Lymph

Lymph

Lymph is the fluid that is formed as the interstitial fluid enters the lymph vessels by filtration. The lymph then travels to at least one lymph node before emptying ultimately into the right or the left subclavian vein, where it mixes back with blood.

Composition of lymph

Lymph has a composition comparable to that of plasma, but it is different in various parts of the body depending upon the tissue drained. In particular, the lymph that leaves a lymph node is richer in lymphocytes. Likewise, the lymph formed in the digestive system called chyle is rich in triglycerides (fat), and looks white.

Formation of lymph

Blood supplies nutrients, and important metabolites to the tissues, and collects back the waste products that they produce, which requires exchange of respective constituents between the blood and tissues. However, this exchange is not direct, and is effected through an intermediary called "interstitial fluid" or "tissue fluid" that the blood forms. Interstitial fluid (ISF) is the fluid that occupies the spaces between the cells and acts as their immediate environment. As the blood and the surrounding cells continually add and remove substances from the ISF, its composition keeps on changing. Water and solutes can freely pass (diffuse) between the ISF and blood, and thus both are in dynamic equilibrium with each other; exchange between the two fluids occurs across the walls of small blood vessels called capillaries.

ISF forms at the arterial (coming from the heart) end of the capillaries because of higher pressure of blood, and "most of it" returns to its venous ends and venules; the rest (10—20%) enters the lymph capillaries as lymph.]

Unlike the cardiovascular system, the lymphatic system is not closed and has no central pump. Lymph movement occurs despite low pressure due to peristalsis (propulsion of the lymph due to alternate contraction and relaxation of smooth muscle), valves, and compression during contraction of adjacent skeletal muscle and arterial pulsation.cite journal | author = Shayan, Ramin; Achen, Marc G.; Stacker, Steven A.
year = 2006 | title = Lymphatic vessels in cancer metastasis: bridging the gaps | volume = 27 | issue = 9 | pages = 1729 | doi = 10.1093/carcin/bgl031 | url = http://carcin.oxfordjournals.org/cgi/content/full/27/9/1729 | pmid = 16597644 | journal = Carcinogenesis
]

Usually, the lymph that enters the lymph vessels from the interstitial space, does not leak back because of presence of valves. But, in case of blockage of free flow, when excessive hydrostatic pressure develops within the lymph vessels, some fluid can leak back and contribute to formation of edema.

See also

* Lymphatic system
* Lymphedema

References


Wikimedia Foundation. 2010.

Игры ⚽ Нужен реферат?

Look at other dictionaries:

  • lymph — lymph·ad·e·ni·tis; lymph·ad·e·no·ma; lymph·ad·e·nop·a·thy; lymph·ad·e·no·sis; lymph·an·gi·o·ma; lymph·ede·ma; lymph·oid; lymph·ous; peri·lymph; …   English syllables

  • Lymph — Lymph, n. [L. lympha: cf. F. lymphe.] 1. A spring of water; hence, water, or a pure, transparent liquid like water. [1913 Webster] A fountain bubbled up, whose lymph serene Nothing of earthly mixture might distain. Trench. [1913 Webster] 2. (Anat …   The Collaborative International Dictionary of English

  • lymph- — lymph(o) ♦ Élément, du lat. lympha ou de lymphe. ⇒LYMPH(O) , (LYMPH , LYMPHO )élém. de compos. Élém. représentant le subst. lymphe dans la constr. de termes de méd. et de biol. A. [Les mots constr. sont des subst.] 1. [Le 2e élém. existe aussi… …   Encyclopédie Universelle

  • lymph|e|de|ma — «LIHM fih DEE muh», noun. edema caused by the abnormal accumulation of lymph fluid: »In lymphedema there is insufficient drainage of fluid, and proteins (Scientific American). ╂[< New Latin lympha lymph + edema] …   Useful english dictionary

  • lymph... — lymph..., Lymph... vgl. ↑lympho..., Lympho …   Das große Fremdwörterbuch

  • lymph — 1725 in physiology sense, colorless fluid found in the body, from Fr. lymphe, from L. lympha water, clear water, a goddess of water, variant of lumpæ waters, altered by influence of Gk. nymphe goddess of a spring, nymph. The word was used earlier …   Etymology dictionary

  • lymph — lymph. См. лимфа. (Источник: «Англо русский толковый словарь генетических терминов». Арефьев В.А., Лисовенко Л.А., Москва: Изд во ВНИРО, 1995 г.) …   Молекулярная биология и генетика. Толковый словарь.

  • lymph — [lımf] n [U] [Date: 1600 1700; : Latin; Origin: lympha water goddess, water , from Greek nymphe; NYMPH] a clear liquid that is formed in your body and passes into your blood system to fight against infection >lymphatic [lımˈfætık] adj …   Dictionary of contemporary English

  • lymph — [ lımf ] noun uncount a clear liquid in your body that destroys harmful bacteria …   Usage of the words and phrases in modern English

  • lymph — ► NOUN 1) a colourless fluid containing white blood cells, which bathes the tissues and drains through the lymphatic system into the bloodstream. 2) fluid exuding from a sore or inflamed tissue. ORIGIN Latin lympha, limpa water …   English terms dictionary

Share the article and excerpts

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