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 HighWire Citing Articles via Google Scholar Google Scholar Articles by Bøtker, H. E. Articles by Taegtmeyer, H. Search for Related Content PubMed PubMed Citation Articles by Bøtker, H. E. Articles by Taegtmeyer, H.

Myocardial Glucose Uptake Measured with Fluorodeoxyglucose: A Proposed Method to Account for Variable Lumped Constants

Department of Internal Medicine, Division of Cardiology, University of Texas, Houston Medical School, Houston, Texas
Department of Medical Physics, University of Wisconsin, Medical Sciences Center, Madison, Wisconsin
Department of Cardiology, Skejby Hospital, Aarhus University Hospitals, Aarhus N
PET Center, Aarhus General Hospital, Aarhus University Hospitals, Aarhus C, Denmark

Correspondence: For correspondence or reprints contact: Heinrich Taegtmeyer, MD, DPhil, Department of Internal Medicine, Division of Cardiology, University of Texas, Houston Medical School, 6431 Fannin, MSB 1246, Houston, TX 77030.

ABSTRACT

Quantitative assessment of myocardial glucose uptake by the glucose tracer analog 2-deoxy-2-[¹⁸F]fluoro-D-glucose (FDG) depends on a correction factor (lumped constant [LC]), which may vary. We propose that this variability is caused by different affinities of FDG and glucose for membrane transport and phosphorylation and can be predicted from the time course of FDG retention. We therefore measured the LC under steadystate metabolic conditions and compared the results with values predicted from the tracer retention alone. Methods: We measured rates of myocardial glucose uptake by tracer ([2-³H]glucose) and tracer analog methods (FDG) in isolated working Sprague-Dawley rat hearts perfused with Krebs buffer and glucose, or glucose plus insulin or ß-hydroxybutyrate. In separate experiments, we established the theoretical upper and lower limits for the LC (R_t and R_p), which are determined by the relative rates of FDG and glucose membrane transport (R_t, 1.73 ± 0.22) and the relative rales of FDG and glucose phosphorylation (R_p, 0.15 ± 0.04). Results: The LC was decreased in the presence of insulin or ß-hydroxybutyrateor both (from 1.14 ± 0.3 to 0.58 ± 0.16 [insulin], to 0.75 ± 0.17 [ß-hydroxybutyrate] or to 0.53 ± 0.17 [both], P < 0.05). The time-activity curves of FDG retention reflected these changes. Combining the upper and lower limits for the LC with the ratio between unidirectional and steady-state FDG uptake rates allowed the prediction of individual LCs, which agreed well with the actually measured values (r = 0.96, P < 0.001 ). Conclusion: The LC is not a constant but is a predictable quotient. As a result of the fixed relation between tracer and tracee for both membrane transport and phosphorylation, the quotient can be determined from the FDG time-activity curve and true rates of myocardial glucose uptake can be measured.

Key Words: PET • enzyme kinetics • hormones • membrane transport • hexokinase

This article has been cited by other articles:

				K. I. Shoghi, R. J. Gropler, T. Sharp, P. Herrero, N. Fettig, Y. Su, M. S. Mitra, A. Kovacs, B. N. Finck, and M. J. Welch Time Course of Alterations in Myocardial Glucose Utilization in the Zucker Diabetic Fatty Rat with Correlation to Gene Expression of Glucose Transporters: A Small-Animal PET Investigation J. Nucl. Med., August 1, 2008; 49(8): 1320 - 1327. [Abstract] [Full Text] [PDF]

				T. R. DeGrado, M. T. Kitapci, S. Wang, J. Ying, and G. D. Lopaschuk Validation of 18F-Fluoro-4-Thia-Palmitate as a PET Probe for Myocardial Fatty Acid Oxidation: Effects of Hypoxia and Composition of Exogenous Fatty Acids J. Nucl. Med., January 1, 2006; 47(1): 173 - 181. [Abstract] [Full Text] [PDF]

				E. O. McFalls, B. Murad, D. Her, J.-S. Liow, R. Kelly, D. Marx, J. Sikora, and H. B. Ward Repetitive Supply-Demand Ischemia with Dobutamine Increases Glucose Uptake in Postischemic and Remote Myocardium J. Nucl. Med., January 1, 2003; 44(1): 85 - 91. [Abstract] [Full Text] [PDF]

				P. Herrero, T. L. Sharp, C. Dence, B. M. Haraden, and R. J. Gropler Comparison of 1-11C-Glucose and 18F-FDG for Quantifying Myocardial Glucose Use with PET J. Nucl. Med., November 1, 2002; 43(11): 1530 - 1541. [Abstract] [Full Text] [PDF]

				S. L. Bacharach and S. K. Sundaram 18F-FDG in Cardiology and Oncology: The Bitter with the Sweet J. Nucl. Med., November 1, 2002; 43(11): 1542 - 1544. [Full Text] [PDF]

				M. M. Graham, M. Muzi, A. M. Spence, F. O'Sullivan, T. K. Lewellen, J. M. Link, and K. A. Krohn The FDG Lumped Constant in Normal Human Brain J. Nucl. Med., September 1, 2002; 43(9): 1157 - 1166. [Abstract] [Full Text] [PDF]

				A. Tardif, N. Julien, A. Pelletier, G. Thibault, A. K. Srivastava, J.-L. Chiasson, and L. Coderre Chronic exposure to beta -hydroxybutyrate impairs insulin action in primary cultures of adult cardiomyocytes Am J Physiol Endocrinol Metab, December 1, 2001; 281(6): E1205 - E1212. [Abstract] [Full Text] [PDF]

				K. Mather, M. Laakso, S. Edelman, G. Hook, and A. Baron Evidence for physiological coupling of insulin-mediated glucose metabolism and limb blood flow Am J Physiol Endocrinol Metab, December 1, 2000; 279(6): E1264 - E1270. [Abstract] [Full Text] [PDF]

				H. E. Botker, H. Wiggers, M. Bottcher, J. S. Christiansen, T. T. Nielsen, A. Gjedde, and O. Schmitz Short-term effects of growth hormone on myocardial glucose uptake in healthy humans Am J Physiol Endocrinol Metab, June 1, 2000; 278(6): E1053 - E1059. [Abstract] [Full Text] [PDF]