP 9.5+ and TH+ plexuses, consisting of parasympathetic and sympathetic nerve fibers, were detected. In the area of the valvular heart apparatus, at the border of the anneau fibreux and the myocardium of the right atrium, pathological changes in nerve structures were found: degeneration of nerve fibers and granular destruction varicose axons of the terminal plexus. A close relationship has been established between axons of the terminal nervous network and cells of inflammatory infiltrates and blood capillaries. The features of the localization of neurocellular inflammatory complexes consisting of nerve fibers, blood capillaries and cells participating in the local inflammatory process (mast cells, histiocytes, monocytes, fibroblasts, plasma cells) in various parts of the myocardium in old animals are described. The chronic nature of neurogenic inflammation in the heart during aging has been established.

[Structural and functional changes of endothelium of heart's vessels of old rats according to immunistochemical studies.]

The aim of the work is to investigate the morphofunctional changes of the vascular endothelium in different parts of the heart of aging rats using immunohistochemical detection of Willebrand factor. Reactive, dystrophic and pathological changes of endotheliocytes in different parts of the heart of old (18-23 months) rats were first identified using an immunohistochemical marker vWF. They are most expressed in the endothelium of the arterial vessels of the aortic root, coronary arteries of the epicardium, and myocardial capillaries. In this work, desquamation of endothelial cells into the blood, death of capillaries in the myocardium, an increase in the number of sinusoidal vessels, their mummification, the formation of lacunae or cisterns filled with blood were found. It has been established that the secretory activity of endotheliocytes increases with aging. It is established that the products of protein metabolism, pigment, Weibel-Palade body and various sizes of blood clots accumulate in the cavity subaroundal cone of heart in old rats. Pigment structures were also found in the valves and the fibrous ring. The data obtained are of great diagnostic value.

[Features of chronic pancreatitis pathomorphism in the validity of surgical approaches].

The results of examination and surgical treatment of 298 patients with chronic pancreatitis and the original morphological investigations of material of the pancreas were studied. The data allowed the detection of additional criteria features of inclusion of the patients with chronic pancreatitis to be made in groups according to foreign Marseilles-Roman classification (1988). It is shown, that the basis of study of morphogenesis of chronic pancreatitis is immunohistochemical method, which let the authors diagnose not only the pathological changes of exo- and endocrine sections of pancreas, but at the same time the structural features of nervous apparatus and vessels of microcircular bed. The revealed morphological features of different forms of chronic pancreatitis vs clinical finding characteristics and the data of instrumental and laboratory methods of research allow the substantiation of surgical treatment version to be made.

[Efferent innervation of pulmonary blood vessels and bronchi in rat (an immunohistochemical study)].

In this investigation the peculiarities of innervation of bronchi and blood vessels of the lung were studied in 20 rats using immunohistochemical demonstration of synaptophysin and alpha-actin. The results obtained have showen that the densest innervation is typical for bronchial walls, particularly, for the muscular lamina. Synaptophysin-immunoreactive terminals (SFIT) were detected in the bronchi in close association with both circular bundles of smooth muscle cells and microganglia. Dense network of SFIT was found in the pulmonary vein--in its middle tunic formed by cardiomyocytes. In contrast to the bronchi and pulmonary vein, large branches of the pulmonary artery contained no SFIT. We briefly discuss the problem of the origin of the nerve fibers described and their functions and suggest that SFIT are formed by efferent fibers (axons) of neurons arising from either the intrapulmonary parasympathetic ganglia.

[The immunomorphologic analysis of innervation of chromaffin paraganglian cells of the mammalian arteries and heart].

Innervation of chromaffin cells of paraganglia of the wall of mammalian large arterial vessels and heart (in rat, cat, and human) was studied by neuromorphological and immunohistochemical methods. There is established similarity in structure of specialized, "basket"-type nerve endings of the chromaffin cells (ChC) with pericellular nerve apparatuses of sympathetic and parasympathetic autonomic neurons. It is proposed to use immunohistochemical reaction for synaptophysin as method of selective detection of ChC of paraganglia and adrenal medulla. The conclusion is made that synaptophysin-positive terminals (SPPT) found on bodies of ChC and postganglionic neurons represent efferent, rather than afferent, synapses formed by myelinated axons of preganglionic fibers. It is suggested that ChC of paraganglia alongside with their characteristic endocrine function participate in complex mechanisms of chemoreceptor regulation of tissue homeostasis of mammalian blood vessels and heart.

[Distribution and structural organization of autonomic neural apparatus of the rat pancreas (an immunohistochemical study)].

Using the immunohistochemical methods for detection of neurofilaments (NF), peripherin (PRF), synaptophysin (SF), tyrosine hydroxylase (TH) and Nissl-staining with toluidine blue, thick sections (10-20 microm) prepared through all parts of pancreas of adult Wistar rats (n=7) were studied. The topography and the density of distribution of pancreatic islets in the various parts of pancreas were defined. The greatest density of the islets was found in the body of pancreas. The dense innervation of the organ was detected which included several nervous plexuses: the big-looped one consisting of nervous bundles and small trunks of NF-positive myelinated and unmyelinated nervous fibers, the second one was formed by PRF-positive thin posganglionic bundles of axons and microganglia, and the third one, detected with SF-staining, was main terminal plexus consisting of varicose axons with en passant synapses. Interactions of synaptophysin-positive terminals (distant en passant synapses) with blood vessels, endocrine (islet) and exocrine cells, excretory ducts of the pancreatic lobules are described in details. Peculiarities of the structure of parasympathetic ganglia, their neurons, and pericellular synaptic apparatus are described; problems of the innervation and the nature of pancreatic insular endocrine cells are discussed. Attention is drawn to the fact that in no case neurons were found in the islets in the rat pancreas.

[Innervation of cardiac muscle tissue in rat pulmonary veins].

The pulmonary vein (PV) of 16 adult male Wistar rat was studied using synaptophysin immunohistochemistry and staining with toluidine blue and hematoxylin. Its intrapulmonary trunk wall was found to have a unique structure. The middle tunic contained cross-striated muscle tissue that was identical to the cardiac muscle tissue in posterior wall of the myocardial atrium. The thickness of the muscular tunic increased with the increase of vein diameter. The thickest layer of cardiac muscle fibers was located in the orifice of the main trunk, and the thinnest - in the lateral veins (50-100 microm in diameter), carrying the arterial blood from the respiratory portion of pulmonary lobe. Along their whole length, cardiac muscle fibers are densely innervated. Efferent synaptophysin-positive endings of the terminal plexus were found to be tightly associated with cardiac muscle fibers, capillaries of the media in the area of PV orifice and vasa vasorum of the adventitia.

[Glial reaction in the forebrain subventricular zone in the rat model of Alzheimer's disease].

The purpose of this study was to investigate the long-term reactive changes in the subventricular zone (SVZ) of the rat brain lateral ventricles after the intraventricular injection of beta-amyloid peptide (BAP). It was found that 3 months after BAP injection ependymal cells and SVZ cells reacted to the intraventricular BAP injection by the formation of glial structures, similar to amyloid plaques in their composition, cell structure and possible developmental mechanism. Using immunohistochemical methods, it was shown that they consisted mainly of reactive astrocytes and microgliocytes. It is suggested that atypical morphogenesis of these structures is associated with the interrelationship between the degenerative and regenerative processes, which involve both ependymal cells and forebrain proliferative zone progenitor cells.

[Heart innervation in rats (an immunohistochemical study)].

The aims of the present study were to investigate the structure of the nervous apparatus in different heart regions using the immunohistochemical methods. The study was performed in Wistar rats (n - 5). For selective staining of synaptic structures, synaptophysin (Syn) demonstration was used, while neurofilament proteins (NF-M) were used to detect axonal neurofilaments. The innervation apparatuses in the heart were shown to be unevenly distributed. High density of Syn- and of NF-M-positive axons was found in the myocardium near the atrial sinus, vena cava superior and inferior, pulmonary veins, aorta, truncus pulmonalis, as well as in the deep layers of atrial myocardium, and in the myocardium of anterior and posterior ventricle walls. In the heart apex, within the ventricular myocardium, the density of immunopositive axons was low. Using the antibodies against Syn, only the synaptic terminals of the efferent postganglionic nerve fibers and of the parasympathetic vegetative nerve fibers were selectively demonstrated in the heart, as well as the pericellular synapses on the parasympathetic neurons of intracardiac ganglia. NF-M-immunopositive axons, unlike Syn-positive terminals, were found not only in the myocardium, but also in the epicardium and the endocardium within the same regions of the heart. The authors believe that these axons belong to afferent sensory and efferent preganglionic myelinated nerve fibres of PNS.

[The area centralis of the mammalian retina: morphology and histogenesis].

This review summarises both classical and current literature data on the structure and the histogenesis of the retina of the mammalian eye and, in particular, of its specialized region--area centralis. The review describes the modem concepts of cytoarchitecture of area centralis, as well as the peculiarities of its blood supply, and presents the details of its histogenesis from early embryonic stages to postnatal development.

[The histogenesis of interrenal primordium of the adrenal gland in pig (Sus domestica)].

Using light, electron microscopy and cytochemistry, the early (embryonic week 4-8) stages of adrenal gland (AG) development were studied in domestic pig. The interrelations between the cells of the fetal cortex (FC) and chromaffin cells (CC) were traced. At week 5, AG primordium is represented by FC, which consists of the epithelioid cells, with the ingrowing neural cords containing CC islets. Starting at the early embryonic period and up to fetal period, CC and interrenal cells of FC are closely interrelated with each other and sinusoidal capillaries. Both cellular types are at different stages of differentiation, including the functionally active elements. At weeks 7-8, FC cells undergo involution, while those ones, left at periphery, form definitive cortex. CC are located in the central part of the organ and form suprarenal tissue. Authors hypothesize, that CC, migrating into AG primordium, initially induce the development of interrenal primordium, and later cause the involution of FC. This, possibly, may be explained by the fact that further antenatal and postnatal development of the organism requires more corticosteroids than the amount produced by FC.

Sensory innervation of the brain - myth or reality?

This article provides a critical analysis of the concepts of the sensory innervation of the brain and spinal cord presented in Sotnikov's articles in issues 2 and 3 of this volume. Criteria for the identification of intracerebral primary sensory neurons and the possible roles of neuronal cilia are discussed. The significance of asynaptic dendrites and bipolar cells is considered. The importance of the correct use of a variety of terms is emphasized, and the need for using combined morphological and electrophysiological analysis in investigating sensory intracerebral exteroceptors is noted.

[Sensory innervation of the brain--myth or reality?].

This paper contains a critical analysis of conceptions of the sensory innervation of the spinal cord and the brain, presented in the articles by O.S. Sotnikov (issues 2 and 3 of this journal). The criteria for identification of intracerebral primary sensory neurons are examined, as well as the possible role of neuronal cilia. The significance of asynaptic dendrites and bipolar cells is discussed. The importance of an adequate usage of some terms and the advisability of a combined morphological and physiological analysis for the study of sensory intracerebral exteroceptors is emphasized.

[Development of adrenal chromaffin tissue]. / Razvitie khromaffinnoi tkani nadpochechnika.

The purpose of the present investigation was to study the morphological peculiarities of chromaffinoblasts and to determine their interrelations with the surrounding cellular elements of the fetal cortex at the early stages (embryonic weeks 4-7) of their migration into the developing adrenal gland of a pig. At week 5 neuro-cellular cords, consisting of so-called "naked" axons, neuroblasts, lemmoblasts, undifferentiated cells, chromaffinoblast clusters and chromaffinocytes, grow into the fetal cortex from side of abdominal aorta. In fetal cortex parenchyma chromaffin elements form cords, lobes, "medullary globes", which are enveloped by a basal membrane, which is a derivative of satellitocytes. Chromaffinocytes are stained with Wood's stain, potassium bichromate and, judging by the presence of secretory granules in their cytoplasm, are capable to synthesize summary catecholamines and to release them into the blood at the early stages of development. "Medullary globes" are the centers of proliferation and differentiation of the chromaffin cells in the adrenal medulla. The problem of chromaffin tissue stem cells is discussed.

[The developmental characteristics of the embryonic anlagen of rat neocortex and spinal cord when transplanted into the distal end of the dissected sciatic nerve of adult animals]. / Osobennosti razvitiia émbrional'nykh zakladok neokorteksa i spinnogo mozga krys v usloviiakh transplantatsii v distal'nyi konets pererezannogo sedalishchnogo nerva vzroslykh zhivotnykh.

The spinal cord and cerebral cortex of 14 day old embryos of Wistar rats were transplanted into the distal stump of the adult rat cut sciatic nerve in order to study dynamics of the development of the transplanted cell elements, and to elucidate relations of neuronal elements in the central and peripheral nervous systems. By means of light and electron microscopy it has been stated that the transplanted nerve cells of the cortex and spinal cord could survive for 60 days and differentiate from neuroepithelial cells and neuroblasts up to young and mature neurons. In the transplants a neuropil is seen to form with both unmyelinated and myelinated axons and synaptic contacts. In the cortex transplants cavities appear paved with ependyma-like cells having cilia and microvilli. It has been found that axons of the transplanted spinal cord neurons may leave transplants to be myelinated by the recipient's Schwann cells of the peripheral nerve.