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

This Article Full Text Full Text (PDF) All Versions of this Article: 285/5/H2158    most recent 00086.2003v1 Alert me when this article is cited Alert me if a correction is posted Citation Map Services Email this article to a friend Similar articles in this journal Similar articles in Web of Science 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 Web of Science (18) Citing Articles via Google Scholar Google Scholar Articles by Soto, P. F. Articles by Gropler, R. J. Search for Related Content PubMed PubMed Citation Articles by Soto, P. F. Articles by Gropler, R. J.

Impact of aging on myocardial metabolic response to dobutamine

¹Cardiovascular Division, Department of Internal Medicine, ²Division of Radiological Sciences, Edward Mallinckrodt Institute of Radiology, and ³Division of Biostatistics, Washington University School of Medicine, St. Louis, Missouri 63110

Submitted 17 June 2003 ; accepted in final form 14 July 2003

In humans, under resting conditions there is an age-related decrease in myocardial fatty acid utilization (MFAU) and oxidation (MFAO) and a relative increase in myocardial glucose utilization (MGU). The impact of age on an individual's myocardial metabolic response to catecholamines is not well defined. Sixteen younger (mean age, 26 ± 5 yr) and 14 older (mean age, 69 ± 4 yr) volunteers underwent positron emission tomography to measure myocardial blood flow, myocardial oxygen consumption (MO₂), MFAU, MFAO, and MGU both under resting conditions and during dobutamine infusion. In response to dobutamine administration, the rate-pressure product, myocardial blood flow, and MO₂ measurements increased by similar amounts in both groups. No age-related differences were noted in the responses of plasma insulin, glucose, fatty acid, or lactate levels to dobutamine. With dobutamine infusion, MFAU and MFAO increased by a similar extent in both younger and older volunteers (age/dobutamine interactions, P = 0.62 and 0.75, respectively). In contrast, MGU increased with dobutamine administration in the younger (from 149 ± 71 to 209 ± 78 nmol · g^–1 · min^–1; P = 0.04) but not in the older (from 235 ± 147 to 176 ± 84 nmol · g^–1 · min^–1; P = 0.23; age/dobutamine interaction, P = 0.03) group. With dobutamine infusion, hearts in both younger and older volunteers responded by increasing their MFAU and MFAO values. Whereas younger hearts also responded with an increase in MGU, older hearts did not. Although the clinical significance of these findings awaits further study, these results may partially explain the impaired contractile reserve and the increased incidence of cardiovascular disease in older individuals.

fatty acids; glucose; oxidation; heart; catecholamine

This article has been cited by other articles:

				P. F. Soto, P. Herrero, K. B. Schechtman, A. D. Waggoner, J. M. Baumstark, A. A. Ehsani, and R. J. Gropler Exercise training impacts the myocardial metabolism of older individuals in a gender-specific manner Am J Physiol Heart Circ Physiol, August 1, 2008; 295(2): H842 - H850. [Abstract] [Full Text] [PDF]

				P. Herrero, C. S. Dence, A. R. Coggan, Z. Kisrieva-Ware, P. Eisenbeis, and R. J. Gropler L-3-11C-Lactate as a PET Tracer of Myocardial Lactate Metabolism: A Feasibility Study J. Nucl. Med., December 1, 2007; 48(12): 2046 - 2055. [Abstract] [Full Text] [PDF]

				S. A. Cooper, A. Whaley-Connell, J. Habibi, Y. Wei, G. Lastra, C. Manrique, S. Stas, and J. R. Sowers Renin-angiotensin-aldosterone system and oxidative stress in cardiovascular insulin resistance Am J Physiol Heart Circ Physiol, October 1, 2007; 293(4): H2009 - H2023. [Abstract] [Full Text] [PDF]

				I. Luptak, J. Yan, L. Cui, M. Jain, R. Liao, and R. Tian Long-Term Effects of Increased Glucose Entry on Mouse Hearts During Normal Aging and Ischemic Stress Circulation, August 21, 2007; 116(8): 901 - 909. [Abstract] [Full Text] [PDF]

				P. Herrero, J. Kim, T. L. Sharp, J. A. Engelbach, J. S. Lewis, R. J. Gropler, and M. J. Welch Assessment of Myocardial Blood Flow Using 15O-Water and 1-11C-Acetate in Rats with Small-Animal PET J. Nucl. Med., March 1, 2006; 47(3): 477 - 485. [Abstract] [Full Text] [PDF]

				K. L. King, I. C. Okere, N. Sharma, J. R. B. Dyck, A. E. Reszko, T. A. McElfresh, J. Kerner, M. P. Chandler, G. D. Lopaschuk, and W. C. Stanley Regulation of cardiac malonyl-CoA content and fatty acid oxidation during increased cardiac power Am J Physiol Heart Circ Physiol, September 1, 2005; 289(3): H1033 - H1037. [Abstract] [Full Text] [PDF]