Morphologic mechanisms of blood flow regulation in the hemomicrocirculatory system of the human heart during ontogenesis

Hearts of 220 human corpses, who had not any cardiovascular system disease during their life, have been distributed into age groups, beginning from fetuses up to old age. By means of injection, silver nitrate impregnation and scanning electron microscopy methods, applied to corrosive preparations, morphological mechanisms of the blood stream regulation in the hemomicrocirculatory bed of the human heart have been revealed in ontogenesis. The first group of the regulation mechanisms includes proper mechanisms inherent in the links of the microbed: spatial orientation of microvessels, precapillary sphincters, anastomoses between these vessels, sequence in arrangement of the endothelial cell nuclei, length, diameter and number of links in the microcirculatory bed. The second group embraces those mechanisms, that depend on structure of the myocardial wall, influencing the microcirculatory bed.     

Organ and tissue-specific properties of the microcirculatory bed of the heart

The auricular and ventricular microcirculatory bed has been studied in persons of mature age, not suffering from any cardio-vascular diseases during their life. As a whole, 48 objects have been studied. The microcirculatory bed has been revealed in sections of the cardiac wall 70-100 mcm thick using silver nitrate impregnation after V. V. Kuprianov. Organ- and tissue-specific properties of the vascular microcirculatory bed are revealed in interrelations of the vessels and the structural elements of the cardiac wall (myocardium, and connective tissue structures), in position of nuclei of the endothelial cells of the capillary wall and in places of the capillary branchings. Principle differences in structure of the auricular and ventricular microcirculatory bed are demonstrated. The notion the organ- and tissue-specific properties of the microcirculatory bed vessels is discussed.     

Organizational features and morphometric characteristics of the hemomicrocirculatory bed of the human brain dura mater

By means of silver nitrate impregnation and hematoxylin -- eosin staining the microcirculatory bed of the human brain dura mater (the second half of the mature age) has been investigated. Owing to the analysis of the morphometrical data of module organization of the hemomicrocirculatory bed, an objective quantitative characteristics of its peculiarities in various layers and areas of the dura mater is presented. In three layers of the dura mater in the fornix and skull basis area, falx cerebri and tentorium cerebelli venular links predominate. Most of all morphometrical parameters of the venular vessels increase in the internal layer of the dura mater in the skull basis area. Conditions of functioning for the human brain dura mater are reflected in its blood bed, its specificity manifesting at the microcirculatory level.     

Microcirculatory bed of the pericardium under hypokinetic conditions]

The pericardium microcirculatory bed of rabbits was studied under conditions of hypokinesia of different duration. The state of hypokinesia was obtained by keeping the animals in small cages. The used methods were silver nitrate impregnation after Kuprijanov and injection of the vessels with the Parisian blue. Hypokinesia caused certain anatomical changes in all links of the microcirculatory bed. Disorders in the capillary-venular link were the first to appear. The alterations found should be considered as adaptational to effects of the extreme factor--hypokinesia.     

Structure and development of the microcirculatory bed of the pleural villi in man and animals

The structure of the microcirculatory bed in the pleural villi was studied by the method of impregnation with silver nitrate, after V.V. Kuprianov. In human and animal mediastinal pleura, the microcirculatory ways are regulated within polymerously repeated complexes--moduli. A characteristic feature of the pleural villi blood supply is the presence of capillary glomeruli with a vascular peduncle consisting of an arteriole and a venule. Four types of structure are revealed in the vascular peduncle consisting of an arteriole and a venule. Four types of structure are revealed in the vascular peduncle of the pleural villi. They were studied morphometrically. Correlation in the development of the villi microcirculatory bed and that of the vascular peduncle was stated. Participation of villous vessels in the regulation of fluid balance in the pleural cavity was discussed.     

Topography of the borderline structures of the anterior portion of the inferior mediastinum and their vascularization

By means of silver nitrate impregnation after V. V. Kupriianov of blood vessels it has been revealed that the blood microcirculatory bed of the borderline structures in the anterior part of the inferior mediastinum, united by their topographical proximity and common sources of blood supply, are characterized by a high concentration of microvessels, arterioles, precapillaries, capillaries, postcapillaries and venules. In each structure investigated peculiar features of the blood microcirculatory bed organization are defined. Richness in vessels and their borderline position ensure potency of transudation and resorption of liquids from the inferior mediastinum in the cases, when the mediastinal part studied becomes the reservoir for pathological exudates (at traumas, at mediastinitis).     

Microarchitectonics and microtopography of blood vessels of the human rectum

By means of injecting the vessels with 0.2% solution of silver nitrate after Ranvier, solutions of Indian ink and gas soot, impregnation after V.V. Kuprianov, the blood vessels of the rectal wall have been studied. The material has been obtained from 50 corpses of persons of various age, not suffering from any diseases of the gastrointestinal tract. The structural organization of the microcirculatory tract has been studied layer-by-layer, at all levels by means of atraumatic lamination of the tunics. Terminal links of the microcirculatory bed form zonal functional complexes of microvessels specific for each part of the rectum. They regularly repeat in a certain tunic and owing to this the whole organization of the microcirculatory bed acquires features of a definite polymeric structure which consists of homonomic complexes of microvessels. Their regularity, as regards their topography and quantity, definitely differs in each tunic and layer of the rectal wall. Precapillary sphincters and arteriolovenular anastomoses are revealed; they perform an active regulation of blood circulation in the organ. Diameters of the microvessels and density of the microcirculatory network have some slight fluctuations (differences) in functionally poorly active tunics of the rectal wall--the serous and submucous, especially in its rectosigmoid part. Differences of these parameters are especially expressed within the limits of the rectal ampule and its mucous and muscular tunics.     

Morphologic changes in the microcirculatory bed at stages of prolonged experimental fasting in animals

In 40 white male rats with body mass 180-200 g, by means of silver nitrate impregnation, morphological changes have been studied in the blood microcirculatory bed of the small intestine mesentery, spinal trapezoid muscle and eye ball conjunctiva at various stages of a prolonged fasting. With an increasing time of the experiment, a gradual undirected character of the changes in the microvessels is noted. After 3 days of fasting the changes in diameters of the microvessels, comparing to the control ones, have not any significant values in all the organs studied. After 6 days of fasting significant changes in diameters in all the links of the microcirculatory bed of the eye ball conjunctiva and in that of the spinal trapezoid muscle are observed. The microvascular changes are mostly pronounced on the 9th day of fasting. The maximal decrease of the microvessel diameters is noted in the eye ball conjunctiva, and the minimal--in the small intestine mesentery. The changes in the spinal trapezoid muscle are of intermediate character. The highest points of the structural lability gradient fall on the capillary and postcapillary-venular links of the blood microcirculatory bed.     

Reorganization of the lymphomicrocirculatory bed of human myocardium in ontogenesis

By means of Gerota mass and silver nitrate solution, injected into the myocardium and its vessels, as well as using the scanning electron microscopy technique for corrosive casts, links of the human myocardial lymphomicrocirculatory bed have been studied, beginning from 6-9-month-old fetuses up to elderly and old age persons. Changes in form, dimensions and amount per a volumetric unit have been stated in myocardial capillaries and postcapillaries. These signs demonstrate that the myocardial lymphatic system has different importance for each stage of individual development of the human heart.     

Comparative evaluation of the adaptive mechanisms of the microcirculatory bed during dehydration

In total preparations of the white rat small intestine mesentery, impregnated with silver nitrate, as well as under conditions of vital microscopical observations at certain stages of alimentary experimental dehydration, analogous changes in the microcirculatory bed links have been demonstrated. Comparison of quantitative parameters in decreasing diameters of the microvessels, specific for dehydrated preparations has shown a great importance of these changes in the impregnated preparations at the expense of tissue condensation at their histological treatment. The advantages of a complex application of both methods for estimating dynamics of vascular, intervascular and extravascular changes are proved.     

Variability in the diameter of the capillaries of the human heart during development

Seventy-eight hearts from persons, who had not suffered any cardiovascular disorders during their life time, have been studied. Microcirculatory bed vessels are revealed by impregnation with silver nitrate after V. V. Kuprianov. The values of the capillary diameters obtained are mathematically treated using T. H. Bayes formula. Periods of individual development of the heart are defined when a high functional activity of the capillary bed of the auricles and ventricles is noted. Evidently, this is one of the factors contributing to development of the cardiac ischemic disease.     

The system of bony canals as the basis for the angioarchitectonics of bones]

The spatial interrelationships of osteon canals were studied in corrosion preparations with the help of rastral electron microscopy. The structure of microvessels, their belonging to a definite link of the microcirculatory bed, the interaction of vessels and their position with respect to the osseous matrix were studied in bone sections impregnated with silver nitrate after V. V. Kuprijanov. Haversian canals in the compact substance of the bone are longitudinally oriented, can duplicate and form a single system of canals. The neighbouring canals of osteons might be bound by means of Volkmann's canals. The investigation of the Haversian canals in serial sections has shown that the diameter of the same canals of osteons can change at different levels, the diameter of the osteons themselves remaining unchanged. This seems to speak of uneven development of osteons in their different parts. In the Haversian canal there are one-two or occasionally three vessels having all three links of the morphocirculatory bed. The course and ramification of the vessel are identical to the shape of the osteon canal which includes them. The vessels are closely connected with the bony matrix by means of connective tissue bundles directed from the canal wall to the vessel wall. These bundles appear to serve as a peculiar anchor or amortizing apparatus and its elasticity might be a factor of a change of the shape and direction of the canal vessels in the bone development process.     

Vascular-nervous relationships in the valves of the heart]

Method of silver nitrate impregnation was used in order to study 50 preparations of not-changed atrioventricular valves of the heart of domestic bulls and 30 preparations of the same valves of adult humans. It has been shown that in heart valves there are certain relationships between striated muscle fibres, blood vessels and nerve elements. The nerve structures of the valves are represented by nerve bundles of different thickness. In their composition there are comparatively thin non-myelinated and thicker myelinated fibres. Towards the free edge of cusps the nerve bundles become thinner and the nerve trunks give off separate thin nerve fibres disposed along the vessels of a capillary type and in some places getting around them. In certain portions of cusps the nerve bundles, some of which have zigzag sinuosity, cross blood vessels in different directions. In man the major mass of blood vessels and nerve elements are disposed near the base of the valve cusps, accompanying the muscle fibre bundles penetrating from the base side. In the bull heart valves an amount of blood vessels and nerve elements is found in considerable portions of the cusps not connected with muscle fibres.     

Terminal vascular bed of the connective tissue membrane in hypoxic hypoxia]

Morphological changes of all links of the terminal vascular bed during acute hypoxic hypoxia were studied in experiment and in postmortem material. A complex of methods was used including microdissection, injection with India ink - gelatin, clearing, silver nitrate impregnation after V. V. Kuprijanov, staining after Van Gieson and with hematoxylin-eosin, biomicroscopy and reoencephalography. Signs of desorganization of the vascular bed were revealed which manifested themselves as changes in microangioarchitectonics and diameters of vascular lumens, increased permiability of their walls with saturation of them with white and escape of its forming elements of the blood outside the limits of the vessels, as well as in destruction of the aggregate state of the blood. It considerably enlarges our knowledge of the state and changes in the vascular bed during hypoxic hypoxia.     

Structural characteristics of the mediastinal pleura and its blood vessels

By means of impregnation of the microcirculatory bed vessels after V. V. Kupriyanov and transmissive electron microscopy, topological picture of hemomicrovessels has been estimated in the glomerular constructions of the dog mediastinal pleura. The composition of cell elements and peculiarities in distribution of the latter in the zone of the milk spots are examined. Their structural characteristics are manifested as presence of mesothelium of a decomplexated type accumulation of macrophagal and lymphocyto-plasma cells, glomerular organization of the capillary network and postcapillary venules, two types of endothelial lining of the metabolic microvessels. The role of the milk spots in ensuring immune protection, in migration of macrophages and in filtration of the pleural liquid is discussed.     

Effect of gravitational loads and hypokinesia on the structure of the blood vessels of the tongue in the rabbit]

The vessels of the tongue were studied in 120 rabbits in 5 series of experiments methods of injection, clearing, rentgenography, silver nitrate impregnation after V. V. Kuprijanov and a histological method. The animals were rotated in a centrifuge with a 1 m radius. For hypokinesia the animals were placed in small cages. Gravitation stress mainly caused changes in the capillary-venous part of the circulatory bed (dilatation of vessels). Under conditions of hypokinesia morphological changes were most pronounced in terminal portions of the arterial part of the bed, arterioles and precapillaries. Successive exposure to both factors caused no specific changes. Preliminary training to stressess failed to prevent the appearance of considerable morphological changes in blood vessels of the tongue.     

Vascular anastomoses of the blood microcirculatory bed of the human heart

Using a complex of morphological techniques both injective and non-injective, scanning electron microscopy including, the hemomicrocirculatory bed and vascular anastomoses have been studied in various parts of the human heart. In most cases anastomoses between the microcirculatory links are realized at the level of capillaries, precapillary arterioles and postcapillary venules. Venulo-venular anastomoses are demonstrated in the myocardium. Existence of terminal arterioles is discussed.     

Comparative morphometry of vessels of the microcirculatory bed of the cat pericardium in impregnated preparations and during in vivo microscopy

In impregnated (with silver nitrate) preparations of the cat pericardium and in photonegative pericardial microvessels photographed in vital experiments, diameters of the main vascular groups in the microcirculatory bed (arterioles, precapillaries, capillaries, postcapillaries and venules) were comparatively estimated. When impregnated, the vascular diameter decreases; the degree of the changes is not equal and depends on the wall structure. Therefore, when studying impregnated preparations, it is necessary to introduce the correction coefficients in order to make the data obtained comparable with the vital ones.     

Microcirculatory bed in the capsules of certain glands]

The capsules of the thyroid, submaxillary salivary, pancreatic gland of adults and the thymus of children were studed. The preparation were impregnated with silver nitrate after Kuprijanov and stained with haematoxiline-eosin. Different constructions of them microcirculatory bed depending on the character of the tissue and the functional activity of the organ were found. The value of the total cross section of the vessels of the microcirculatroy bed calculated in the capillary link allowed a comparisonof the degree of blood supply of the sheaths. The vascular bed of the sheaths served as anadditional way for the blood supply of the organ, a distribution basin and the site ofcollection of the blood, flowing from the parenchyma through collateral vessels.     

Development of the microcirculatory bed of the human tongue in the prenatal period

Morphofunctional regularities of formation and development of the blood microcirculatory bed in the human tongue have been studied in the prenatal period of morphogenesis. 119 human embryos and fetuses at the age of 5 weeks--9 months have been investigated. A complex of methods have been used: common histological (hematoxylin--eosin, after van Gieson and Mallory), injection of the lingual vessels with 20% suspension of Indian ink--gelatin, transmissive electron microscopy. General regularities of organogenesis, stages of the blood microcirculatory bed development and peculiarities of the process on formation of the primary protocapillary lingual blood bed are revealed. Regularities in structure of the terminal vascular constructions are studied for each structural element of the organ--mucosal membrane, muscles, glands, lingual tonsil. For these elements at the ultrastructural level certain features of the organic specificity in the structure of the blood microcirculatory bed links are determined.