AJP - Renal Fuel your research with LabChart
HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
QUICK SEARCH:   [advanced]


     

Am J Physiol Renal Physiol 270: F604-F613, 1996;
0363-6127/96 $5.00
This Article
Right arrow Full Text (PDF)
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Services
Right arrow Email this article to a friend
Right arrow Similar articles in this journal
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Citing Articles
Right arrow Citing Articles via HighWire
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Asplin, J. R.
Right arrow Articles by Coe, F. L.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Asplin, J. R.
Right arrow Articles by Coe, F. L.

AJP - Renal Physiology, Vol 270, Issue 4 604-F613, Copyright © 1996 by American Physiological Society

ARTICLES

Evidence of calcium phosphate supersaturation in the loop of Henle

J. R. Asplin, N. S. Mandel and F. L. Coe
Nephrology Section, University of Chicago, Illinois 60637, USA.

We have used published rat micropuncture data to construct a matrix of ion concentrations along the rat nephron. With an iterative computer model of known ion interactions, we calculated relative supersaturation ratios in all nephron segments. The collecting ducts and urine showed expected supersaturation with stone-forming salts. Fluid in the thin segment of the loop of Henle may be supersaturated with calcium carbonate and calcium phosphate under certain conditions. Because calculations cannot predict the actual course of crystallization, we made solutions to mimic, in vitro, presumed conditions in the loop of Henle. The solid phases that formed were analyzed by X-ray powder diffraction, electron microprobe, and infrared spectroscopy. All samples were identified as poorly crystallized or immature apatite. The descending limb of Henle's loop creates a unique condition as it extracts water but not sodium, bicarbonate, calcium, or phosphate, giving a calcium concentration at the bend of 3 mM, pH 7.4, and a phosphate concentration that varies from 0.8 to 48 mM, depending on parathyroid hormone and dietary phosphate. We conclude that conditions in the thin segment potentially could create a solid calcium phosphate phase, which may initiate nucleation of calcium oxalate salts in the collecting ducts, potentiating nephrolithiasis and nephrocalcinosis.


This article has been cited by other articles:


Home page
 Am. J. Physiol. Renal Physiol.Home page
S. N. Pillay, J. R. Asplin, and F. L. Coe
Evidence that calgranulin is produced by kidney cells and is an inhibitor of calcium oxalate crystallization
Am J Physiol Renal Physiol, August 1, 1998; 275(2): F255 - F261.
[Abstract] [Full Text] [PDF]

Home page
 J. Biol. Chem.Home page
S. Waldegger and T. J. Jentsch
Functional and Structural Analysis of ClC-K Chloride Channels Involved in Renal Disease
J. Biol. Chem., August 4, 2000; 275(32): 24527 - 24533.
[Abstract] [Full Text] [PDF]


HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
Visit Other APS Journals Online