Phosphatase activity in the lymph during a fever reaction]

Activity of acid and alkaline phosphatases, as well as isoenzymes of alkaline phosphatase in the lymph of the thoracic lymphatic duct, hepatic lymph and the peripheral blood have been studied on rabbits in the dynamics of the fever reaction of different duration. The fever reaction was followed by enzyme activity increase in all the body biologic fluids. However the degree of increase of their activity in the lymph was greater that that in the blood. Our data indicate that in the transport of phosphatases released from the tissues in the common circulation the essential role is played by the lymphatic system, the resorption and transport functions of which significantly characterise the dynamics and the level of their changes in the blood in fever reaction.     

The lymphatic vasculature in disease

Blood vessels form a closed circulatory system, whereas lymphatic vessels form a one-way conduit for tissue fluid and leukocytes. In most vertebrates, the main function of lymphatic vessels is to collect excess protein-rich fluid that has extravasated from blood vessels and transport it back into the blood circulation. Lymphatic vessels have an important immune surveillance function, as they import various antigens and activated antigen-presenting cells into the lymph nodes and export immune effector cells and humoral response factors into the blood circulation. Defects in lymphatic function can lead to lymph accumulation in tissues, dampened immune responses, connective tissue and fat accumulation, and tissue swelling known as lymphedema. This review highlights the most recent developments in lymphatic biology and how the lymphatic system contributes to the pathogenesis of various diseases involving immune and inflammatory responses and its role in disseminating tumor cells.     

Changes in hemolymphocoagulation in acute arterial occlusive diseases of the lower extremity

In the present, on the 20 mongrel dogs, the authors studied the changes of coagulation in the blood and lymph in acute occlusion of thigh artery. The results of research show that during the development of pathological process the hypercoagulation displacements were observed in the blood-vascular and in lymphatic links of humoral transport. Increase in coagulation of lymph is one of the possible reasons of difficulty for lymph drainage++ of the injured organ.     

Lymphatic transport of cellular enzymes from muscle into the intravascular compartment.

In an experimental study, employing anaesthetized dogs, it was investigated whether cellular enzymes from peripheral skeletal muscle get into the circulating blood by diffusion across capillary membranes or by lymphatic transport. In the experimental group 1, the animals were anaesthetized only. The plasma activities of the four enzymes measured--lactate dehydrogenase, aspartate aminotransferase, alanine aminotransferase, creatine kinase--did not show any mentionable change during a time period of 6 h. In group 2 one hind limb of each animal was moved passively for 1 h. Alanine aminotransferase remained unchanged in plasma, the activities of the three other enzymes increased significantly. In group 3 one hind limb was made hypoxic by clamping the femoral blood vessels for 1 h. No activity changes were observed. When the period of hypoxia was followed by a 1-hour period of passive movement in group 4, the alterations in plasma activities were almost identical to those observed in group 2. In group 5 the experimental procedure was as in group 4, in addition the lymph from the thoracic duct was quantitatively withdrawn. The enzyme activities in plasma revealed a tendency to decrease rather than increase. Lymph flow increased significantly as well as the lymphatic activities of those enzymes which have high intracellular activities in muscle. The results prove, that enzymes from muscle are transported from the interstitial into the intravascular compartment mainly by lymphatic transport. Indications were found that the interruption of blood flow in one hind limb did not result in an enzyme release from muscle cells. It is discussed how changes in lymph flow, occurring during physical exercise for example, affect enzyme activities in plasma.     

Enzyme activities in thoracic duct lymph and plasma of anaesthetized, conscious resting and exercising dogs

The significance of changes in lymph flow for the extracellular distribution and transport of cellular enzymes and for the level of enzyme activities in plasma was investigated. Specimens of thoracic duct lymph were obtained from an extracorporal lymph shunt in anaesthetized, conscious resting and treadmill exercising dogs (6 km X h-1 for 1 h) The activity of 10 enzymes and of protein content in lymph and plasma were studied, as well as lymph flow, lymphatic transport, and the lymph-plasma ratio of these compounds. Lactate, pH, and blood gases were monitored in venous blood. Lymph flow of 0.80 ml X min-1 in anaesthetized dogs more than doubled (to 1.86 ml X min-1) when the animals were conscious and resting. In anaesthetized dogs lymph enzyme activity was higher only for enzymes of predominately hepatic origin, such as choline esterase (CHE) and alanine aminoferase (ALAT), and was lower for aspartate aminotransferase (ASAT) and aldolase (ALD). In conscious dogs, due to activation of the skeletal muscle "tissue pump", lymphatic transport of enzymes with rather high activity in skeletal muscle, and of protein, is significantly enhanced. Enzyme activities in plasma, however, did not differ between the groups. Lymph-plasma activity ratios higher than one were found for lactate dehydrogenase (LDH), malate dehydrogenase (MDH), ASAT, creatine kinase (CK), ALD, and phosphohexose isomerase (PHI). Exercise stimulated lymph flow up to 4.9 ml X min-1, and increased the lymphatic activities of those enzymes with a lymph-plasma ratio higher than unity, these enzymes increasing in the plasma due to the highly increased lymphatic transport.(ABSTRACT TRUNCATED AT 250 WORDS)     

Transferase contents in lymph and blood in fever reaction]

The aim of the present investigation was the study of the content of alanine, asparagine-transaminases, gamma-glutamyl transferase and their isoenzymes, as well as leucine aminotransferase in the lymph of thoracic duct, hepatic and intestinal lymph and peripheral blood in dynamics of fever reaction of various duration in the experiments on rabbits. Irrespective of its duration, the fever was followed by a significant activation of the enzymes in the body fluids. However, in many-day fever reaction, a rise of enzymes level in the lymph was more prolonged than that in the blood. The above studies make it possible to assume that the released enzymes in fever reaction are primarily resorbed by lymphatic capillaries and their activity indices in the blood serum are largely evidenced by the transport function of the lymphatic system.     

Effect of obsidan on metabolic processes in the blood and lymph in acute myocardial infarction

The effects of obsidan on lactate and glucose levels, the indices of ABB and electrolyte metabolism in blood and lymph at various times after development of the acute myocardial infarction were studied experimentally on dogs. It was stated that the earliest and most expressed changes of biochemical values were observed in the lymphatic system, thus pointing to its important role in the resorption and transport of the metabolic products from ischaemic myocardium. The use of obsidan during the development of acute myocardial infarction corrects substantially the disturbed metabolic processes in the blood and lymph.     

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.     

Contractile activity of pectoral channel and lymph nodes in rats under antiorthostatic influences

It has been established that during short term body antiorthostatic positions lymphatic system carries out compensatory function, unloading the cardiovascular system from redundant exercise. The contractile activity of pectoral channel and lymphatic nodes in weightlessness (antiorthostatic influence) was studied. The functional role of neck lymph nodes is expressed by depositing of liquid during redistribution of the blood. The atony of neck lymph nodes as well as loss of pectoral channel and lymph nodes decrease the receptor sensitivity of vessels and nodes to the action of vasoactive substances.     

Lymphatic smooth muscle: the motor unit of lymph drainage

Embedded into the wall of collecting lymphatic vessels and trunks, the lymphatic smooth muscles are cardinal to the functions of the lymphatic system. Their intrinsic contractile property--the intrinsic lymph pump--through rhythmical and phasic contractions of the vessels, represents the principal mechanism by which lymph flow is generated. Through changes in tonic constrictions, lymphatic smooth muscles also modulate lymph flow resistance. Lymphatic smooth muscles are sensitive to physical and chemical stimuli, mediating changes in their activity and modulating lymphatic drainage. Because lymphatic smooth muscles play such an important role in fluid transport, their dysfunction may be a component of many inflammatory disease states. This review presents recent findings on the physiology and cellular biology of lymphatic smooth muscles and discusses the importance of these cells for the function of the lymphatic system in physiological and pathophysiological situations.     

On the respiratory function of human blood platelets

A set of physiological parameters of the blood from healthy individuals and patients with hypochromic anemia was subjected to factor analysis in order to test the hypothesis that platelets perform a respiratory function in circulation. Platelets were shown to have no respiratory function comparable to that of erythrocytes; however, the state of the pool of circulating platelets was of significance for blood gas exchange and rheology. When interpreting the extracted factors and observing the type, strength, and dynamics of the correlations found, we suggested that the effects of platelets on blood gas exchange and rheology were indirect, mediated by the platelet pool of biologically active substances. Being involved in the regulation of microcirculation and vessel wall permeability, platelets modulate the erythrocyte transport function.     

Structural studies on lymphomyeloid tissues of the dogfish,Scyliorhinus canicula L.

The structure and ultrastructure of the lymphomyeloid epigonal and Leydig organs of the dogfish Scyliorhinus canicula L. were investigated. The tissues produce leucocytes, mainly granulocytic cells, but also some lymphocytes and plasma cells. Lymphocytes sometimes form nodule-like aggregations, especially in the epigonal organ. Granulocytes are probably stored within the lymphomyeloid tissues and enter the circulation on maturation. They may also release biologically active substances into the blood.     

Morphofunctional indices of the effects of pyracryl on the organs of female genital system in rats

Morphofunctional indices of pyracryl (phosphate poly-2-pyridylethylmethacrilate) effecting reproduction system of Wistar rats have been studied. It has been shown that monthly administration of pyracryl in doses 1 mg/kg and 5 mg/kg lead to infiltration of mast cells and their pronounced degranulation and impairment of blood and lymph microcirculation. As far as gonadotropic effect is concerned, its parametres depend on the administration of pyracryl. Pyracryl in doses of 1 mg/kg stimulates folliculogenesis in ovaries, a dose of 5 mg/kg may cause expressed atresia of growing follicules and changes of oestrous cycle. It is suggested that biologically active substances of mast cells in female reproduction system play an important role in realization of gonadotropic effects of pyracryl.     

The movement of fluids and substances in the testis

Three aspects of the control of movements of fluids and substances into, out of and inside the testis are discussed: the tubular barrier, the interstitial extracellular fluid and the testicular blood vessels. The functional basis for the tubular barrier is twofold; there are significant differences in the concentration of many substances inside and outside the tubules and marker substances enter or leave the tubular fluid at widely different rates, depending on lipid solubility and the presence of specific carrier systems. The anatomical basis for this barrier appears to be the specialized junctions between adjacent pairs of Sertoli cells. The barrier develops only at puberty, as the first cells undergo meiosis, but the development may not be as sudden as previously believed. The barrier breaks down after efferent duct ligation when spermatogenesis is disrupted. Techniques for measuring the volume, the turnover rate, the composition and fate of the interstitial extracellular fluid are described, and the unsatisfactory features of the presently available techniques for collecting this fluid for analysis are emphasized. There is a relationship between the fluid in the testis and lymph from vessels in the spermatic cord and lymph may be important for the transport of hormones to the general circulation in some circumstances and to other organs close to the testis. The testicular blood vessels display certain unusual features, a very high susceptibility to the toxic effects of cadmium salts, a high level of alkaline phosphatase activity in all endothelial cells but only after puberty and a high level of gamma-glutamyl transpeptidase in the endothelial cells of the arterioles and the testicular artery. These same cells are the site for a specific transport system for leucine and phenylalanine, with kinetic characteristics similar to the system in brain. Flow of blood may limit hormone secretion by the aspermatogenic testis, but diffusion limitation may also be important under some circumstances. A fuller understanding of the ways in which substances move around in the testis, particularly how they cross the endothelial cell layer or penetrate into the tubules, will be important for a better appreciation of testicular function.     

The pharmacokinetics of intravenously administered diazepam in the rat influenced by composition of the lymph

Diazepam, a drug with hydrophobic properties, was used as a model drug for the study of its distribution after i.v. administration into the central lymph of the rat. The intestinal lymph, which prevails in the central lymph, was modified for the presence of total lipids chylomicrons by fasting and a normal or an artificial diet (olive oil). Lymphatic levels of diazepam in all three experimental conditions exceeded the corresponding blood levels, being lowest in the fasted group, higher in the normally fed animals and highest in the oil-fed group. Experimental blood and lymphatic data were subjected to pharmacokinetic analysis. The changes in the parameters were found to depend quantitatively upon the presence of chylomicrons in the lymph. Lymphatic availability of diazepam in the central lymph is stimulated by an increased content of the chylomicrons fraction of the lymph.     

Evaluating flux of labeled albumin into the pulmonary interstitium of sheep lungs.

A noninvasive method was used to measure the movement of 131I-labeled albumin across the pulmonary microvascular barrier of a blood-perfused in situ sheep lung lymph preparation. After injection of labeled albumin into the blood, external measurements of gamma activity were taken for 2 h. The interstitial concentrations were calculated by applying the external activities and sampled lung lymph concentrations to a mass transport model. For the external activities and lymph activities to yield the same quantitative results, two modifications were necessary. First, lymph concentrations were corrected for transport delay from the lymphatic system. Second, externally detected radioactivity had to be corrected for the contribution of unbound nuclide. Application of a mathematical model to the data indicated the extravascular distribution volume for albumin was 79% of the pulmonary blood volume, and the extravascular distribution volume for radiolabeled iodide was 4.42 times greater than the pulmonary blood volume. The permeability-surface area product for iodide in the lung was estimated to be 0.274 ml.min-1.g blood-free dry lung wt-1. The transport delay in the lymphatic system was approximately 30-45 min and represented a volume of 1.44-2.80 ml.     

Lymph pools in the basement, sump pumps in the attic: the anuran dilemma for lymph movement

Amphibians are a vertebrate group transitional between aquatic and terrestrial environments. Consequently, both increases and decreases in blood volume are a natural biological stress associated with aquatic and terrestrial environments. In comparison with other vertebrate classes, anuran amphibians have the most rapid compensation and greatest capacity to compensate for changes in blood volume and survive dehydration. Unlike in mammals, a Starling transcapillary uptake mechanism does not account for this fluid mobilization because lymph flow is a substantial and important additional factor. The role of the lymphatic system in flux of fluids back into the circulation varies interspecifically in anurans and is an order of magnitude greater in anurans than in mammals. Current models of lymph movement in anurans are centered on the role of lymph hearts, but we suggest that these models are untenable. We present a new hypothesis for lymph movement involving (1) pressure differences created by compartmentalization of the hind limb lymph spaces into sacs of serially graded compliance to move lymph horizontally and (2) both negative and positive pressure differences created by contraction of skeletal muscles to move lymph vertically. The primary function of some of these skeletal muscles may be solely for lymph movement, but some may also be involved with other functions such as pulmonary ventilation.     

Morphological analysis of transportation pathways of microspheres after their introduction into the uterine horn cavity in cyclic pigs

Countercurrent transfer is thought to be one of the most important mechanisms involved in the transfer of substances between the uterus and oviduct. The present study was aimed at recognizing other putative transportation pathways from the uterine cavity through the oviduct onto the surface of and into internal ovarian structures. Microspheres (latex beads, 0.8 m in diameter) were introduced into the uterine horn cavity of pigs, for 30 min, at various days of the estrous cycle. The transportation pathways of the beads were then analyzed by light and electron microscopy. The transport of microspheres through the oviduct canal into ovarian tissues took place on each day of the estrous cycle. The largest numbers of microspheres passed through the tunica albuginea to the corpora lutea. Some of microspheres also reached the surface of the uterine ligament through the oviduct canal, where they attained the lumen of blood and lymphatic vessels, mainly of the vascular subovarian (VSP) and paraovarian lymphatic plexus (PLP), via the lymphatic stomata pathway. Transport of microspheres also took place simultaneously through the uterine and oviduct walls and from particular organs through blood and lymphatic vessels. Although the present results do not exclude the participation of countercurrent transfer between venous, lymphatic, and arterial vessels, they provide morphological evidence for the presence of direct transportation pathways of substances, released into the uterine lumen, into ovarian tissues through the oviduct canal.     

Basic mechanisms controlling lymph transport in the mesenteric lymphatic net

This minireview summarizes an oral presentation given at the National Institute of Diabetes and Digestive and Kidney Diseases National Institutes of Health workshop "Lymphatics in the Digestive System: Physiology, Health, and Disease" in Bethesda, Maryland on November 3-4, 2009. The concepts of extrinsic and intrinsic pumps, as well as intrinsic and extrinsic flows, are discussed in relation to the lymph transport in mesenteric lymphatic vessels. Age-related alterations in the structure and regulatory mechanisms of lymph flow in mesenteric lymphatic vessels may provide the basis for their diminished ability to work during the periods of increased functional loads in them. The recent development of modern experimental tools provides the opportunity to extend the knowledge on lymph transport function of lymphatic vessels that is absolutely necessary to maintain fluid and macromolecular homeostasis and to provide a transportation route for lipids adsorbed in gut and to immune cells.