PubMed Health⌕ Search

SEARCH · PubMed Health

Results for “LYMPHATIC VESSELS”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 163 records · Page 9Linked to original sources
PubMed1990

Enzyme-histochemical identification of lymphatic vessels by light and backscattered image scanning electron microscopy.

The walls of lymphatics are characterized by strong 5'-nucleotidase activity, whereas those of blood capillaries reveal significantly lower or no activity. Alkaline phosphatase activity, on the other hand, is markedly higher in blood capillaries than in lymphatic vessels. On the basis of such characteristics, lymphatics and blood capillaries were distinguished histochemically in rat stomach using 5'-nucleotidase-alkaline phosphatase double staining. The distribution and intensity of lead-demonstrated 5'-nucleotidase activity in lymphatic vessels could be determined by comparing the images of the same histochemically stained cryostat section as seen by light and backscattered image scanning electron microscopy. The specificity of the 5'-nucleotidase reaction was obtained by inhibiting nonspecific alkaline phosphatase by including L-tetramisole in the 5'-nucleotidase incubation medium. The products of the 5'-nucleotidase activity were deposited on the outer surface of the plasma membrane of the lymphatic endothelial cells.

5'-Nucleotidase↗
PubMed2007

Tumor cell transendothelial passage in the absorbing lymphatic vessel of transgenic adenocarcinoma mouse prostate.

The distribution and fine structure of the tumor-associated absorbing lymphatic vessel in the tumor mass of prostate adenocarcinoma and of seminal vesicle metastasis in transgenic mice was studied for the purpose of understanding the modality of tumor cell transendothelial passage from the extravasal matrix into the lymphatic vessel. In the tumor mass, two main cell populations were identified: stromal tumor cells and the invasive phenotype tumor (IPT) cells, having characteristics such as a highly electron-dense matrix rich in small granules lacking a dense core and massed nuclear chromatin, which is positive to immunostaining with anti-SV40 large T antigen antibody. Based on the ultrastructural pictures of different moments of the IPT cell transendothelial passage by ultrathin serial sections of the tumor-associated absorbing lymphatic vessel, the manner of its transendothelial passage through the intraendothelial channel, without involving intercellular contacts, was demonstrated. The presence of IPT cells in the parenchyma of satellite lymph node highlights its significant role in metastatic diffusion. The intraendothelial channel is the reply to the lack of knowledge regarding the intravasation of the tumor cell into the lymphatic circulation. The lymphatic endothelium would organize this channel on the basis of tumor cell-endothelial cell-extravasal matrix molecular interactions, which are as yet unidentified.

Adenocarcinoma↗
PubMed1995

Relation of granulomas to lymphatic vessels in Crohn's disease.

AIMS: To examine the relation between granulomas and lymphatic vessels in Crohn's disease. METHODS: Formalin fixed, paraffin wax embedded sections were selected from surgical resection specimens from 10 cases diagnosed as Crohn's disease. The block that showed the most granulomas was selected from each case. Sections 5 microns thick were immunostained with antibodies directed against the endothelial markers factor VIII related antigen and Ulex europaeus lectin, and against the vascular wall components collagen IV and laminin. Granulomas were counted on each slide in the serosa, muscularis propria, submucosa, and mucosa. In each area granulomas were classified according to their relation to lymphatic or blood vessels. RESULTS: Overall, an average of 46.1% of granulomas (range 15.3-90.4%) was related to lymphatic vessels, with the majority of these being adjacent to the vessel, rather than in the lumen or distorting the wall. A smaller percentage (10.1%, range 2.4-25.8%) was related to blood vessels. CONCLUSIONS: A significant proportion of granulomas in Crohn's disease is associated with lymphatic vessels. Blood vessel involvement may be a secondary phenomenon, rather than the primary event.

Antigens↗
PubMed1990

Deep splenic lymphatic vessels in the mouse: a route of splenic exit for recirculating lymphocytes.

A study of pathways of lymphocyte migration through mouse spleen revealed lymphatic channels closely following arteries in trabeculae and white pulp. Because there is no detailed record of the layout of deep splenic lymphatics in the mouse, or other species, we present our observations in this paper, relating our findings to normal migratory pathways of lymphocytes through the spleen. Lymphatics draining the spleen are so inconspicuous that they often are not mentioned in anatomical discussions. The data presented clearly demonstrate 1) the existence and layout of deep lymphatic vessels in the mouse spleen, and 2) that migrating lymphocytes exit white pulp via these lymphatic vessels. CD4+ and CD8+ T cell subsets migrated proximally along the central artery from distal (dPALS) to proximal periarterial lymphatic sheaths (pPALS) and exited via deep lymphatic vessels that originate there. B cells migrated from dPALS to enter lymphatic nodules (NOD), thus segregated from T cells. B cells then migrated toward and exited via deep lymphatics. The appearance of labelled lymphocytes in lymph coincided with their disappearance from white pulp compartments. Labelled T cells were observed in splenic lymphatics as early as 1 hr after intravenous infusion but took, on average, about 6 hr. B cells took somewhat longer. Thus T and B cells entered and left white pulp through shared pathways, but took divergent intermediate routes through dedicated zones, pPALS for T cells, NOD for B cells.

Animals↗
PubMed2006

Development of cerebrospinal fluid absorption sites in the pig and rat: connections between the subarachnoid space and lymphatic vessels in the olfactory turbinates.

The textbook view that cerebrospinal fluid (CSF) absorption occurs mainly through the arachnoid granulations and villi is being challenged by quantitative and qualitative studies that support a major role for the lymphatic circulation in CSF transport. There are many potential sites at which lymphatics may gain access to CSF but the primary pathway involves the movement of CSF through the cribriform plate foramina in association with the olfactory nerves. Lymphatics encircle the nerve trunks on the extracranial surface of the cribriform plate and absorb CSF. However, the time during development in which the CSF compartment and extracranial lymphatic vessels connect anatomically is unclear. In this report, CSF-lymphatic connections were investigated using the silastic material Microfil and a soluble Evan's blue-protein complex in two species; one in which significant CSF synthesis by the choroid plexus begins before birth (pigs) and one in which CSF secretion is markedly up regulated within the first weeks after birth (rats). We examined a total of 46 pig fetuses at embryonic (E) day E80-81, E92, E101, E110 (birth at 114 days). In rats, we investigated a total of 115 animals at E21 (birth at 21 days), postnatal (P) day P1-P9, P12, P13, P15, P22, and adults. In pigs, CSF-lymphatic connections were observed in the prenatal period as early as E92. Before this time (E80-81 fetuses) CSF-lymphatic connections did not appear to exist. In rats, these associations were not obvious until about a week after birth. These data suggest that the ability of extracranial lymphatic vessels to absorb CSF develops around the time that significant volumes of CSF are being produced by the choroid plexus and further support an important role for lymphatic vessels in CSF transport.

Animals↗
PubMed2004

Lymphatic vessels gain access to cerebrospinal fluid through unique association with olfactory nerves.

BACKGROUND: Physiological studies suggest that a major portion of cerebrospinal fluid (CSF) drainage is associated with transport along cranial and spinal nerves with absorption taking place into lymphatic vessels external to the central nervous system. Especially important is CSF transport through the cribriform plate in association with the olfactory nerves. This study examined the anatomical connections that link the CSF and extracranial lymphatics at the base of the brain. METHODS AND RESULTS: The contrast agent, Yellow Microfil, was infused into the cranial sub-arachnoid compartment of 2- to 7-day-old lambs postmortem. In some animals, blue Microfil was perfused into the carotid arteries. Yellow Microfil was observed in extensive lymphatic networks in the submucosa associated with the olfactory and respiratory epithelium. Since little of the contrast agent was present within the interstitium of the olfactory submucosa, there appeared to be direct continuity between the subarachnoid space, the perineurial spaces of the olfactory nerve fibers that penetrated the cribriform plate, and the lumens of the lymphatic vessels within the olfactory submucosa. Lymphatics encircled the olfactory nerves at the level of the emerging nerve rootlets (in many cases providing the outer limit of the perineurial space) and then dispersed freely in the submucosa at greater distance from the crib-riform plate. These vessels converged into larger collecting ducts that emptied into various lymph nodes in the head and neck. CONCLUSIONS: Lymphatic vessels gain access to the brain extracellular fluid (CSF) in an unusual anatomical association with the olfactory nerves external to the cranial vault. This study highlights the important role played by lymphatic vessels in CSF absorption.

Animals↗
PubMed1983

Suppression of lymphatic vessel contractility with inhibitors of arachidonic acid metabolism.

Contractions of lymphatic vessels play an important role in regulating lymph flow; however, little is known of the pharmacological properties of these vessels and the mechanisms regulating the contractions. Earlier work had suggested that arachidonic acid metabolites may play some role in the contractile process and in this report we have assessed the effects of various inhibitors of arachidonate metabolism on the contractions of bovine mesenteric lymphatic rings suspended in tissue baths. Aspirin and indomethacin (cyclooxygenase inhibitors), BW 755C (a cyclooxygenase and lipoxygenase inhibitor) and FPL 55712 (a slow reacting substance of anaphylaxis-leukotriene-antagonist) suppressed the phasic contractions of spontaneously active vessels. The addition of arachidonate to noncontracting vessels elicited phasic and tonic contractile activities which were similarly blocked with these drugs, as were the contractions elicited with several agonists. These results suggest that lymphatic vessel contractions are extremely susceptible to suppression with inhibitors of arachidonate metabolism implying that these drugs may alter extravascular fluid dynamics by a direct effect on the lymphatic vessel. The intrinsic contractile regulatory mechanism may involve the production of arachidonate products within the vessel.

15-Hydroxy-11 alpha,9 alpha-(epoxymethano)prosta-5↗
PubMed2001

The use of isosulphan blue to identify lymphatic vessels in high retroperitoneal ligation of adolescent varicocele--avoiding postoperative hydrocele.

OBJECTIVE: To assess whether identifying and preserving the lymphatic vessels, using vital dyes, avoids postoperative hydrocele in adolescents with varicocele undergoing high retroperitoneal ligation (Palomo procedure). PATIENTS AND METHODS: The results were assessed from 28 consecutive adolescent patients undergoing varicocelectomy, treated between 1998 and 1999 by the Palomo procedure. The lymphatic vessels were identified and preserved using vital dyes, to avoid postoperative hydrocele formation. RESULTS: In 24 of the 28 patients (86%) the identification and preservation of lymphatic vessels was feasible. Over a mean (range) follow-up of 14 (4-24) months there were no postoperative hydroceles and no clinical recurrences. CONCLUSION: Identifying and preserving the lymphatic drainage of the testis and tunica vaginalis using vital dyes prevents the development of postoperative hydrocele in adolescents undergoing the Palomo procedure.

Adolescent↗
PubMed2005

[Clinicopathological study of lymphatic vessel density and distribution in pancreatic cancer].

OBJECTIVE: To clarify the clinicopathological significance of lymphatic vessel density (LVD) and distribution in pancreatic cancer. METHODS: We measured LVD in 43 pancreatic cancer specimens by immunostaining with specific lymphatic endothelium marker, and examined their relationship with well-defined clinicopathological variables. RESULTS: Intratumoral LVD (9.4 +/- 10.0) was significantly lower than periturmoral (16.0 +/- 9.7) (P < 0.001) and nontumoral LVD (13.5 +/- 6.0) (P < 0.01). Increased peritumoral LVD correlated significantly with tumor staging (P < 0.05) and lymph node involvement (P < 0.05). CONCLUSION: The lymphatic vessels distribution in pancreatic cancer samples and peritumoral lymphangiogenesis may promote the malignant progression and lymph node metastasis of pancreatic cancer.

Adenocarcinoma↗
PubMedDate not supplied

[Electrophysiological properties of the membrane of smooth muscle cells from bovine lymphatic vessels].

Using single sucrose gap technique, studies have been made on electrophysiological properties of the membrane in myocytes of the lymphatic vessels in the ox Bos taurus. It was shown that electrical stimulation does not induce tetanic contraction in the myocytes. The results obtained indicate strong similarity between electrophysiological properties of the myocytes in the lymphatic vessels and those of the myocardial cells in homoiotherms. Refractory state which follows the action potential, accounts for a possibility of rhythmic activity in the myocytes of the lymphatic vessels. Both single and rhythmic stimulation produce in the myocytes the "all-or-none" response. The main factor determining the level of excitability in the myocytes is the intravascular pressure. The latter exerts its influence on contractile activity via changes in the electrical activity (the membrane potential, duration of the plateau phase and the number of fast peak potentials on this plateau).

Action Potentials↗
PubMed1996

Weibel-Palade bodies and lymphatic endothelium: observations in the lymphatic vessels of normal and inflamed human dental pulps.

The Weibel-Palade bodies, cytoplasmic organelles characterizing endothelial cells, are abundant in lymphatic capillary endothelium of human dental pulp. Their number almost double in the lymphatic vessels of inflamed dental pulps. The data were discussed and compared with others concerning the demonstration of the presence of von Willebrand factor and P-selectin in the Weibel-Palade bodies of lymphatic vessels in mesentery. It is suggested that the increase in the number of Weibel-Palade bodies observed in dental pulp may be connected along with those in the lymphatic vessels to the function that these adhesive molecules play during inflammatory states.

Dental Pulp↗
PubMed2006

Lymphatic vessels in cancer metastasis: bridging the gaps.

Distant organ metastasis is the most important factor in determining patient survival in cancer. This is thought to occur via the body's own systems for transporting fluid and cells, the blood vascular and lymphatic systems. Cancer cells may exploit these vascular systems by expressing growth factors, which alter the normal pattern of angiogenesis and lymphatic vessel growth (lymphangiogenesis), thus creating conduits for tumour metastasis. With respect to lymphatic metastasis, techniques which allow the mapping of a tumour's lymphatic drainage and sampling of the 'sentinel node' from the regional lymph node group provide crucial prognostic information, determine further treatment and offer a window into tumour-host immune interactions. Aberrant drainage patterns so identified are both clinically significant, and highlight important anatomical and molecular complexities not explained by existing models of lymphatic development or anatomy. The molecular controls of tumour lymphangiogenesis and factors determining which lymphatic vessel subtypes are induced may be targets for novel therapeutics designed to restrict cancer metastasis. Furthermore, analyses of these control mechanisms will enhance our understanding of the interactions between the tumour cells and the lymphatic vasculature. For many years, disparate groups of clinical researchers and basic scientists have been working to unravel the mysteries of the lymphatic system. This review aims to summarize these contributions, in terms of the history, identification, structure and function of lymphatic vessels in cancer and the role they play in tumour metastasis. Current ideas about the roles of lymphangiogenic growth factors, their signalling pathways in lymphatic metastasis and therapeutic opportunities to restrict this spread will also be explored.

Animals↗
PubMed2004

Effect of acute hypoxia in pregnant females on contractile activity of lymphatic vessels in the offspring.

Delayed consequences of acute hypoxia were studied in 60-day-old rat pups. The animals were exposed to acute hypobaric hypoxia on day 10 of embryogenesis. The offspring of intact females served as the control. Reactivity of mesenteric lymphatic vessels to norepinephrine was studied by vital microscopy. The frequency and duration of lymphatic vessel contractions in males significantly increased compared to the control. In females the duration of norepinephrine-induced lymphatic vessel contractions increased, while the frequency and amplitude of contractions and basal vascular tone did not differ from the control.

Animals↗
PubMed2004

[Role of adrenoreceptors in the effect of thyroliberin on lymphatic vessels].

Formerly we showed that TRH had simulative effect on mesenteric bovine and rat lymphatic vessels (LV) in very low concentration--10(-12)-10(-18) M. In present paper, participation of LV alpha- and beta-receptors in realization of TRH activity on rat mesenteric lymphatic vessels was studied in situ. Propranolol increased the stimulative effect of TRH, isoproterenol exerted an opposite effect. Phentolamine, prazosin eliminated the simulative effect of TRH, yohimbine resulted in additional gain of effect, which seems to testify 1) presynaptic action of TRH or 2) increase of the output of norepinephrine, which is potentiated by alpha 2-adrenoceptor antagonists. Also the participation of adrenergic receptors in positive chronotropic effects of mesenteric rat LV was studied using the method of selective destruction of dopamine-containing neurons after 6-OHDA infusion. As it occurred, desympathization hindered development of stimulating action of TRH. Thus, the efficiency of TRH as a stimulator of LV is connected with activation of adrenergic mechanisms.

Adrenergic Agonists↗
PubMed2006

Imaging of lymphatic vessels in breast cancer-related lymphedema: intradermal versus subcutaneous injection of 99mTc-immunoglobulin.

OBJECTIVE: The disordered physiology that results from axillary lymph node clearance surgery for breast cancer and that leads to breast cancer-related lymphedema is poorly understood. Rerouting of lymph around the axilla or through new pathways in the axilla may protect women from breast cancer-related lymphedema. The aim of the study was to compare intradermal with subcutaneous injection of technetium-99m ((99m)Tc)-labeled human polyclonal IgG (HIG) with respect to lymphatic vessel imaging. MATERIALS AND METHODS: Six women with breast cancer-related lymphedema underwent unilateral upper limb lymphoscintigraphy, using a web space injection of (99m)Tc-labeled HIG, after intradermal and subcutaneous injections on separate occasions. Multiple sequential images were obtained of the affected upper limb and torso over 3 hr on each occasion. Accumulation of activity in blood was quantified from venous blood samples taken from the opposite arm. RESULTS: Imaging after intradermal injection clearly showed discrete lymphatic vessels in five of six patients, in contrast to imaging after subcutaneous injection, which did not show any discrete vessels in any patient. Intradermal injection resulted in more rapid visualization of cutaneous lymph rerouting than subcutaneous injection in six of six patients. Recovery of injected (99m)Tc-labeled HIG in venous blood was greater after intradermal injection in six of six patients. CONCLUSION: In patients with breast cancer-related lymphedema, lymphatic vessels are more clearly depicted after intradermal than subcutaneous injection as a result of direct access of radiotracer to dermal lymphatics. This finding has implications for imaging lymphatic vessel regeneration and lymph rerouting.

Adult↗
PubMed1997

Fine structure and distribution of lymphatic vessels in the human dental pulp: a study using an enzyme-histochemical method.

The existence of lymphatic vessels in the human dental pulp and their distribution were established by light and electron microscopy using an enzyme-histochemical method. The distinction between lymphatic and blood vessels was made by light microscopy on cryostat sections of undecalcified and decalcified teeth using 5'-nucleotidase(5'-Nase)-alkaline phosphatase double staining. On the tissue surface, 5'-Nase-positive lymphatic vessels were highlighted with good contrast and resolution by backscattered electron imaging using scanning electron microscopy. By transmission electron microscopy, dense granular precipitations resulting from the 5'-Nase reaction were seen on the luminal surface of the lymphatic endothelial cells as well as in the area at the basal side, but were absent in the blood vessels. These lymphatic vessels were more numerous in the central part than in the peripheral odontoblastic layer.

5'-Nucleotidase↗