Intrinsic contractility of prenodal lymph vessels and lymph flow in human leg

Wl, Olszewski; Engeset, A

doi:10.1152/ajpheart.1980.239.6.h775

Cited by 138 publications

(153 citation statements)

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“…These methods were mostly performed in large animals, such as dog, cow, sheep, and, in some cases, have even been carried out in humans (20,(27)(28)(29). However, for many organs the lymphatic outflow pathways are complicated and, therefore, many vessels would require cannulation to accurately measure lymphatic transport.…”

Section: Discussionmentioning

confidence: 99%

Quantitative measurement of lymphatic function in mice by noninvasive near-infrared imaging of a peripheral vein

Proulx¹,

Ma²,

Andina³

et al. 2017

JCI Insight

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Section: Discussionmentioning

confidence: 99%

Quantitative measurement of lymphatic function in mice by noninvasive near-infrared imaging of a peripheral vein

Proulx¹,

Ma²,

Andina³

et al. 2017

JCI Insight

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“…Inflating a cuff on the upper portion of a healthy individual's arm will decrease the lymphatic drainage from that limb with total cessation when cuff pressures reach the range of 40 -70 mmHg (13,23). In the leg, cuff obstruction inhibits flow at 55-70 mmHg (13): cannulated healthy collecting lymphatics demonstrate resting pressures of 30 -50 mmHg (37) and 55 mmHg and higher when deliberately obstructed (25). Acute compression of the thoracic duct during surgical conditions has been reported to result in developed pressures of 30 -50 mmHg (15).…”

Section: Discussionmentioning

confidence: 99%

Human thoracic duct in vitro: diameter-tension properties, spontaneous and evoked contractile activity

Telinius

Drewsen

Pilegaard

et al. 2010

American Journal of Physiology-Heart and Circulatory Physiology

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The current study characterizes the mechanical properties of the human thoracic duct and demonstrates a role for adrenoceptors, thromboxane, and endothelin receptors in human lymph vessel function. With ethical permission and informed consent, portions of the thoracic duct (2-5 cm) were resected and retrieved at T7-T9 during esophageal and cardia cancer surgery. Ring segments (2 mm long) were mounted in a myograph for isometric tension (N/m) measurement. The diameter-tension relationship was established using ducts from 10 individuals. Peak active tension of 6.24 Ϯ 0.75 N/m was observed with a corresponding passive tension of 3.11 Ϯ 0.67 N/m and average internal diameter of 2.21 mm. The equivalent active and passive transmural pressures by LaPlace's law were 47.3 Ϯ 4.7 and 20.6 Ϯ 3.2 mmHg, respectively. Subsequently, pharmacology was performed on rings from 15 ducts that were normalized by stretching them until an equivalent pressure of 21 mmHg was calculable from the wall tension. At low concentrations, norepinephrine, endothelin-1, and the thromboxane-A2 analog U-46619 evoked phasic contractions (analogous to lymphatic pumping), whereas at higher contractions they induced tonic activity (maximum tension values of 4.46 Ϯ 0.63, 5.90 Ϯ 1.4, and 6.78 Ϯ 1.4 N/m, respectively). Spontaneous activity was observed in 44% of ducts while 51% of all the segments produced phasic contractions after agonist application. Acetylcholine and bradykinin relaxed norepinephrine preconstrictions by ϳ20% and ϳ40%, respectively. These results demonstrate that the human thoracic duct can develop wall tensions that permit contractility to be maintained across a wide range of transmural pressures and that isolated ducts contract in response to important vasoactive agents. lymphatic system; lymph pump; lymphangion; lymphatic smooth muscle THE EXCESS FLUID AND PROTEIN of the interstitial spaces in almost all tissues of the body are collected and removed by the lymphatic system. The lymphatic capillaries converge into larger collecting lymphatics, and, ultimately, these terminate into large transport vessels, which return lymph to the blood circulation. The lymphatic system lacks a central pump to drive the transport of lymph. Instead, it is generally accepted that the lymphatic smooth muscle cells (LSMCs) in the collecting and transporting lymphatic vessel wall are responsible for propelling lymph forward by intrinsic contractions. The lymphatic vessels responsible for pumping are comprised of multiple contractile segments separated by unidirectional valves to prevent backflow, termed a lymphangion, and each lymphangion performs much like a cardiac ventricle to provide unidirectional pumping. The contractile part of the lymphatic vasculature can thus be likened to a system of ventricles in series (27). The thoracic duct is the largest lymphatic vessel in the human body. Under normal conditions (i.e., in healthy individuals), it is a low-flow system that drains up to 1 ml/min to the venous circulation (30,44). The volume and flow of lymph a...

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“…Nevertheless, they produce co-ordinated spontaneous activity which results in efficient propulsion of fluid (Hall, Morris & Woolley, 1965;McHale & Roddie, 1976;Olszewski & Engeset, 1980). Our approach in the past has been to study the lymph vessels of large ruminants, which are well developed and more robust than the vessels of smaller species, making them suitable for mechanical studies of pumping activity (McHale & Roddie, 1976;McHale & Thornbury, 1986;McGeown, McHale & Thornbury, 1987).…”

Section: Discussionmentioning

confidence: 99%

Outward Currents in Smooth Muscle Cells Isolated from Sheep Mesenteric Lymphatics

Cotton

Hollywood

McHale

et al. 1997

The Journal of Physiology

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The patch‐clamp technique was used to measure membrane currents in isolated smooth muscle cells dispersed from sheep mesenteric lymphatics. Depolarizing steps positive to −30 mV evoked rapid inward currents followed by noisy outward currents. Nifedipine (1 μM) markedly reduced the outward current, while Bay K 8644 (1 μM) enhanced it. Up to 90% of the outward current was also blocked by iberiotoxin (Kd= 36 nM). Large conductance (304 ±15 pS, 7 cells), Ca2+‐ and voltage‐sensitive channels were observed during single‐channel recordings on inside‐out patches using symmetrical 140 mM K+ solutions (at 37 °C). The voltage required for half‐maximal activation of the channels (V½) shifted in the hyperpolarizing direction by 146 mV per 10‐fold increase in [Ca2+]i. In whole‐cell experiments a voltage‐dependent outward current remained when the Ca2+‐activated current was blocked with penitrem A (100 nM). This current activated at potentials positive to −20 mV and demonstrated the phenomenon of voltage‐dependent inactivation (V½=−41 ± 2 mV, slope factor = 18 ± 2 mV, 5 cells). Tetraethylammonium (TEA; 30 mM) reduced the voltage‐dependent current by 75% (Kd= 3.3 mM, 5 cells) while a maximal concentration of 4‐aminopyridine (4‐AP; 10 mM) blocked only 40% of the current. TEA alone had as much effect as TEA and 4‐AP together, suggesting that there are at least two components to the voltage‐sensitive K+ current. These results suggest that lymphatic smooth muscle cells generate a Ca2+‐activated current, largely mediated by large conductance Ca2+‐activated K+ channels, and several components of voltage‐dependent outward current which resemble ‘delayed rectifier’ currents in other smooth muscle preparations.

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Intrinsic contractility of prenodal lymph vessels and lymph flow in human leg

Cited by 138 publications

References 0 publications

Quantitative measurement of lymphatic function in mice by noninvasive near-infrared imaging of a peripheral vein

Quantitative measurement of lymphatic function in mice by noninvasive near-infrared imaging of a peripheral vein

Human thoracic duct in vitro: diameter-tension properties, spontaneous and evoked contractile activity

Outward Currents in Smooth Muscle Cells Isolated from Sheep Mesenteric Lymphatics

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