Growth of the jugular lymph sacs and establishment of the topography of the cervical portion of the thoracic duct during early human ontogenesis

In 196 human embryos, prefetuses, fetuses and newborns, by means of a complex of morphological methods, development of the jugular lymphatic sacs and the process of settling of the thoracic duct cervical part topography have been studied. The jugular lymphatic sac anlages take place on the 6th week of the development. From the lymphatic cleft, situating in the mesenchyme near the anterior cardinal veins, multichambered cavities laid with endotheliocytes are forming,--the jugular lymphatic sacs. Connection of the initially close lymphatic sacs with the venous system takes place secondarily by the end of the embryonic period of development. In the area of the sac ostia a valve is formed, that makes morphological premises for unidirected lymph flow into the venous system. The lymph nodes developing at the place of the reducing jugular lymphatic sacs, ensure formation: from the left jugular lymphatic sac--the cervical part of the thoracic duct, from the right jugular lymphatic sac--the right lymphatic duct and the jugular and the subclavicular lymphatic trunks. Variability in the form and topography of these structures are determined both by the form and construction of the jugular lymphatic sacs and by developmental peculiarities of the lymph nodes at their place. The process of settling of the thoracic duct cervical part topography depends on age changes of its size and form, as well as on development of structures situating nearby, and by the time of birth it is not completed.     

Development of the thoracic duct in the prenatal period of human ontogeny

In 40 series of histological sections performed in human embryos and prefetuses from 4 up to 20 weeks of development, as well as in 20 corpses of fetuses and stillborns, it has been stated that the anlage of the thoracic duct appear in 6-7-week-old fetuses as lymphatic clefts surrounded with mesenchymal cells that are situated near large veins in the areas of the most active morphogenesis. Connecting with each other, the clefts form the jugular and retroperitoneal lymph sacs and a well branching network of canals. From the latter, on the 7th-8th week of development a plexus of lymph vessels appear, and later on (on the 8th-9th week)--bilaterally situating trunks of the thoracic duct. Further development of the thoracic duct is connected with the lymph nodes formation, their germs appear on the 9th-10th week along the course of the left trunk, as well as along the ductal branches and anastomoses. The formation of the lymph nodes results in reduction of some trunks and plexuses of the thoracic duct. Owing to this, its form in 14-15-week-old prefetuses resembles the one in newborns. Disturbances in the formation processes of the lymph nodes along the course of the reducing ductal areas, as well as their formation along the course of its main trunk can result in various structural variants of the thoracic duct in children and grown-up persons. Histogenesis of the thoracic duct wall and formation of the lymph nodes are not completed by birth.     

The regulation of water-salt exchange in a disorder of the integrity of the lymph circulation system]

The mechanisms regulating the water-salt metabolism have been investigated in the experiment on dogs with a disturbance of the lymph flow system. The function of a regulator of the water-salt metabolism is found to be peculiar to the lymphatic system which is effected by means of the humoral properties of the lymph and discreteness of its static pressure in the thoracic lymphatic duct. The central lymph exerts a stabilizing effect on both the osmo- and volumoregulatory functions of the kidneys, cardio- and hemodynamics. The state of acute lymphohypertension in the system of the thoracic lymphatic duct activates the mechanisms of the water-salt metabolism aimed at decreasing the volume of the extracellular fluid.     

The volume rate of lymph flow in dogs in postnatal ontogeny

In experiments on 1-day to 3-month-old puppies and adult dogs, studies have been made on the lymph flow from the thoracic duct. Within the first week of postnatal life, the lymph volume was found to be high decreasing gradually in further development. In adult dogs, the volume of the lymph flowing from the thoracic duct per unit of time and per body mass was 3 times lower than that in 1-week-old puppies. Possible mechanisms of these differences are discussed.     

Roentgenologic investigation of collateral lymphatic pathways after ligation of the thoracic duct

In 80 Wistar rats by means of electroroentgenolymphography lymphatic pathways and thoracic duct have been studied, normal and after ligation of the latter in 1-3 days, 1 and 2-3 months. Contrasting of the thoracic duct in the control animals reveals its additional ducts, that run in parallel to the main collector and they get into it after a certain distance, as well as different time phases of filling the duct are noted. When the thoracic duct is ligated, in 1-3 days dilatation of the ductal cistern, contrasting of lymphatic vessels and nodes in other regions are observed. In 1 month of the experiment the thoracic duct cistern is poorly expressed in comparison with the early time. The contrast substance continues to get into the group of the lymph nodes in other regions. A network of anastomoses of lymphatic vessels is formed in the area of ligation. In 2-3 months, when the contrast substance continues to get retrogradely into other groups and regions of the lymph nodes, final restoration of the lymph-flow takes place at the expense of formation of collateral pathways.     

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.     

Inability of large granular lymphocytes to recirculate through blood-lymph barriers

The level of large granular lymphocytes (LGL) has been determined in thoracic lymph duct and peripheral blood of cattle. It has been shown that in contrast to the blood, these cells are present in the lymph in minor quantities. Unlike blood LGL, lymph LGL have smaller granules in cytoplasm. It is concluded that LGL do not recirculate from blood to central lymph.     

Changes in thoracic and right duct lymph flow and enzyme content during skeletal muscle stimulation.

In the pentobarbital-anaesthetized dog the effect of electrical stimulation of hindlimb skeletal muscles on thoracic and right duct lymph flow and enzyme content was examined. Increase in plasma creatine kinase (CK), L-aspartate-aminotransferase (AST) and lactic dehydrogenase (LDH) during 30-min muscle stimulation were not significantly altered by draining lymph. Both right duct and thoracic duct lymph flow trebled during stimulation. At the same time, the activity of the three enzymes examined decreased in right duct lymph and increased in thoracic duct lymph. Of the latter, only the increase in lymph CK was of a sufficient magnitude to have resulted in a detectable increase in plasma CK. CK was the smallest of the three enzymes studied and apparently preferentially entered the lymph, suggesting that the larger AST and LDH molecules were not likely to have entered the blood plasma directly from skeletal muscle. Rather their entry from some other tissue, possibly the formed elements of the blood, is indicated.     

Applied aspects of anatomy of the lumbar lymph nodes and their vessels

Using anatomical and roentgenoanatomical methods in 132 corpses of persons (from newborns up to 83 years of age) the anatomy of the lumbar lymph nodes and their vessels has been studied. Their topography, skeletotopy , amount, dimensions and form have been determined. Afferent and deferent lymphatic vessels in various groups of the lumbar lymph nodes, collateral pathways of lymph outflow to by-pass the lumbar lymph nodes are described. Certain data on the types of the thoracic duct formation are presented.     

Surgical techniques for long-term studies of thoracic duct circulation in the rat.

Two techniques for cannulation of the thoracic duct in the rat, thoracic duct shunt and thoracic duct side fistula, are described. They give access, for repetitive sampling, to a normal thoracic duct circulation and are suited for study of the circulation under physiologic conditions. The thoracic duct shunt creates, with tubing, a shunt between the caudad and cephalad ends to the cisterna chyli. The exteriorized midportion of the shunt allows observation of the lymph. In the thoracic duct side fistula, the short arm of a T tube is placed within the cisterna and sampling is done via the long arm of the tube. Ten shunts functioned for 8-26 days and 10 side fistulas functioned for 8-30 days. Average lymph flow was 0.044 ml/min (shunts) and 0.042 ml/min (side fistulas). Average thoracic duct lymphocyte output was 1,729,000 cells/min (shunts) and 2,310,000 cells/min (side fistulas). Average blood lymphocyte count was 11,700 cells/mm3 (shunts) and 12,600 cells/mm3 (side fistulas). All parameters remained stable during the period of study. Advantages of those techniques over the Bollman end fistula are presented.     

Adrenergic innervation of lymph nodes and the thoracic duct

By means of incubation of slices in 2% solution of glyoxylic acid distribution of adrenergic fibers in the rabbit lymph nodes and in the thoracic lymphatic duct has been studied. Adrenergic fibers get into parenchyma of the lymph nodes via two ways. The first--the perivascular, when the nervous fibers make a plexus and get into the node along the blood vessels, the second--diffuse nervous fibers get together with trabecules in between the lymphoid nodules. The distribution density of the adrenergic fibers is not the same in different groups of the lymph nodes. In the lumbar nodes it is the highest. In the lymph nodes of the cervical part the density of the sympathetic fibers is, as a rule, lower than in the lumbar, but higher than in the axillary nodes. The lowest density of th adrenergic fibers is in the mesenteric, superficial inguinal lymph nodes and in the lymph nodes, situating near the thoracic part of the aorta. In the lymphatic duct wall small amount of adrenergic fibers are revealed, they form a plexus, predominantly in the cranial part.     

Antigenic relationship between medullary thymocytes and a subpopulation of peripheral T cells in the rat: description of a masked antigen.

Using differentially absorbed rabbit antisera to rat thoracic duct cells, an antigen is described which normally is expressed on the surface of T cells in thoracic duct lymph and lymph node, but which exists in a masked form on medullary thymocytes and apparently not at all on cortical thymocytes. This antigen is termed the rat masked thymocyte antigen (RMTA). RMTA on medullary thymocytes can be unmasked mechanically by sectioning in a cryostat or enzymatically by treating with neuraminidase. Trypsin destroys or removes RMTA. Nearly all the T cells in thoracic duct lymph and lymph node are RMTA⁺, whereas only 58–66% of T cells in spleen are RMTA⁺. RMTA⁺ T cells, which are cortisone resistant, reside in the paracortex and periarteriolar sheath regions of lymph node and spleen. RMTA^? T cells, which are cortisone sensitive, appear to reside in the red pulp of spleen. The results suggest that (i) two antigenically distinct populations of T cells exist in the rat, RMTA⁺ and RMTA^? T cells, (ii) medullary thymocytes are the immediate precursors of RMTA⁺ T cells, and (iii) cortical thymocytes may be the immediate precursors of RMTA^? cells.     

Mechanical characteristics of the canine thoracic duct: what are the driving forces of the lymph flow?

This study is designed to better understand the mode of lymph transport, particularly through the extrinsic pumping by external compression of the lymph vessel. The pressure-diameter relationship of lymphatic segments isolated from the canine thoracic duct was examined using a laser optical micrometer measurement system. Results revealed that the thoracic duct displayed a high extensibility or compliance in the physiological pressure range, yet became progressively less so with increasing internal pressure. The calculated incremental circumferential modulus of the thoracic duct under physiological pressure (range of 2 to 6 cm H2O) showed values ranging from 1.2 x 10(4) to 3.61 x 10(5) dyn/cm2. At a pressure of 35 cm H2O, the modulus reached a limiting value of approximately 6.0 x 10(6) dyn/cm2. In the physiological pressure range, the relative wall thickness (h/R0) of the canine thoracic duct was approximately 3.5%, which was much lower than that reported for canine arterial segments and similar in value to that of the canine jugular vein. In conclusion, the pressure-diameter curve of the canine thoracic duct was shown to resemble that of venous vessels. However, the circumferential elastic modulus of the thoracic duct wall was lower than the moduli of veins, proving that lymphatics are more compliant than veins. This suggests lymph flow in the thoracic duct may be better promoted by external compression of the lymphatic vessel.     

Amino acid composition of the lymph and blood in fever reactions of different durations

The amino acid composition of the thoracic duct lymph and blood following fever reactions (FR) of various duration has been studied in the experiments on rabbits. The experiments have shown that some changes in protein metabolism in FR are primarily manifested in amino acid lymph composition. Irrespective of FR duration the amino acid content in the lymph almost always increases, which confirms the opinion concerning catabolic process predominance in protein metabolism during FR. The lack of "cumulative" conditions in the blood, amino acid dilution in the large volume of the circulating blood, as well as the increase of vascular permeability during FR cause less marked increase in amino acid content in the blood than in the lymph.     

Reaction of human lymphocytes with aggregated IgG columns. Effect on antibody-dependent cytotoxicity and EAC rosette formation.

The origin and life span of long-lived small lymphocytes in the bone marrow of mice have been evaluated by the use of radioautography, scintillation counting, and anti-theta serum. Thymus-deprived BALB/C mice and nude mice had a smaller percentage of long-lived lymphocytes in bone marrow and in thoracic duct lymph than sham-operated or normal littermates. Furthermore, the long-lived lymphocytes in the marrow of nudes have more varied—but generally shorter—life spans than long-lived lymphocytes from mice having a thymus. In thoracic duct lymph of nude mice a more homogeneous long-lived population—according to life span—was found.It was concluded that both long-lived T cells and long-lived B cells are normal residents in the bone marrow. Furthermore, it was concluded that cells of variable life spans comprise the B lymphocyte population: short-lived cells with life spans of 3–5 days and long-lived lymphocytes with life spans of weeks to months.     

Serum and lymph lipids in rabbits with carbon tetrachloride-induced cirrhosis of the liver

Lymph flow and the composition of lymph lipids from the hepatic and thoracic ducts of rabbits with cirrhosis of the liver (induced by 46-51 intramuscular injections of a mixture of carbon tetrachloride and olive oil at 4-day intervals) have been compared with those of control animals injected with olive oil only. In cirrhotic animals, the concentration of lymph lipids was not greatly altered, but lymph flow, and consequently the hourly transport of lipids by lymph were greatly increased; the increase in transport of cholesteryl esters, free cholesterol, and phospholipids by way of the thoracic and hepatic duct lymph was particularly striking. The concentration of these lipid fractions in serum from the cirrhotic rabbits was also increased. The differences normally observed between lipid fatty acid compositions of serum and lymph disappeared in cirrhotic animals; this is interpreted as due to increased hepatic permeability to lipoproteins.     

Effect of the fever reaction on the kallikrein-kinin system of the lymph and blood

The dynamics of kallikrein-kinin system components in the lymph of thoracic duct and blood following fever reaction of various duration has been studied in the experiment on rabbits. The experiments have shown that in prolonged fever reaction there are qualitative disorders in kinin system components ratio indicative of break in the system of regulatory links, its exhaustion and transformation of the physiological reactions into the pathogenic ones. One may assume that changes in kallikrein-kinin system activity in body fluid are the links in the complex of pathogenic disorders in the organ and system functional activity during prolonged fever reaction.     

Extra-organic lymphatic vessels and regional lymph nodes of the kidneys in dogs

An anatomical investigation of extraorganic lymphatic vessels and regional renal lymph nodes has been performed in 70 dogs. The regional lymph nodes in the right kidney are stated to be quantitatively constant, as well as cranial and caudal lateroaortal lymph nodes in the left kidney in regard to the middle left lateroaortal nodes, that get lymph from the left kidney parenchyma. One middle left lateroaortal lymph node is found in 47 animals examined, two lymph nodes--in 17 animals. In 6 cases a lymphatic vessel, that gets lymph from the renal parenchyma and independently runs into the cistern of the thoracic duct is found for the first time. The variant revealed is an exception from the rule known in lymphology: lymph in its way from periphery to the central collector runs, at least, through one lymph node.     

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.     

Effect of rutin on the cholesterol content of the lymph, blood and tissues of the dog

It has been discovered in experiments on mongrel dogs anesthetized with morphine and hexenal that intravenous injection of rutin (3 mg/kg bw) reduced the concentration of total, esterified and free cholesterol in blood serum, with the exception of free cholesterol level in arterial blood, which increased. Under the same conditions, the concentration of free and esterified cholesterol in thoracic duct lymph ascended. In the popliteal lymph node, gastrocnemius muscle and liver, the content of total cholesterol appreciably dropped as compared to control. Rutin has been found to accelerate the lymph flow and to raise cholesterol resorption from the interstitial space. It is inferred that lymph plays an important part in cholesterol transport in the body.