World Library  
Flag as Inappropriate
Email this Article

Ascending limb of loop of Henle

Article Id: WHEBN0008115555
Reproduction Date:

Title: Ascending limb of loop of Henle  
Author: World Heritage Encyclopedia
Language: English
Subject: External sphincter muscle of female urethra, Ureteropelvic junction, Medullary ray (anatomy), Orifice of ureter, Neck of urinary bladder
Collection: Kidney Anatomy
Publisher: World Heritage Encyclopedia

Ascending limb of loop of Henle

Ascending limb of loop of henil
Scheme of renal tubule and its vascular supply. (Labeled at center left.)
Nephron ion flow diagram
Latin tubulus rectus distalis, pars recta tubuli distalis
Anatomical terminology

The ascending limb of loop of Henle is a segment of the nephron in the kidney divided into a thin and thick ascending limb (also known as distal straight tubule).


  • Structure 1
    • Histology 1.1
  • Function 2
    • Thin ascending limb 2.1
    • Thick ascending limb 2.2


The ascending limb of the loop of Henle is a direct continuation from the descending limb of loop of Henle, and one of the structures in the nephron of the kidney. The ascending limb has a thin and a thick segment. The ascending limb drains urine into the distal convoluted tubule.

The thin ascending limb is found in the medulla of the kidney, and the thick ascending limb can be divided into a part that is in the renal medulla and a part that is in the renal cortex. The ascending limb is much thicker than the descending limb.


As in the descending limb, the epithelium is simple squamous epithelium.


Thin ascending limb

The thin ascending limb is impermeable to water and ions, except sodium and chloride which cross by diffusion.

Thick ascending limb

Functionally, the parts of the ascending limb in the medulla and cortex are very similar.

The medullary ascending limb remains impermeable to water. Sodium (Na+), potassium (K+) and chloride (Cl) ions are reabsorbed by active transport. K+ is passively transported along its concentration gradient through a K+ leak channel in the apical aspect of the cells, back into the lumen of the ascending limb. This K+ "leak" generates a positive electrochemical potential difference in the lumen. This drives more paracellular reabsorption of Na+, as well as other cations such as magnesium (Mg2+) and importantly calcium Ca2+ due to charge repulsion.

This is also the part of the tubule that generates Tamm-Horsfall protein. The function of this protein is not well understood, but is responsible for creating

This article was sourced from Creative Commons Attribution-ShareAlike License; additional terms may apply. World Heritage Encyclopedia content is assembled from numerous content providers, Open Access Publishing, and in compliance with The Fair Access to Science and Technology Research Act (FASTR), Wikimedia Foundation, Inc., Public Library of Science, The Encyclopedia of Life, Open Book Publishers (OBP), PubMed, U.S. National Library of Medicine, National Center for Biotechnology Information, U.S. National Library of Medicine, National Institutes of Health (NIH), U.S. Department of Health & Human Services, and, which sources content from all federal, state, local, tribal, and territorial government publication portals (.gov, .mil, .edu). Funding for and content contributors is made possible from the U.S. Congress, E-Government Act of 2002.
Crowd sourced content that is contributed to World Heritage Encyclopedia is peer reviewed and edited by our editorial staff to ensure quality scholarly research articles.
By using this site, you agree to the Terms of Use and Privacy Policy. World Heritage Encyclopedia™ is a registered trademark of the World Public Library Association, a non-profit organization.

Copyright © World Library Foundation. All rights reserved. eBooks from Project Gutenberg are sponsored by the World Library Foundation,
a 501c(4) Member's Support Non-Profit Organization, and is NOT affiliated with any governmental agency or department.