Physiotherapeutic rehabilitation of lymphedema: state-of-the-art.

Lymphatic diseases, especially lymphedema, represent a serious problem in the health community. We investigated strategies and methods for physiotherapeutic rehabilitation of lymphedema by carrying out a comprehensive search of the Medline and Embase databases from 1990 to 2016 to identify relevant published studies, articles, and reviews. Approaches for conservative management of lymphedema include the following: manual lymphatic drainage, lymphedema rehabilitation exercises, compression therapy, skin care, pneumatic compression, elevation of the extremities, thermal therapy, complete decongestive physiotherapy (CDT), taping, and aqua lymphatic therapy. Treatment of lymphedema with CDT, which is a combination of four methods (manual lymphatic drainage, lymphedema rehabilitation exercises, compression therapy, skin care), can achieve a 45-70% reduction in lymphedema volume. Prerequisites for successful physiotherapy are the availability of physicians, nurses and therapists who are specifically trained, educated, and experienced in each method. CDT is the most effective treatment as it reduces the symptoms of lymphedema and improves patients' functionality, mobility, and quality of life. Although other therapeutic techniques have demonstrated positive results, these surveys are limited and more studies are needed to confirm findings.

Lymphatic Pump Treatment Mobilizes Bioactive Lymph That Suppresses Macrophage Activity In Vitro.

CONTEXT: By promoting the recirculation of tissue fluid, the lymphatic system preserves tissue health, aids in the absorption of gastrointestinal lipids, and supports immune surveillance. Failure of the lymphatic system has been implicated in the pathogenesis of several infectious and inflammatory diseases. Thus, interventions that enhance lymphatic circulation, such as osteopathic lymphatic pump treatment (LPT), should aid in the management of these diseases. OBJECTIVE: To determine whether thoracic duct lymph (TDL) mobilized during LPT would alter the function of macrophages in vitro. METHODS: The thoracic ducts of 6 mongrel dogs were cannulated, and TDL samples were collected before (baseline), during, and 10 minutes after LPT. Thoracic duct lymph flow was measured, and TDL samples were analyzed for protein concentration. To measure the effect of TDL on macrophage activity, RAW 264.7 macrophages were cultured for 1 hour to acclimate. After 1 hour, cell-free TDL collected at baseline, during LPT, and after TDL was added at 5% total volume per well and co-cultured with or without 500 ng per well of lipopolysaccharide (LPS) for 24 hours. As a control for the addition of 5% TDL, macrophages were cultured with phosphate-buffered saline (PBS) at 5% total volume per well and co-cultured with or without 500 ng per well of LPS for 24 hours. After culture, cell-free supernatants were assayed for nitrite (NO2-), tumor necrosis factor α (TNF-α) and interleukin 10 (IL-10). Macrophage viability was measured using flow cytometry. RESULTS: Lymphatic pump treatment significantly increased TDL flow and the flux of protein in TDL (P<.001). After culture, macrophage viability was approximately 90%. During activation with LPS, baseline TDL, TDL during LPT, and TDL after LPT significantly decreased the production of NO2-, TNF-α, and IL-10 by macrophages (P<.05). However, no significant differences were found in viability or the production of NO2-, TNF-α, or IL-10 between macrophages cultured with LPS plus TDL taken before, during, and after LPT (P>.05). CONCLUSION: The redistribution of protective lymph during LPT may provide scientific rationale for the clinical use of LPT to reduce inflammation and manage edema.

Hydrogen sulfide in posthemorrhagic shock mesenteric lymph drainage alleviates kidney injury in rats.

Posthemorrhagic shock mesenteric lymph (PHSML) is a key factor in multiple organ injury following hemorrhagic shock. We investigated the role of hydrogen sulfide (H2S) in PHSML drainage in alleviating acute kidney injury (AKI) by administering D,L-propargylglycine (PPG) and sodium hydrosulfide hydrate (NaHS) to 12 specific pathogen-free male Wistar rats with PHSML drainage. A hemorrhagic shock model was established in 4 experimental groups: shock, shock+drainage, shock+drainage+PPG (45 mg/kg, 0.5 h prehemorrhage), and shock+drainage+NaHS (28 µmol/kg, 0.5 h prehemorrhage). Fluid resuscitation was performed after 1 h of hypotension, and PHMSL was drained in the last three groups for 3 h after resuscitation. Renal function and histomorphology were assessed along with levels of H2S, cystathionine-γ-lyase (CSE), Toll-like receptor 4 (TLR4), interleukin (IL)-10, IL-12, and tumor necrosis factor (TNF)-α in renal tissue. Hemorrhagic shock induced AKI with increased urea and creatinine levels in plasma and higher H2S, CSE, TLR4, IL-10, IL-12, and TNF-α levels in renal tissue. PHSML drainage significantly reduced urea, creatinine, H2S, CSE, and TNF-α but not TLR4, IL-10, or IL-12. PPG decreased creatinine, H2S, IL-10, and TNF-α levels, but this effect was reversed by NaHS administration. In conclusion, PHSML drainage alleviated AKI following hemorrhagic shock by preventing increases in H2S and H2S-mediated inflammation.

[Update on special surgical approaches in the therapy for lymphedemas]. / Die Vielfalt in der chirurgischen Therapie beim Lymphödem - was ist aktuell?

Despite recent medical progress primary and secondary lymphedemas still represent a therapeutic challenge and they often lead to a significant reduction in quality of life. Lymphedemas usually develop in the extremities, the male external genitals as well as the female breast as a consequence to the axial alignment of the lymphatic collectors. Early stages are characterized by an excess of lymph fluid increasing the volume of the affected part of the body whereas later stages represent an increasing amount of solid tissue. Thus therapeutic efforts can focus on the reduction of the surplus of liquid and/or solid components. Generally there are conservative and operative strategies. Conservative measures mainly focus on the improvement of fluid mobilization and drainage and comprise compression garments, manual lymphatic drainage, and apparative intermittent compression. Operative approaches comprise procedures for surgical tissue reduction (symptomatic/ablative approaches) and/or procedures with the intention of enhancing lymphatic transport (causal approaches). Surgical tissue reduction can be performed by open resection and/or liposuction. Traditional surgical causal techniques such as transposition of local flaps aim at leading lymph away from the congested region of the body. Modern microsurgical causal approaches contain methods of reconstruction of interrupted lymphatic pathways as well as techniques for the conduction of lymph into local veins. In this review we depict and discuss the features of the multiform spectrum of the surgical therapy of lymphedemas on the basis of literature as well as our own clinical and experimental experience.

Chylomicron formation and secretion is required for lipid-stimulated release of incretins GLP-1 and GIP.

Glucagon-like peptide-1 (GLP-1) and glucose-dependent insulinotropic polypeptide (GIP) are incretins produced in the intestine that play a central role in glucose metabolism and insulin secretion. Circulating concentrations of GLP-1 and GIP are low and can be difficult to assay in rodents. These studies utilized the novel intestinal lymph fistula model we have established to investigate the mechanism of lipid-stimulated incretin secretion. Peak concentrations of GLP-1 and GIP following an enteral lipid stimulus (Liposyn) were significantly higher in intestinal lymph than portal venous plasma. To determine whether lipid-stimulated incretin secretion was related to chylomicron formation Pluronic L-81 (L-81), a surfactant inhibiting chylomicron synthesis, was given concurrently with Liposyn. The presence of L-81 almost completely abolished the increase in lymph triglyceride seen with Liposyn alone (P < 0.001). Inhibition of chylomicron formation with L-81 reduced GLP-1 secretion into lymph compared to Liposyn stimulation alone (P = 0.034). The effect of L-81 relative to Liposyn alone had an even greater effect on GIP secretion, which was completely abolished (P = 0.004). These findings of a dramatic effect of L-81 on lymph levels of GLP-1 and GIP support a strong link between intestinal lipid absorption and incretin secretion. The relative difference in the effect of L-81 on the two incretins provides further support that nutrient-stimulation of GIP and GLP-1 is via distinct mechanisms.

Pathways of lymph and tissue fluid flow during intermittent pneumatic massage of lower limbs with obstructive lymphedema.

Questions remain on the use of sequential pneumatic compression including where does the fluid flow to and whether fluid can be moved to the non-swollen tissues of the hypogastrium and gluteal region? During pneumatic massage of the limb, we studied pathways of lymph and mobile tissue fluid flow using lymphoscintigraphy: a) from the calf and thigh across the inguinal region to the healthy non-swollen tissues of the hypogastrium and b) in the hypogastrium to the lateral and upper abdominal quadrants. To examine if there was effective fluid flow during pneumatic massage, plethysmographic flow measurements were also carried out. We demonstrated that: (i) pneumatic compression moved isotope in lymph remaining in functioning lymphatics and in tissue fluid in the interstitial space toward the inguinal region and femoral channel, (ii) there was no isotope crossing the inguinal crease or moving to the gluteal area, and (iii) isotope injected intradermally in the hypogastrium did not spread during manual massage to the upper and contralateral abdominal quadrants. In conclusion, intermittent pneumatic compression is effective in pushing mobile tissue fluid and relocating large fluid volumes toward the groin. However, the question that still remains is how to facilitate further flow toward the non-swollen tissues and thereby increase local absorption of fluid.

Lymphatic pump treatment enhances the lymphatic and immune systems.

The osteopathic medical profession has long advocated the use of osteopathic lymphatic pump treatments (LPT) to improve lymphatic circulation, reduce edema and combat infectious disease. However, until recently, there was no scientific evidence that LPT enhances function of the lymphatic and immune systems. This review discusses the physiological functions of the lymphatic system, the ability of LPT to increase lymph flow under normal and experimental conditions, the clinical benefits of LPT, current research models for the study of LPT and the potential mechanisms by which LPT enhances lymphatic and immune function.

Lymphatic pump treatment increases thoracic duct lymph flow in conscious dogs with edema due to constriction of the inferior vena cava.

BACKGROUND: Osteopathic lymphatic pump treatments (LPT) are used to treat edema, but their direct effects on lymph flow have not been studied. In the current study, we examined the effects of LPT on lymph flow in the thoracic duct of instrumented conscious dogs in the presence of edema produced by constriction of the inferior vena cava (IVC). METHODS AND RESULTS: Six dogs were surgically instrumented with an ultrasonic flow transducer on the thoracic lymph duct and catheters in the descending thoracic aorta and in IVC. After postoperative recovery, lymph flow and hemodynamic variables were measured 1) pre-LPT, 2) during 4 min LPT, 3) post-LPT, in the absence and presence of edema produced by IVC constriction. This constriction increased abdominal girth from 60 +/-2.6 to 75 +/- 2.9 cm. Before IVC constriction, LPT increased lymph flow (P < 0.05) from 1.9 +/- 0.2 ml/min to a maximum of 4.7 +/-1.2 ml/min, whereas after IVC constriction, LPT increased lymph flow (P < 0.05) from 7.9 +/-2.2 to a maximum of 11.7 +/-2.2 ml/min. The incremental lymph flow mobilized by 4 min of LPT (ie, the flow that exceeded 4 min of baseline flow), was 10.6 ml after IVC constriction. This incremental flow was not significantly greater than that measured before IVC constriction. CONCLUSIONS: Edema caused by IVC constriction markedly increased lymph flow in the thoracic duct. LPT increased thoracic duct lymph flow before and after IVC constriction. The lymph flow mobilized by 4 min of LPT in presence of edema was not significantly greater than that mobilized prior to edema.

Lymphatic pump treatment mobilizes leukocytes from the gut associated lymphoid tissue into lymph.

BACKGROUND: Lymphatic pump techniques (LPT) are used clinically by osteopathic practitioners for the treatment of edema and infection; however, the mechanisms by which LPT enhances lymphatic circulation and provides protection during infection are not understood. Rhythmic compressions on the abdomen during LPT compress the abdominal area, including the gut-associated lymphoid tissues (GALT), which may facilitate the release of leukocytes from these tissues into the lymphatic circulation. This study is the first to document LPT-induced mobilization of leukocytes from the GALT into the lymphatic circulation. METHODS AND RESULTS: Catheters were inserted into either the thoracic or mesenteric lymph ducts of dogs. To determine if LPT enhanced the release of leukocytes from the mesenteric lymph nodes (MLN) into lymph, the MLN were fluorescently labeled in situ. Lymph was collected during 4 min pre-LPT, 4 min LPT, and 10 min following cessation of LPT. LPT significantly increased lymph flow and leukocytes in both mesenteric and thoracic duct lymph. LPT had no preferential effect on any specific leukocyte population, since neutrophil, monocyte, CD4+ T cell, CD8+ T cell, IgG+B cell, and IgA+B cell numbers were similarly increased. In addition, LPT significantly increased the mobilization of leukocytes from the MLN into lymph. Lymph flow and leukocyte counts fell following LPT treatment, indicating that the effects of LPT are transient. CONCLUSIONS: LPT mobilizes leukocytes from GALT, and these leukocytes are transported by the lymphatic circulation. This enhanced release of leukocytes from GALT may provide scientific rationale for the clinical use of LPT to improve immune function.

Hyperoxia increases the uptake of 5-fluorouracil in mammary tumors independently of changes in interstitial fluid pressure and tumor stroma.

BACKGROUND: Hypoxia is associated with increased resistance to chemo- and radiation-therapy. Hyperoxic treatment (hyperbaric oxygen) has previously been shown to potentiate the effect of some forms of chemotherapy, and this has been ascribed to enhanced cytotoxicity or neovascularisation. The aim of this study was to elucidate whether hyperoxia also enhances any actual uptake of 5FU (5-fluorouracil) into the tumor tissue and if this can be explained by changes in the interstitium and extracellular matrix. METHODS: One group of tumor bearing rats was exposed to repeated hyperbaric oxygen (HBO) treatment (2 bar, pO(2)= 2 bar, 4 exposures à 90 min), whereas one group was exposed to one single identical HBO treatment. Animals housed under normal atmosphere (1 bar, pO(2) = 0.2 bar) served as controls. Three doses of 5FU were tested for dose response. Uptake of [3H]-5FU in the tumor was assessed, with special reference to factors that might have contributed, such as interstitial fluid pressure (Pif), collagen content, oxygen stress (measured as malondialdehyd levels), lymphatics and transcapillary transport in the tumors. RESULTS: The uptake of the cytostatic agent increases immediately after a single HBO treatment (more than 50%), but not 24 hours after the last repeated HBO treatment. Thus, the uptake is most likely related to the transient increase in oxygenation in the tumor tissue. Factors like tumor Pif and collagen content, which decreased significantly in the tumor interstitium after repeated HBO treatment, was without effect on the drug uptake. CONCLUSION: We showed that hyperoxia increases the uptake of [3H]-5FU in DMBA-induced mammary tumors per se, independently of changes in Pif, oxygen stress, collagen fibril density, or transendothelial transport alone. The mechanism by which such an uptake occur is still not elucidated, but it is clearly stimulated by elevated pO(2).

Effects of manual lymph drainage on cardiac autonomic tone in healthy subjects.

This study was designed to investigate the effects of manual lymph drainage on the cardiac autonomic tone. Thirty-two healthy male subjects were randomly assigned to manual lymph drainage (MLD) (experimental) and rest (control) groups. Electrocardiogram (ECG) parameters were recorded with bipolar electrocardiography using standard limb lead positions. The pressure-pain threshold (PPT) was quantitatively measured using an algometer. Heart rate variability differed significantly between the experimental and control groups (p < 0.05), but the PPT in the upper trapezius muscle did not (p > 0.05). These findings indicate that the application of MLD was effective in reducing the activity of the sympathetic nervous system.

Trans-11 vaccenic acid reduces hepatic lipogenesis and chylomicron secretion in JCR:LA-cp rats.

Trans-11 vaccenic acid (VA) is the predominant trans isomer in ruminant fat and a major precursor to the endogenous synthesis of cis9,trans11-conjugated linoleic acid in humans and animals. We have previously shown that 3-wk VA supplementation has a triglyceride (TG)-lowering effect in a rat model of dyslipidemia, obesity, and metabolic syndrome (JCR:LA-cp rats). The objective of this study was to assess the chronic effect (16 wk) of VA on lipid homeostasis in both the liver and intestine in obese JCR:LA-cp rats. Plasma TG (P < 0.001), total cholesterol (P < 0.001), LDL cholesterol (P < 0.01), and nonesterified fatty acid concentrations, as well as the serum haptoglobin concentration, were all lower in obese rats fed the VA diet compared with obese controls (P < 0.05). In addition, there was a decrease in the postprandial plasma apolipoprotein (apo)B48 area under the curve (P < 0.05) for VA-treated obese rats compared with obese controls. The hepatic TG concentration and the relative abundance of fatty acid synthase and acetyl-CoA carboxylase proteins were all lower (P < 0.05) in the VA-treated group compared with obese controls. Following acute gastrointestinal infusion of a VA-triolein emulsion in obese rats that had been fed the control diet for 3 wk, the TG concentration was reduced by 40% (P < 0.05) and the number of chylomicron (CM) particles (apoB48) in nascent mesenteric lymph was reduced by 30% (P < 0.01) relative to rats infused with a triolein emulsion alone. In conclusion, chronic VA supplementation significantly improved dyslipidemia in both the food-deprived and postprandial state in JCR:LA-cp rats. The appreciable hypolipidemic benefits of VA may be attributed to a reduction in both intestinal CM and hepatic de novo lipogenesis pathways.

Drenaje linfatico manual, como parte del tratamiento en el síndrome del dolor regional complejo tipo I de extremidad superior / Manual lymphatic drainage in the treatment of complex regional pain syndrome type I of upper extremity

Síndrome de Dolor Regional Complejo Tipo -1 (SDRC- 1) constituye un conjunto de manifestaciones clínicas que se caracterizan, por dolor e impotencia funcional. Se relacionan con trastornos vasomotores intensos y prolongados, entre ellos edema y con alteraciones tróficas que afectan a parte o la totalidad de un miembro. El origen traumático es la causa más frecuente de SDRC - 1, aunque también puede desarrollarse a partir de una complicación iatrogénica de un tratamiento quirúrgico o médico. En el SDRC 1 se presenta un funcionamiento alterado del sistema nervioso simpático, lo cual produce una alteración vasomotora que contribuirá a la formación de un edema local de tipo mixto. El Drenaje Linfático Manual (Leduc) podría incorporarse dentro de un plan de tratamiento de esta patología. Con el DLM se pretende disminuir el edema, con lo que se atenuaría parte del dolor que presenta el paciente, ya que se lograría reducir, por un lado el estímulo mecánico que genera una presión anormal en los tejidos blandos de la extremidad afectada y el estímulo químico, causado por la acumulación de metabolitos en estos tejidos. Con esto se podría obtener mejores resultados en el tratamiento del SDRC 1.

The Complex Regional Pain Syndrome Tipe- I (SDRC-I) constitutes a set of clinical manifestations that are characterized, by pain and functional impotence. Theyare related to intense and prolonged vasomotors upheavals, among them edema and with trophics alterations that affect to a part or the totality of a member. The traumatic origin is the most frequent cause of SDRC- 1, although also can be developed from a iatrogenic complication of a surgical or medical treatment. In SDRC- I an altered operation of the likeable nervous system appears, which produces a vasomotor alteration that will contribute to the formation of a local edema of mixed type. The Manual Lymphatic Drainage (Leduc) could be gotten up within a plan of treatment of this pathology. With the DLM it is tried to diminish the edema, with which part of the pain that the patient presents would be attenuated, since it would be reduced, on one hand the mechanical stimulus that generates an abnormal pressure in soft weaves of the affected extremity and the chemical stimulus, caused by the accumulation of metabolitos in these weaves. With this it would be possible to obtain better results in the treatment of SDRC- 1.

Lymph flow in the thoracic duct of conscious dogs during lymphatic pump treatment, exercise, and expansion of extracellular fluid volume.

BACKGROUND: This investigation examined interactions between expansion of the extracellular fluid volume (ECE), osteopathic lymphatic pump treatment (LPT), and exercise on lymph flow in the thoracic duct of eight instrumented, conscious dogs. METHODS AND RESULTS: After recovery from surgery, LPT was performed for 8 min before and after ECE with normal saline, i.v., 4.4+/-0.3% of body weight. Baseline lymph flow was 1.7+/-0.5 mL/min. LPT rapidly increased lymph flow to 5.0+/-1.1 mL/min at 1 min, and lymph flow remained above baseline for 4 min (p<0.05). LPT produced a net increase in lymph flow of 15.4+/-1.1 mL. Following ECE, baseline lymph flow was 4.8+/-0.6 mL/min (p<0.05). LPT increased lymph flow to 9.9+/-1.1 mL/min at 1 min (p<0.05), and lymph flow remained above baseline for 4 min (p<0.05); all flow values after ECE were greater than corresponding values before ECE. However, the net increase in lymph flow produced by 8 min of LPT (18.3+/-3.8 mL) was not significantly greater than that observed before ECE. Moderate treadmill exercise increased lymph flow for 4 min before ECE and for 6 min after ECE. All lymph flows during exercise were greater after ECE than before ECE. The net increase in lymph flow produced by 8 min of exercise was 24.9+/-5.5 mL before ECE and 39.6+/-5.1 mL after ECE (p<0.05). CONCLUSIONS: Expansion of the extracellular fluid volume produced large increases in thoracic duct lymph flow, that were further augmented by lymphatic pump treatment and by moderate treadmill exercise.

Using the lymph fistula rat model to study the potentiation of GIP secretion by the ingestion of fat and glucose.

Glucose-dependent insulinotropic polypeptide (GIP) is an important incretin produced in the K cells of the intestine and secreted into the circulating blood following ingestion of carbohydrate- and fat-containing meals. GIP contributes to the regulation of postprandial insulin secretion and is essential for normal glucose tolerance. We have established a method of assaying GIP in response to nutrients using the intestinal lymph fistula model. Administration of Ensure, a mixed-nutrient liquid meal, stimulated a significant increase in intestinal lymphatic GIP levels that were approximately threefold those of portal plasma. Following the meal, lymph GIP peaked at 60 min (P < 0.001) and remained elevated for 4 h. Intraduodenal infusions of isocaloric and isovolumetric lipid emulsions or glucose polymer induced lymph GIP concentrations that were four and seven times the basal levels, respectively. The combination of glucose plus lipid caused an even greater increase of lymph GIP than either nutrient alone. In summary, these findings demonstrated that intestinal lymph contains high concentrations of GIP that respond to both enteral carbohydrate and fat absorption. The change in lymphatic GIP concentration is greater than the change observed in the portal blood. These studies allow the detection of GIP levels at which they exert their local physiological actions. The combination of glucose and lipid has a potentiating effect in the stimulation of GIP secretion. We conclude from these studies that the lymph fistula rat is a novel approach to study in vivo GIP secretion in response to nutrient feeding in conscious rats.

Olive oil is more potent than fish oil to reduce septic pulmonary dysfunctions in rats.

BACKGROUND: Abdominal sepsis is frequently the cause of severe pulmonary dysfunction. Via the thoracic duct, the lung is the first organ exposed to gut-derived mediators released into the mesenteric lymph. AIM: The aim of this study is to investigate whether an enteral immunonutrition with long chain triglycerides prevents septic pulmonary dysfunctions. MATERIALS AND METHODS: Mesenteric lymph was obtained from lymph fistula donor rats during sepsis (lipopolysaccharides [LPS], 5 mg/kg i.p.) with or without enteral immunonutrition (1% of olive oil or 1% of fish oil). Sepsis lymph was then reinfused into the jugular vein of separate recipient rats. Thereafter, the lung tissue was analyzed for the distance of oxygen diffusion, inflammatory response, and cell apoptosis. RESULTS: Sepsis significantly increased TNFalpha release into the mesenteric lymph, whereas an enteral immunonutrition with olive oil significantly reduced the TNFalpha release into the mesenteric lymph by more than five-fold. Sepsis lymph induced a significant increase in alveolar wall thickness, inflammatory reaction, and apoptosis; whereas sepsis lymph collected during olive oil resorption prevented the thickening of the alveolar walls and induced only a mild inflammation, being more potent than fish oil to reduce septic pulmonary dysfunction. CONCLUSIONS: Mediators in the sepsis lymph induce pulmonary dysfunction. The lung may be protected by an enteral immunonutrition containing long chain triglycerides such as olive oil.

Mechanism of the induction of brain c-Fos-positive neurons by lipid absorption.

Many gastrointestinal meal-related signals are transmitted to the central nervous system via the vagus nerve and thereby control changes in meal size. The c-Fos-positive neuron has been used as a marker of neuronal activation after lipid meals to examine the contribution of a selective macronutrient on brain neurocircuit activity. In rats fed Intralipid, the c-Fos-positive neurons were highly stimulated in the nucleus of the solitary tract (NTS) and in the hypothalamus, including the paraventricular nucleus (PVN), arcuate nucleus of the hypothalamus (ARC), and ventromedial hypothalamus at 4 h lipid feeding. However, c-Fos-like immunoreactivity was markedly attenuated in these brain regions when chylomicron formation/secretion was blocked by Pluronic L-81. After lymph was diverted from the lymph cannulated animals, the rats had a lower number of c-Fos-positive cells in the NTS and ARC. In contrast, the rats had higher c-Fos-positive neurons in PVN. The present study also revealed that c-Fos-positive neurons induced by feeding of Intalipid were abolished by CCK type 1 receptor antagonist, Lorglumide. We conclude that the formation and/or secretion of chylomicron are critical steps for initiating neuronal activation in the brain.

Octreotide and chylothorax.

PURPOSE OF REVIEW: This article reviews the current literature concerning the role of somatostatin and its synthetic analogue, octreotide, in the treatment of chylothorax. RECENT FINDINGS: Management of chylothorax includes evacuation of the pleural cavity through a chest tube to alleviate dyspnoea, and dietary fat restriction aimed at reducing lymph flow. When these measures fail to control lymph flow, surgical interventions are employed to achieve definite closure of the thoracic duct leak. Several case reports and series have shown that octreotide is safe and probably effective in both children and adults with chylothorax of different origins. The property of somatostatin and octreotide to induce leak closure is attributed to a decelerating effect on lymph flow, although their exact mechanism of action is not well defined. In successful cases, a substantial reduction of lymph drainage through the chest tube is evident within the first few days of commencing the drug, and treatment lasts for 1-2 weeks. Treatment failure has been also reported, however. SUMMARY: Accumulating evidence suggests that octreotide is a putative novel therapeutic intervention for chylothorax. It is imperative that randomized controlled studies are conducted in order to fully elucidate the efficacy and safety of this treatment.

Structure and function of the lymphatic system: an overview.

The lymphatic system is often overlooked, but is a vital part both of the circulation and the immune system. This article provides a basic overview of the structure and function of the lymphatic system as a grounding for understanding the development of chronic oedemas, notably lymphoedema.