Anatomic transformation of the lymphatic bed of the small intestine following immunization]

The experimental investigation of the lymphatic bed of the small intestine after immunization was performed in 15 rabbits. Ten rabbits were taken as control. The rabbits were immunized by administration of kidney antigen with the complete Freund adjuvant. The animals were killed on the 7-8th days after two cycles of immunization, three injections in each cycle. The interval between the injections was three days, between the cycles - one month. Polychrome injection of arteries and veins was made. The lymphatic bed was filled with Gerota's mass. The chylus sinuses, lymph capillaries and vessels of experimental animals were found to be dilated 2-6 times as compared with normal. There appear many blind processes on the walls of lymph capillaries and vessels. Intraorganic lymphatic pathways were more dilated as compared with extraorganic. The ileum was found to be more reactive in immunization than other two parts of the small intestine.     

Effect of gravitational loads of a training nature on the blood vessels of the rabbit spinal cord]

Three series of experiments were performed in 47 rabbits. The cerebral vessels were studied by methods of injection and clearing. In the first series under study were vessels after exposure to stresses of a training type. The picture of the circulatory bed under these conditions was close to normal in morphological parameters (diameter of vessels, amount of visible vessels, distinctness, evenness of the contours pronouncement of networks etc). In the 2nd and 3d series the results of training were checked by a single exposure to a series of stresses or a solitary stress. The data obtained suggest increased resistance in majority of trained animals to the following hypergravitation and better morphological parameters of the spinal cord circulatory bed as compared with not trained animals. Hence, certain adaptation to the following hypergravitation can be obtained in rabbits by means of repeated rotations in a centrifuge according to a special schedule of training.     

Age and local changes in the architectonics of the lymphatic bed of the wall of the jejunum and ileum in normal rabbits

Age and local changes of the lymphatic bed have been studied in the jejunum and ileum preparations obtained from 100 rabbits. The architectonics of the bed is stated to undergo some age and local changes. In fetuses and two-week-old rabbits, chyle sinuses are narrow and all flow into the capillaries of the tela submucosa. In one-month-old animals, the mucosal capillary network is developing and the chyle sinuses flow into it. In six--ten-month-old rabbits, intestinal bed is already formed, the chyle sinuses are wide. Aged changes are represented by a considerably rarefied networks, decrease in the chyle sinuses caliber, deformation of the sinus, capillary and vessel walls. In the jejunum, unlike the ileum, the chyle sinuses are of larger size and have more complex architectonics in the capillary networks of the mucosa and tela submucosa.     

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 of lymphatic vessels in the rat thyroid gland

The lymphatic bed of the thyroid gland has been studied in 24 intact rats. Three techniques facilitating to reveal lymphatic vessels in the organ have been used: preparation of semithin sections, injection of the blood bed with methyl methacrylate with a successive chemical extraction of the preparations, injection of the blood bed with liquid solution of methyl methacrylate with a consecutive study of the preparations in the scanning electron microscope. Methods of electron histochemistry (revealing horseradish peroxidase) and kryofractography have been applied. Construction of the thyroid lymphatic bed, structure of the wall are described, fibroblastic membrane (F-membrane) is revealed and the signs are presented, that allow to differentiate F-membrane from endothelium of the lymphatic capillaries. The pathways of lymph outflow in the rat thyroid gland consist of the following links: interstitial space in the interlobular spaces of the gland, into them the tissue liquor (lymph) is filtered ; plates of the F-membrane regulating direction of excessive albumin-containing liquor in the lymphatic capillaries, surrounding groups of 5-11 follicles, embracing the microlobule of the gland and situating in the interlobular spaces, deferent lymphatic vessels.     

The lymphatic bed of the liver in man and animal and its transformation in disordered bile outflow

The lymphatic bed has been studied in 141 hepatic preparations of the man, dog and white rat. Development of obturation in the common bile duct in the man and at modelling a similar process in the animals results in essential morphological adaptive-compensatory and destructive changes in the hepatic lymphatic bed. The adaptive-compensatory reconstruction is especially well seen at initial stages of the disease. It is manifested as a total dilatation of the bed, certain reserve elements get into work, the bed capacity increases. Then certain new structural units of the bed, collateral pathways develop. When the obturational process lasts long, certain destructive changes of the hepatic lymphatic bed elements take place. The change in the relief of endotheliocytes is their most characteristic sign. With increasing age of the patients the degree of the destructive rearrangements of the hepatic lymphatic bed increases. In the experiment carried out on the animals the lymphatic outflow from the thoracic duct is determined, being an indirect index of the hepatic lymph-forming function. An essential increase of the lymph volume, several times greater than in the control, gets from the duct into the venous bed. A connection is revealed between the morphological transformations of the bed components and its drainage function. The lymphatic bed of the liver performs also an active work concerning resorption and transport of bilirubin, its content in the organ rather increases, when the common bile duct is obturated.     

Effect of amino acids on transformation of glucose oxidase as antigen in tissues of immunized animals

The effect of certain amino acids on transformation of glucoseoxidase as an antigen in different tissues of the animals immunized with it showed that the used glucoseoxidase of the fungus Penicillium vitale Pidopl. et Bilaj possesses antigenic properties peculiar to this enzyme isolated from other sources. 1.5 minutes after a single administration of the antigen to nonimmunized rabbits it is determined in them in descending amounts in such an order: blood, lungs, liver, kidneys, lymphatic nodes. The same order is for immunized animals, but the enzyme quantity 1.5 minutes after the last injection is lower considerably in the kidneys, spleen, lymphatic nodes and in blood serum and changes slightly in the lungs and liver. The preliminary loading of animals under experiment immunized with amino acids accelerates essentially disappearance of the antigen under determination (glucoseoxidase in the given case) in the studied tissues. The data obtained testify to the fact that acceleration of antigen disappearance may be not related to interaction with antibodies.     

Intraorganic lymphatic bed of the cattle heart

Lymphomicrocirculatory networks of endocardium, myocardium and epicardium, as well as lymphatic vessels of four orders represent the intraorganic lymphatic bed of the cattle heart. In the endocardium there is a lymphatic network with close loops and a small amount of blindly beginning capillaries. The capillary lymphatic bed of the endocardial trabeculae carneae is much more dense than that in the other part of the endocardial surface. The spatial lymphatic network of the myocardium is joined with the lymphomicrocirculatory networks of the endocardium and epicardium by means of a large amount of connections. The epicardial lymphatic bed is formed by blindly beginning lymphatic capillaries, which situate in close and nonclose loops of the lymphatic network. In the epicardium there is only one lymphatic network. The size of the loops and the diameter of the lymphatic capillaries is directly proportional to the age of the animals.     

Effect of alcoholic intoxication on the lymphatic bed of the heart]

Cardiac lymphatic bed was studied in 120 male corpses at the age of 17--55 years, normal and of those died from alcohol intoxication and from cardiac ischemia. The methods of intratissue injection of coloured masses, impregnation after V. V. Kuprianov, histological and histochemical investigations were applied. Data in figures were obtained by means of a grid for cyto-, histo- and stereometric investigations and by a scanning integrant microspectrophotometer sim-2. Statistical data were obtained by a computer "Mir". It was demonstrated that the cardiac lymphatic system responds in a definite way to alcohol intoxication. Four forms of structural state in the lymphatic bed elements were revealed, specific density of its different components was calculated. A certain connection was noted to occur between morphological changes under the effect of toxic doses of alcohol; there was also a reaction of compensatory-adaptive elements of lymphodynamics. A number of pathological changes in cardiac tissues resulting in heart insufficiency were presented. Peculiarities in poisoning phases were demonstrated morphologically.     

Lymphatic bed of layers of the abdominal wall in the human inguinal area]

Lymphatic bed in the layers of the inguinal area was studied in connection with age in 70 human corpses. Polychromic injection of arteries, veins and lymphatic bed, staining of preparations after van Gieson, Weigert, with hematoxylin-eosin and morphometry were the methods applied. It was stated that lymphatic capillaries penetrate through all the layers forming the abdominal wall of the human inguinal area; they arrange interconnected networks in dermis, in external and internal oblique and transversal muscles and in their aponeuroses, as well as in fasciae and in the peritoneum. The lymphatic bed in question changes during ontogenesis. Age transformations of the lymphatic capillaries are in connection with functional loading on the anterior abdominal wall. Intraorganic connections existing between the lymphatic vessels of the anterior abdominal wall and the organs of the small pelvis (urinary bladder, uterus, rectum, etc.) are revealed, they are of a rather great interest for physicians.     

Various characteristics of the structure of the cardiac lymphatic bed and the morphofunctional basis of its insufficiency

Structural peculiarities of the cardiac lymphatic bed have been studied, as well as its adaptive and pathological changes under physical load, acute and recurrent coronary insufficiency under conditions of mechanical blockade of the lymph outflow from the organ, which have been modelled in dogs and rabbits. The cardiac lymphatic bed is injected with various staining masses and investigated stereoangioscopically in translucent preparations, in semithin slices and electron microscopically. The rearrangement of lymphatic capillaries and vessels revealed is of stereotypical character. The degree of manifestation and correlation of morphofunctional reactions, characterizing development of insufficiency of the cardiac lymphatic vessels is mainly determined by intensity and exposition of pathological effects, exercised on it, while etiologic factors are of less importance.     

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.     

The basic patterns in the development of lymph circulatory failure in the heart

63 adult rabbits were used to stimulate single physical exercise, acute and relapsing coronary insufficiency, alimentary atherosclerosis and to study adaptive and pathologic changes in the lymphatic channel (LC) of the heart. LC of the heart in animals with alimentary atherosclerosis after cholesterol exclusion from their diet was studied to determine reversibility of these changes. LC of the heart was injected by differently coloured masses and was investigated by the stereoangioscopic method on clarified preparations, on semithin sections and by the electron-microscopic method. Changes in different elements of a lymphatic net were of the stereotype character, as a whole. Morphofunctional reactions determining the development of the chronic insufficiency of the lymph flow in the heart form as successively following phases which change both due to exposition of the pathological process-initiated effect and due to certain endogenic factors arising during arrangement of LC of the heart.     

The relationship between the lymphatic vessels of the nerves of the human lower extremity and the perineural spaces]

The lymphatic vessels and perineural spaces of superficial and profound nerves of the extremity were studied on the material of 50 lower extremities of corpses of humans by the method of intratissue and direct injection. Initial lymphatic capillaries and extraorganic lymphatic vessels and their paravasal plexuses were found. It is concluded that closed lymphatic capillaries having no immediate connection with the perineural space are the roots of the lymphatic bed in the nerve.     

Morphofunctional changes in the hemo- and lymphomicrocirculatory bed of the uterus and its regional lymph nodes in venous congestion during pregnancy

Interrelations of the blood and lymphatic systems of the uterus have been examined in rats at pregnancy complicated with the ++phlebo-occlusive syndrome. Blood stream impediment in the caudal vena cava results in increasing diameter of the arterioles, capillaries and venules of the endo- and myometrium. Certain disturbances of blood circulation in the uterus at the ++phlebo-cclusive syndrome in the pregnancy animals, as a rule, reflect in the uterine lymph outflow; this is demonstrated as dilatation and deformity of the lymphatic vessels and capillaries, appearance of protrusions of the lymphatic vessels wall. There is a definite co-ordination in the reaction to the caudal vena cava occlusion in the intra-, ++extra-organic uterine lymphatic bed and in its regional lymph nodes, manifested as the following morphological signs: decreasing relative volume, that the lymphoid tissue occupies and increasing relative volume of the cortical and medullary intermediate sinuses.     

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.     

Structural and metabolic changes in the limbic cortex of the rabbit in response to experimentation with the hypothalamus

By means of the light and electron microscopy, histochemical and cytophotometrical methods the anterior subarea of the cerebral limbic cortex has been studied in 30 experimental and 30 control rabbits. The experimental animals have been given 3, 15 and 30 sessions (1 h per day) of electric irritation (0.05 mA, 50 Hz, 1 msec) on the posterior hypothalamic field (PHF). Twelve rabbits from 30 control animals make an intact group and 18--a group with inactive electrodes inserted into the PHF. After 3 and especially after 15 sessions it has been revealed: in neurons--an acute swelling, edematous alterations, hyperchromatosis and shrinkage, changes in lactate dehydrogenase, succinic dehydrogenase, nicotinamide-adenine-dinucleotide-diaphorase and nicotinamide-adenine-dinucleotide-phosphate-diaphorase activities, in neuroglia--hypertrophy and weakly manifested hyperplasia. After 30 sessions synapses degenerated after the dark type are revealed. More intensive structural and metabolic changes are noted in the middle cytoarchitectonical complex. The changes of the enzymatic activity are considered as certain signs of weakening mitochondrial processes, connected with energy production, increasing glycolysis, decreasing level of the energetic provision of the cytoplasmic synthesis, arising under conditions of a disturbed transneuronal influence on the cortex by the hypothalamus.     

Transient immunosuppression stops rejection of virus-transduced enhanced green fluorescent protein in rabbit retina

The expression of lentivirus-transduced enhanced green fluorescent protein (EGFP) was detectable in rabbit retinal pigment epithelium (RPE) within 3 to 5 days after subretinal injection of the vector. Within 2 to 3 weeks, EGFP-expressing cells were eliminated by rejection. In the current experiments, we monitor serum antibody titers for EGFP before and after transduction and determine whether systemic immunosuppression prevents recognition of EGFP by the immune system. While all control rabbits developed antibodies against EFGP and showed signs of rejection, no such evidence was observed with animals which received immunosuppression. One month of systemic immunosuppression permanently prevented rejection of RPE with EGFP expression. Fluorescence has been maintained for more than a year. If a control eye was injected with the same virus after terminating immunosuppression, both eyes showed signs of rejection. The lack of rejection is not due to tolerance but to a failure of the animals to detect the foreign protein. Detection must depend upon a brief window of time after surgery needed to introduce the vector, perhaps related to a concurrent but transient inflammation. This strategy may be useful in managing other types of rejection in the retina.     

Anatomy of the lymphangions of the small intestine

Anatomy of lymphangions (valve segments) has been studied in 120 human and animal cadavers. Methods of investigation were: polychrome injection of arteries, veins and lymphatic bed; macro-microscopic preparation; staining of histopreparations after van Gieson, hematoxylin-eosin, complex technique after A.V. Borisov (1973); impregnation after V.V. Kuprianov (1965); detection of bundle collagene fibers after Mallory and elastic fibers after Weighert. The data collected on the lymphangions demonstrate that the valve segments (lymphangions) in the small intestinal wall appear in phylogenesis at first in birds. Avian lymphangions are cylindric and the valves are of semilunar form and the distance between them is 2--3 cm. In predators (dog, cat, fox, marten) lymphangions are round or conical. Their size is within 6--8 mm. In other animals (rodents, Artiodactyla, Perissodactyla) the lymphangions are 3--5 times longer comparing their width. In human ontogenesis the valve segments of the lymph vessels are formed in tela submucosa of the small intestine in 6--7-month-old fetuses. Some other peculiarities in animal and human anatomy of lymphangions have been revealed.     

Acclimatization to neurological decompression sickness in rabbits

Diving acclimatization refers to a reduced susceptibility to acute decompression sickness (DCS) in individuals undergoing repeated compression-decompression cycles. We demonstrated in a previous study that the mechanism responsible for this acclimatization is similar to that of stress preconditioning. In this study, we investigated the protective effect of prior DCS preconditioning on the severity of neurological DCS in subsequent exposure to high pressure in rabbits. We exposed the rabbits (n = 10) to a pressure cycle of 6 absolute atmospheres (ATA) for 90 min, which induced signs of neurological DCS in 60% of the animals. Twenty-four hours after the pressure cycle, rabbits with DCS expressed more heat-shock protein 70 (HSP70) in the lungs, liver, and heart than rabbits without signs of disease or those in the control group (n = 6). In another group of rabbits (n = 24), 50% of animals presented signs of neurological DCS after exposure to high pressure, with a neurological score of 46.5 (SD 19.5). A course of hyperbaric oxygen therapy alleviated the signs of neurological DCS and ensured the animals' survival for 24 h. Experiencing another pressure cycle of 6 ATA for 90 min, 50% of 12 rabbits with prior DCS preconditioning developed signs of DCS, with a neurological score of 16.3 (SD 28.3), significantly lower than that before hyperbaric oxygen therapy (P = 0.002). In summary, our results show that the occurrence of DCS in rabbits after rapid decompression is associated with increased expression of a stress protein, indicating that the stress response is induced by DCS. This phenomenon was defined as "DCS preconditioning." DCS preconditioning attenuated the severity of neurological DCS caused by subsequent exposure to high pressure. These results suggest that bubble formation in tissues activates the stress response and stress preconditioning attenuates tissue injury on subsequent DCS stress, which may be the mechanism responsible for diving acclimatization.