Jump to content
 







Main menu
   


Navigation  



Main page
Contents
Current events
Random article
About Wikipedia
Contact us
Donate
 




Contribute  



Help
Learn to edit
Community portal
Recent changes
Upload file
 








Search  



























Create account

Log in
 









Create account
 Log in
 




Pages for logged out editors learn more  



Contributions
Talk
 



















Contents

   



(Top)
 


1 References  





2 External links  














Lacteal






العربية

فارسی
Français

Italiano


 

Edit links
 









Article
Talk
 

















Read
Edit
View history
 








Tools
   


Actions  



Read
Edit
View history
 




General  



What links here
Related changes
Upload file
Special pages
Permanent link
Page information
Cite this page
Get shortened URL
Download QR code
Wikidata item
 




Print/export  



Download as PDF
Printable version
 


















From Wikipedia, the free encyclopedia
 


Lacteal
Transverse section of a villus, from the human intestine. X 350.
a. Basement membrane, here somewhat shrunken away from the epithelium.
b. Lacteal.
c. Columnar epithelium.
d. Its striated border.
e. Goblet cells.
f. Leucocytes in epithelium.
f’. Leucocytes below epithelium.
g. Bloodvessels.
h. Muscle cells cut across.
Villi of small intestine, showing bloodvessels and lymphatic vessels.
Anatomical terminology

[edit on Wikidata]

Alacteal is a lymphatic capillary that absorbs dietary fats in the villi of the small intestine.

Triglycerides are emulsified by bile and hydrolyzed by the enzyme lipase, resulting in a mixture of fatty acids, di- and monoglycerides.[1] These then pass from the intestinal lumen into the enterocyte, where they are re-esterified to form triglyceride. The triglyceride is then combined with phospholipids, cholesterol ester, and apolipoprotein B48 to form chylomicrons. These chylomicrons then pass into the lacteals, forming a milky substance known as chyle. The lacteals merge to form larger lymphatic vessels that transport the chyle to the thoracic duct where it is emptied into the bloodstream at the subclavian vein.[2][3]

At this point, the fats are in the bloodstream in the form of chylomicrons. Once in the blood, chylomicrons are subject to delipidation by lipoprotein lipase. Eventually, enough lipid has been lost and additional apolipoproteins gained, that the resulting particle (now referred to as a chylomicron remnant) can be taken up by the liver. From the liver, the fat released from chylomicron remnants can be re-exported to the blood as the triglyceride component of very low-density lipoproteins. Very low-density lipoproteins are also subject to delipidation by vascular lipoprotein lipase, and deliver fats to tissues throughout the body. In particular, the released fatty acids can be stored in adipose cells as triglycerides. As triglycerides are lost from very low-density lipoproteins, the lipoprotein particles become smaller and denser (since protein is denser than lipid) and ultimately become low-density lipoproteins. LDL particles are highly atherogenic.[4]

In contrast to any other route of absorption from the small intestine, the lymphatic system avoids first pass metabolism.

References[edit]

  1. ^ Young, Barbara; Wheater, Paul, eds. (2006). Wheater's functional histology: a text and colour atlas. Elsevier Health Sciences. p. 279. ISBN 978-0-443-06850-8.
  • ^ Newsholme, Eric; Leech, Anthony (2009). Functional Biochemistry in Health and Disease. John Wiley & Sons. p. 79. ISBN 978-0-471-98820-5.
  • ^ Montague, Susan E.; et al., eds. (2005). Physiology for nursing practice. Elsevier. p. 502. ISBN 978-0-7020-2676-8.
  • ^ Carmena, Rafael; Duriez, Patrick; Fruchart, Jean-Charles (2004-06-15). "Atherogenic Lipoprotein Particles in Atherosclerosis". Circulation. 109 (23_suppl_1): III–2. doi:10.1161/01.CIR.0000131511.50734.44. PMID 15198959. S2CID 15994547.
  • External links[edit]

  • icon Medicine

  • Retrieved from "https://en.wikipedia.org/w/index.php?title=Lacteal&oldid=1197268716"

    Categories: 
    Digestive system
    Lymphatic system
    Lymphatic tissue
    Hidden categories: 
    Articles with short description
    Short description matches Wikidata
    Articles using infobox templates with no data rows
     



    This page was last edited on 19 January 2024, at 20:31 (UTC).

    Text is available under the Creative Commons Attribution-ShareAlike License 4.0; additional terms may apply. By using this site, you agree to the Terms of Use and Privacy Policy. Wikipedia® is a registered trademark of the Wikimedia Foundation, Inc., a non-profit organization.



    Privacy policy

    About Wikipedia

    Disclaimers

    Contact Wikipedia

    Code of Conduct

    Developers

    Statistics

    Cookie statement

    Mobile view



    Wikimedia Foundation
    Powered by MediaWiki