Clinical Chemistry Link to Randox Laboratories Web Site
HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
QUICK SEARCH:   [advanced]


     

Clinical Chemistry 42: 270-278, 1996;
This Article
Right arrow Full Text (PDF)
Right arrow Submit an electronic Letter to
the Editor about this paper
Right arrow Alert me when this article is cited
Right arrow Alert me when eLetters are posted
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
Right arrow reprints & permissions
Citing Articles
Right arrow Citing Articles via HighWire
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Paci, A.
Right arrow Articles by Biver, P.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Paci, A.
Right arrow Articles by Biver, P.

Clinical Chemistry, Vol 42, 270-278, Copyright © 1996 by American Association for Clinical Chemistry

Human placenta radioreceptor assay with digoxin and ouabain to detect endogenous digitalis-like factor(s) in human plasma and urine

A Paci, G Ciarimboli and P Biver
Istituto di Fisiologia Clinica del CNR, Pisa, Italy.

We describe the optimization and validation of a clinically feasible radioreceptor assay to detect endogenous digitalis-like factor(s) (EDLF) in human plasma and urine. The assay is based on the competitive replacement of 125I-labeled digoxin on human placenta membranes by ligands present in sample extracts. Digoxin and ouabain were used as calibrators. We also describe simple and effective methods for extraction and enrichment of EDLF from human plasma and urine. Assay sensitivity and precision were enhanced by using a sequential saturation technique with appropriate concentrations of tracer and receptors. Filtration was used to separate bound from free ligand. A two-step solid-state extraction with acetonitrile allowed the separation of two EDLFs with different polarity (EDLF-1 and EDLF-2) from the same plasma sample. A one-step solid-state extraction with methanol was suitable for urine. EDLF-1 and EDLF-2 in healthy adults were respectively 204 +/- 155 and 207 +/- 423 pmol/L ouabain equivalents, or 312 +/- 241 and 302 +/- 581 pmol/L digoxin equivalents. Plasma concentrations of EDLFs in newborns and pregnant women were higher than in healthy adults, and the concentrations in urine were higher than in plasma. Several cross-reactivity experiments showed that physiological concentrations of endogenous steroids and lipids did not inhibit binding, and supported the hypothesis that EDLFs are endogenous compounds other than the steroids and lipids also investigated.


The following articles in journals at HighWire Press have cited this article:


Home page
 Clin. Chem.Home page
H. M.A.M. Qazzaz, Z. Cao, D. D. Bolanowski, B. J. Clark, and R. Valdes Jr
De Novo Biosynthesis and Radiolabeling of Mammalian Digitalis-Like Factors
Clin. Chem., March 1, 2004; 50(3): 612 - 620.
[Abstract] [Full Text] [PDF]

Home page
 Exp. Biol. Med.Home page
R. I. Dmitrieva and P. A. Doris
Cardiotonic Steroids: Potential Endogenous Sodium Pump Ligands with Diverse Function
Experimental Biology and Medicine, September 1, 2002; 227(8): 561 - 569.
[Abstract] [Full Text] [PDF]

Home page
 EndocrinologyHome page
H. M. A. M. Qazzaz, M. A. El-Masri, and R. Valdes Jr.
Secretion of a Lactone-Hydrogenated Ouabain-Like Effector of Sodium, Potassium-Adenosine Triphosphatase Activity by Adrenal Cells
Endocrinology, September 1, 2000; 141(9): 3200 - 3209.
[Abstract] [Full Text] [PDF]


HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
Copyright © 1996 by the American Association for Clinical Chemistry.