HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via Google Scholar Google Scholar Articles by Kaiser, K. P. Articles by Feinendegen, L. E. Search for Related Content PubMed PubMed Citation Articles by Kaiser, K. P. Articles by Feinendegen, L. E.

Tracer Kinetics of 15-(Ortho-^123/131I-Phenyl)-Pentadecanoic Acid (oPPA) and 15-(Para-^123/131I-Phenyl)-Pentadecanoic Acid (pPPA) in Animals and Man

Institute of Medicine, Nuclear Research Center, Jülich, FRG
Department of Cardiology, University of Düsseldorf, Düsseldorf, FRG
Univeristy of Connecticut and VA Medical Center, Newington, Connecticut
Institute of Medical Radiation Physics, University of Essen, FRG

Correspondence: For reprints contact: Prof. Dr. Ludwig E. Feinendegen, Institute of Medicine, Nuclear Research Center, P.O. Box 1913, D-5170 Jülich, West Germany.

ABSTRACT

The human myocardium retains oPPA as opposed to pPPA. Therefore turnover of oPPA was compared with that of pPPA in rat hearts and in man, the latter by using substrates double-labeled with ^123/131I and ¹⁴C. Moreover, substrate binding to coenzyme-A was tested in vitro. In rats, oPPA remained mainly in the pool of free fatty acids, as opposed to pPPA, which was metabolized by mitochondrial ß-oxidation. Binding to coenzyme-A at maximum was 62% for oPPA, 81% for pPPA and 90% for palmitic acid.

In man, after i.v. and intracoronary injection of double-labeled oPPA, the two radionuclides reappeared together in venous blood and in coronary sinus respectively, in an unchanged ratio but at a significantly lower rate than with pPPA. It can be concluded that oPPA is bound to coenzyme-A and is retained in the cytosolic lipid pool, while pPPA is metabolized by mitochondrial ß-oxidation. A dual-tracer application of oPPA and pPPA has the potential of being a specific probe for the function of the carnitine shuttle.