Removal of excess fluid in acute decompensated heart failure (ADHF) targets the intravascular space, whereas most resides interstitial space. The authors evaluated an approach to decongestion using a device enhance lymph flow. was deployed sheep with induced (HF) and volume overload create low-pressure zone at thoracic duct outlet. Treatment decreased extravascular lung water (EVLW) (mL/kg) (-32% ± 9%, P = 0.029) compared controls (+46% 0.003). Device-mediated decompression effectively...

The lymphatic system returns interstitial fluid to the central venous circulation, in part, by cyclical contraction of a series "lymphangion pumps" vessel. dynamics individual lymphangions have been well characterized vitro; their frequencies and strengths are sensitive both preload afterload. However, lymphangion interaction within vessel has poorly because it is difficult experimentally alter properties afterload one coupled another. To determine effects on lymph flow, we adapted an...

The individual processes involved in interstitial fluid volume and protein regulation (microvascular filtration, lymphatic return, storage) are relatively simple, yet their interaction is exceedingly complex. There a notable lack of first-order, algebraic formula that relates pressure to critical parameters commonly used characterize the movement protein. Therefore, purpose present study develop transparent, general approach predicts ( P i ) concentrations C takes into consideration all...

In vitro studies have revealed that acute increases in transmural pressure increase lymphatic vessel contractile function. However, adaptive responses to prolonged changes vivo not been reported. Therefore, we developed a novel bovine mesenteric partial constriction model test the hypothesis vessels exposed higher pressures adapt functionally become stronger pumps than lower pressures. Postnodal were partially constricted for 3 days. On postoperative day 3, isolated, and divided into...

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To return lymph to the great veins of neck, it must be actively pumped against a pressure gradient. Mean flow in portion lymphatic network has been characterized by an empirical relationship (P(in) - P(out) = -P(p) + R(L)Q(L)), where P(in) is axial gradient and Q(L) mean flow. R(L) P(p) are parameters characterizing effective resistance pump pressure, respectively. The relation these global properties lymphangions, segments vessel bounded valves, problematic. Lymphangions have structure like...

Although the causal relationship between acute myocardial edema and cardiac dysfunction has been established, resolution of subsequent recovery function have not established. The time to resolve degree that is depressed after resolves are known. We therefore characterized temporal changes in as formed resolved.Acute was induced canine model by elevating coronary sinus pressure for three hours. Myocardial water content were determined before during elevation, restoration.Although no change...

Venomotion, spontaneous cyclic contractions of venules, was first observed in the bat wing 160 years ago. Of all functional roles proposed since then, propulsion blood by venomotion remains most controversial. Common animal models that require anesthesia and surgery have failed to provide evidence for venular pumping blood. To determine whether actively pumps a minimally invasive, unanesthetized model, we reintroduced batwing model. We evaluated temporal relationship between venous...

Under physiological conditions, interstitial fluid volume is tightly regulated by balancing microvascular filtration and lymphatic return to the central venous circulation. Even though are governed conservation of mass, their interaction can result in exceedingly complex behavior. Without making simplifying assumptions, investigators must solve balance equations numerically, which limits generality results. We thus made critical assumptions develop a simple solution standard that expressed...

Lymphangions, the segments of lymphatic vessels between two adjacent valves, actively pump lymph. Acute changes in transmural pressure and lymph flow have profound effects on function vitro. Chronic vivo also been reported to lead significant lymphangion function. Because are both cause effect adaptive processes, characterizing adaptation requires a more fundamental analysis muscle properties. Therefore, purpose present work was use an intact isovolumetric preparation evaluate mesenteric...

Lymph flow is the primary mechanism for returning interstitial fluid to blood circulation. Currently, adaptive response of lymphatic vessels mesenteric venous hypertension not known. This study sought determine functional responses postnodal vessels. We surgically occluded bovine veins create elevate lymph flow. Three days after surgery, from (MVH; n = 7) and sham surgery (Sham; 6) group animals were evaluated compared. Contraction frequency (MVH: 2.98 ± 0.75 min(-1); Sham: 5.42 0.81...

In skin, it is believed that lymph must be pumped by intrinsic contraction of lymphatic muscle, since investigators have not considered cyclical dilation venules could compress adjacent microvessels. Because vessels are sensitive to stretch, we hypothesized venomotion only can cause extrinsic pumping in nearby vessels, but also stimulate contractions. Bat wing pronounced and close proximity microvessels, studied noninvasively without the confounding effects anesthesia, surgical trauma, or...

Earlier studies leading to the common belief that lymphatic vessels are radioresistant either did not characterize pumping, deemed necessary for resolution of edema and inflammation, or it in vivo. By characterizing pumping vitro, present study, first time, demonstrated was impaired irradiated vivo enhanced vitro. Furthermore, pathways implicated ionizing radiation-induced blood vessel damage mediate responses.

Fluid and macromolecule transport from the interstitium into through lymphatic vessels is necessary for tissue homeostasis. While capillary structure suggests that passive, paracellular would be predominant route of entry, active caveolae-mediated transcellular has been identified in endothelial cells (LECs) vitro. Caveolae also mediate a wide array cell processes, including nitric oxide regulation. Thus, how does lack caveolae impact "lymphatic function"?Various aspects were measured mice...

Microvascular permeability to water is characterized by the microvascular filtration coefficient (K(f)). Conventional gravimetric techniques estimate K(f) rely on data obtained from either transient or steady-state increases in organ weight response pressure. Both result considerably different estimates and neither account for interstitial fluid storage lymphatic return. We therefore developed a theoretical framework evaluate estimation 1) comparing conventional novel technique that includes...

Abstract Objective Fluid and protein continuously transude from the surface of liver. Despite a common understanding that transudation plays critical role in hepatic interstitial peritoneal fluid balance, entire liver has not been studied. Therefore, goal present work was to provide first direct measurement rate barrier properties. Methods Transudation rates were determined by collecting transudate Hydraulic conductivity, reflection coefficients (formed subscapular matrix, capsule,...

Abstract We are leveraging Web‐based technology to create an online community for Life Science research. Our prototype cardiovascular research with live bats, called eBat, consists of local researchers as well remote collaborators. The eBat project offers scientists and students a remote‐controlled microscope conducting experiments, message board chat system scheduled spontaneous communication, peer‐reviewed manuscript repository. In this paper, we report our observations the use...

General anesthetics such as Isoflurane cause interstitial edema. Edema can result from arterial dilation (increasing transcapillary flux) or inhibition of the lymphatic pumps (decreasing removal volume). The mechanism edema formation has not been determined because microvascular studies in common animal models require anesthesia—preventing a baseline for comparison. Our model, Pallid batwing, allows noninvasive intravital microscopy without anesthesia. We therefore used batwing model to test...

The role of the hepatic transudation barrier in determining ascites volume and protein content chronic liver disease is poorly understood. Therefore, purpose present study was to characterize how sinusoidal hypertension impacts properties rate. suprahepatic inferior vena cava surgically constricted, animals were exposed either short-term (SVH; 2–3 wk) or long-term venous (LVH; 5–6 wk). Compared with SVH, LVH resulted lower peritoneal fluid pressure, volume, concentration. reflection...

Modest increases in pulmonary interstitial fluid pressure ( P i ) can lead to alveolar flooding and respiratory failure. Arising from the complex interaction of microvascular filtration, lymphatic drainage, as well cardiac, renal venous function, is typically predicted by mathematical models that are notoriously complex, difficult interpret, solvable only those with advanced programming skills. Therefore, we developed a simple model predicts function critical cardiovascular parameters....

The tolerance to hemorrhage, effectiveness of fluid resuscitation, and the transport inflammatory mediators, all depend on how redistributes between vascular interstitial compartments. Fluid redistribution depends complex interaction cardiac function, venous capacitance, arterial resistances, microvascular filtration lymphatic function. promise mathematical models elucidate physiology shock has suffered from very complexity they aim address, leading numerical solutions that only apply for a...

Edemagenic challenges can make passive lymph flow so high that active lymphatic vessel pumping may not be necessary to propel lymph. Indeed, an acute increase in is reported decrease contraction frequency and strength vitro. However, the response a chronic vivo unknown. We hypothesized vessels become weaker pumps when exposed sustained flow. surgically occluded bovine mesenteric veins create venous hypertension conditions. Three days after surgery, post‐nodal (MVH) were isolated compared...

The anatomical interconnections between the liver and intestines make interstitial fluid balance complex experimental data exceedingly difficult to interpret. portal vein connects intestinal hepatic blood circulations, cisterna chyli lymphatic systems. Furthermore, mathematical models designed relate volumes lymph flows critical parameters either oversimplify system or overcomplicate vascular system. Therefore, we developed a model that predicts pressures by adjusting relative complexity of...

Short-chain fatty acids (SCFAs; acetate (AC), propionate (PP), and butyrate (BT)) are the primary metabolites of intestinal microbiota. In addition to being an epithelial energy source, SCFAs exert numerous local effects, including maintenance barrier integrity protection against inflammation, commonly assumed beneficial. It is also well understood that mesenteric lymphatic function vital for normal gut health; impaired pumping leads interstitial accumulation fluid immune cells, inducing...