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.     

Structural changes and hemodynamic relations in the microcirculatory bed of the mesentery of the white rat during the period of sexual maturation

Structural changes and hemodynamic relations have been studied in the microcirculatory bed of the white rat small intestine mesentery during sex maturation (from the 3d up to the 10th week of the postnatal development). All calculations are performed regarding the mesenteric segment limited with two intestinal arteries, which is considered as an elementary microvascular module. Complication of the microcirculatory bed construction takes place at the expense of increasing number (nearly five-fold) of microvessels in the segment and increase of the capillary network density. The hemodynamic factor plays a certain role for stimulating the process of the capillary growth. The definitive structure of the mesenteric microcirculatory bed is completed by the 7th week. The main rearrangement of the microcirculatory system during the developmental process from a simple arterio-venular loop up to a complex microcirculatory bed with a branching capillary network is performed within the limits of the mesenteric segment.     

Morphometric findings in the microcirculatory bed of the sigmoid serosa during the fetal period in man

During fetal life, formation and arrangement of the microcirculatory bed in the serous membrane of the sigmoid colon correspond to the growth and functioning of the latter at different stages of ontogenesis. Two periods in the development of the microcirculatory bed of the serous membrane of the sigmoid colon are revealed: the first period coincides with the first half of the fetal development when capillary growth is considerable, i.e. with the growth of metabolic part in the microcirculatory bed; the second period coincides with the second half of the fetal development when intensified growth of the sigmoid portion of the large intenstine and its transport sections in the microcirculatory bed (arterioles, precapillaries, postcapillaries, venules) are observed.     

The blood microcirculatory bed of the tunica muscularis of the human esophagus in postnatal ontogeny]

The analysis of morphological and morphometrical data of the muscular membrane and its blood microcirculatory bed has demonstrated that their development during the postnatal ontogenesis advances unevenly. An intensified growth and development of the muscular membrane morphological structures, including its blood microcirculatory bed occurs from 3 up to 30 years of life. Their maximal growth is noted from 12 up to 30 years of age. The stages of intensified development of the muscular membrane and its blood microcirculatory bed change into stages of retarded growth, where processes of involutive character preponderate. This is especially noticeable from 60 and more years of age. The stages noticed in the muscular membrane development and its blood microcirculatory bed are characterized both by general and topographical morphofunctional peculiarities specific for every stage of organogenesis.     

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.     

Analysis of the structural parameters of the blood flow pathways in the microcirculatory system]

The reconstruction of the mesenterium microcirculatory bed was performed intravitally in albino rats and cats after biomicrophotograms. The number, length and caliber of arterioles, pericapillary arteriolec, capillaries, postcapillary venules and venules of the mesenterium were measured. According to these data summary indices of the cross section, surface and volume of the vessels of various functional subdivisions of the microcirculatory bed were calculated. The blood volume entering the microcirculatory system of the albino rat's mesenterium is distributed in the vessels as follows: 8,4% -- arterioles, 10,2% -- pericapillary arterioles, 41,9% -- capillaries, 22,1% -- postcapillary venules and 17,4% -- venules. Similar correlations were found in the cat. The working surface of capillaries is 60--70% of the working surface of all the vessels of the mesenterial microcirculatory system. The evidence of the functional variability of the microcirculatory bed geometry depending on the tissue needs in blood supply is presented.     

Use of hematoxylin to demonstrate the microcirculatory bed in full-thickness objects and sections of the wall of the gastrointestinal tract]

Slight modifications of the widely applied hematoxylin method of staining make it possible to reveal completely microcirculatory bed in total film preparations and in histological sections of the gastrointestinal wall. Hematoxylin staining of all elements in the vascular wall and the surrounding tissue helps to differentiate definitely every component of the microcirculatory bed and to demonstrate vascular-tissue and vascular-neural interconnections in film preparations and histological sections.     

Results and prospects for the study of the morphologic basis of microcirculation of the blood

The survey of the works, performed during the 11th five-year period in studying general biological regularities of microcirculation, demonstrates certain success in investigations developed in the following directions: functional geometry of the hemo-microcirculatory bed; elaboration of quantitative and qualitative analysis methods of the microcirculatory system elements; functional morphology of the vascular endothelium; experimental analysis of adaptive mechanisms of the microcirculatory bed; clinical-morphological investigations of microcirculation. Formation of structural-functional units, ensuring specialization of microcirculation in organs, forms the base of the functional geometry of the microcirculatory bed. This makes necessary conditions for compartmentalization of some micro-region in an organ and spatial distribution of various liquid media in dependence of certain topology of microvessels. The most perspective ways in development of morphological investigations, concerning the general biological regularities of microcirculation, are discussed.     

Ultrastructural characteristics of the microcirculatory bed of the human adrenal cortex in prenatal ontogenesis

By means of transmissive electron microscopy the adrenals have been studied in 25 human embryos and fetuses at the age of 6-36 weeks. Certain stages have been revealed in formation of the adrenal cortex microcirculatory bed. In 6-7-week-old embryos (period of diffuse protocapillary bed) endothelial structure and mesenchymal cells, surrounding the adrenal anlage, resemble one another. A distinguished feature of the endothelium is regularly revealed desmosomes and large vacuoles, often found in cytoplasm of endotheliocytes. In 8-12-week-old fetuses (period when the organospecific microcirculatory bed is forming) sinusoid capillaries differentiate in the internal zone of the adrenal cortex; in endothelium fenestrae, "hatches", "locks" are revealed, the capillary basal membrane is formed. During subsequent time of the intrauterine development perfection of the microcirculatory pathways in the adrenals takes place, the arteriolar link of the subcapsular layer including. By the time of birth morphofunctional maturity of the microcirculatory bed in the adrenal cortex is noted.     

Formation of the microcirculatory bed of the muscle coat of the wall of the sigmoid colon during human fetal development]

During intrauterine life microcirculatory bed of the muscular coat is forming and developing in accordance with its differentiation, growth and functional changes at various steps of its ontogenesis. This step-like differentiation in the parts composing the microcirculatory bed and the whole microcirculatory network of longitudinal and circulatory layers of the muscular coat is genetically connected with differentiation taking place in the wall of the sigmoid colon during the developmental period studied and, in the end, reflects morphological maturation of the sigmoid colon at different stages of its individual ontogenesis.     

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.     

Morphology of the microcirculatory bed of the vascular coat of the human eye]

Recently ophthalmologists got interested in microcirculatory bed of the choroid (the main collector of blood in the eye) because of the vascular layer was studied in 25 eyes of persons who had died suddenly and had no eye pathology during their lives. The age was from 11 to 70 years. V. V. Kuprianov's method of impregnation was used. Structural peculiarities of the choroid microcirculatory bed were presented; its changes were stated to depend on functional importance of the given segment of the eyeground and on the age of the patient. The data obtained could facilitate in studying different pathologic conditions in the eye in order to clarify the role of the choroid microcirculatory bed in genesis of ophthalmic diseases.     

Effect of chronic alcoholism on the state of the microcirculatory bed of the myocardium

Ultrastructure of myocardial capillaries of rats was studied in cases of chronic alcohol intoxication, experimental alcoholic cardiomyopathy (ACM) and its correction with antioxidants (vitamin E, dibunol). Alterations in the microcirculatory bed were similar in all groups of animals irrespective of disturbances in cardiomyocytes. Cardiomyocyte ultrastructure was improved after treatment with antioxidants, but capillary bed was the same as in untreated animals. High dibunol doses caused the onset of perivascular sclerosis. Disturbances in the microcirculatory bed are, probably, the first step in the determination of ACM pathogenesis and therapy of ACM must be directed at the correction of both alterations of cardiomyocytes and capillary bed.     

Vascularization of the myenteric plexus in the small intestine of pigeons]

By means of light and electron microscopy vascularization of the myenteric plexus has been studied in the pigeon small intestine. Ganglia of the plexus, their cell composition, ultrastructure of neurons have been described. Links of the microcirculatory bed of the intramural ganglia are characterized, interrelations of capillaries with neurons are described, quantitative estimation of microhemovessels, surrounding the microcirculatory bed of the myenteric plexus in the intestinal wall in birds and mammalia.     

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.     

Development of the uterine microcirculatory bed in postnatal ontogeny

Age peculiarities of common structure of the microcirculatory pathways, specific volumes and amount of microvessels, zonal parameters of pericapillary microcirculation of metabolites, glycosamine glycans and glycoproteins contents, phosphatase and ATPase activity, collagen and elastic fibers of the microcirculatory bed vessels have been studied in 190 unchanged uteri, beginning from 36-week-old fetuses up to 35 years of age. The microcirculatory bed of myometrium during the period of postnatal ontogenesis investigated possesses a polymer-homonomous structural organization; its base make myoangiomas, including the terminal arteriole with precapillaries and collecting venule, that run from it. Similar structure of the myometrium microcirculatory pathways is already observed in fetuses of late antenatal period. In endometrium formed glanduloangionomas are revealed in the prepubertal age. Increase in glycosamine glycans contents is stated in the microvessel walls and in the uterine stroma during the process of its development. Compensatory-adaptive changes in the uterine microcirculatory bed are described during the newborn period up to the puberty. Functionally mature structures of the microcirculatory pathways in the submucosal and vascular layers of myometrium, endometrium and in the cervix uteri are found to be formed earlier than in other areas of the organ.     

Hemo- and lymphomicrocirculatory bed of the broad ligament of the uterus in the presence of collateral circulation

Structural adaptation of the vascular bed in the broad ligament of the dog uterus has been studied at various time of the experimental phlebohypertension. Restitution of the circulation after the posterior vena cava occulsion occurs phasically. The venous collateralies are not formed at one time and it is connected with the venous pressure level in the inferiocaval system and with some changes in the construction of the microcirculatory bed. Basing on the morphometry data, a general equation has been derived which reflects dynamics of the microangiological parameters and demonstrates unidirectionness of the adaptive reactions in the vascular bed at the disturbed venous circulation. Using principles of the system-structural analysis and the mathematical graph theory, we consider the microcirculatory system of the broad ligament of the uterus as a graph-system and study the reorganization of the microcirculatory network at a venous congestion. Realization of the compensatory possibilities is reached in the microcirculatory bed by a changed relationships in the number of the intervascular connections. The latter are estimated according to the graph-schemes of the microvascular bed. Morphokinetics of the connections between the vessels is characterized by widening or narrowing the borders of the "adaptive norm" and by changing the microangioarchitectonics. At the same time, there is noted formation of specialized microhemoangioconstructions. Morphofunctional state of the lymphatic system is connected with reorganization of the angioarchitectonics. This is certain manifestation of the law of the lymphatic and blood beds "synergism". Thus, the structural changes of the vascular bed are aimed to support a certain hemodynamic level.     

The microcirculatory bed of the human heart

Using a complex approach in studying microcirculatory bed of the human heart, possibilities of scanning electron microscopy of corrosive preparations, those of silver nitrate impregnation after V. V. Kuprianov are demonstrated. The silver nitrate impregnation makes it possible to study the wall structure of the microcirculatory pathways, to analyse arrangement of nuclei in the endothelial and muscle cells of the microcirculatory links, to reveal together with the vessels the surrounding tissues. Scanograms of the corrosive preparations of the arterioles demonstrate "circulatory strips", that are absent in the venular part. The relief of the luminal casts of the microcirculatory bed vessels in the human heart is presented as impresses of nuclei of the endothelial and smooth muscle cells. Peculiarities in form and distribution of these nuclei in various links of the microbed are demonstrated.     

MIcrocirculatory bed of various internal organs in modeling of the inter-atrial shunt

At modelling a congenital heart failure--defect of the interatrial septum during late stages of the experiment, dilatation of the pulmonary artery and certain changes in the microcirculatory bed of the lungs, oesophagus, stomach and colon are observed. It has been demonstrated histologically and morphometrically that in adaptive reactions of the blood bed an important role belongs to the arteriolar part and metabolic link of the microcirculatory bed of the organs investigated. The changes in the pulmonary vessels are insufficiently expressed and possibility of hypertension in the lesser circulation is not great.     

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.