Lymphangion

Lymphangion

A lymphangion is the functional unit of a lymph capillary or lymph vessel that lies between two semilunar (half moon-shaped) valves.Citation
first = A.M.
last = Venugopal
author-link =
first2 = R.H.
last2 = Stewart
first3 = G.A.
last3 = Laine
first4 = C.M.
last4 = Quick
contribution = Optimal Lymphatic Vessel Structure
contribution-url = http://ieeexplore.ieee.org/search/wrapper.jsp?arnumber=1404039
title = 26th Annual International Conference of the IEEE
volume = 2
year = 2004
pages = 3700—3703
place =
publisher = Engineering in Medicine and Biology Society
url = http://ieee.org/portal/site
doi =
id =
]

Lymph vessels are channels larger than the lymph capillaries that have thicker walls and smooth muscles in their walls, thus lymph vessel lymphangion would be muscular, and capable of contracting on its own. The capillary lymphangion on the other hand does not have smooth muscles, and the lymph in it is propelled forward only because of force exerted on its walls from the exterior. Such forces include skeletal muscle contractions and arterial pulsations. Also, the inspiration during respiration provides a suction pressure within the lumen.

The semilunar valves are directed towards the flow of the lymph and open when the pressure in the first lymphangion is greater than the pressure in the next lymphangion. Pressure in the first lymphangion may increase because of smooth muscle contraction (in lymph vessel) or because of pressure on the walls from outside (in a capillary) result because of. Alternatively, pressure within the next lymphangion may decrease because of negative pressure as a result of inspiration. Once, the lymph flows into the next lymphangion, it cannot return to the previous lymphangion, as the semilunar valves close tightly.

In conditions when the pressure in a lymphatic is sufficiently great, the valves may fail, and there can indeed be backward flow of lymph resulting in edema of the drained region. This may happen with blockade of lymph flow because of pathology in the draining lymph node or at some point in the vessel.

References


Wikimedia Foundation. 2010.

Игры ⚽ Поможем написать реферат

Look at other dictionaries:

  • Lymphangion — Pour les articles homonymes, voir vaisseau. « Train » de lymphangions. La flèche jaune donne le sens de circulation de la la lymphe. Comme celles des capillaires sangins, Les parois des lymphangions ne sont p …   Wikipédia en Français

  • Lymphangion — Als Lymphangion wird jener Teil eines Lymphgefäßes bezeichnet, der zwischen zwei Klappen liegt. Diese sind, ähnlich wie bei den Venen, als Duplikatur der Endothelzellschicht zu betrachten. Das Lymphangion besitzt eine längsverlaufende und eine… …   Deutsch Wikipedia

  • lymphangion — A lymphatic vessel. See lymph vessels, under vessel. [L. lympha, lymph, + G. angeion, vessel] * * * lym·phan·gi·on (lim fanґje on) vas lymphaticum …   Medical dictionary

  • Système lymphatique — Pour les articles homonymes, voir Réseau. Représentation très simplifiée du système lymphatique humain …   Wikipédia en Français

  • lymphangi- — combining form or lymphangio Etymology: New Latin, from lymphangion lymphatic vessel, from lymph + Greek angeion vessel, blood vessel more at angi : lymphatic vessels lymphangiectasis …   Useful english dictionary

  • Blood — For other uses, see Blood (disambiguation). Human blood smear: a – erythrocytes; b – neutrophil; c – eosinophil; d – lymphocyte …   Wikipedia

  • Circulatory system — This article is about the organ system. For the band, see Circulatory System. For transport in plants, see Vascular tissue. Circulatory system …   Wikipedia

  • Lymphatic system — Infobox Anatomy Name = Lymphatic System Caption = An image displaying the lymphatic system.The lymphatic system in vertebrates is a network of conduits that carry a clear fluid called lymph. It also includes the lymphoid tissue through which the… …   Wikipedia

  • Thoracic duct — Lymph: Thoracic duct The thoracic and right lymphatic ducts. (Thoracic duct is thin vertical white line at center.) …   Wikipedia

  • Cisterna chyli — Lymph: Cisterna chyli; Cysterna Chyli …   Wikipedia

Share the article and excerpts

Direct link
Do a right-click on the link above
and select “Copy Link”