Testing the "rate of living" model: further evidence that longevity and metabolic rate are not inversely correlated in Drosophila melanogaster

• Published in: Journal of applied physiology (1985) Vol. 97; no. 5; pp. 1915 - 1922
• Main Authors: Van Voorhies, Wayne A, Khazaeli, Aziz A, Curtsinger, James W
• Format: Journal Article
• Language: English
• Published: Bethesda, MD Am Physiological Soc 01.11.2004; American Physiological Society
• Subjects: Animals; Biological and medical sciences; Carbon Dioxide - metabolism; Drosophila melanogaster; Drosophila melanogaster - drug effects; Drosophila melanogaster - growth & development; Drosophila melanogaster - metabolism; Female; Food Deprivation - physiology; Fundamental and applied biological sciences. Psychology; Insecta; Insects; Invertebrates; Life cycle. Embryology. Development; Longevity; Male; Metabolism; Models, Biological; Nitrogen - pharmacology; Oxygen Consumption; Physiology. Development; Restraint, Physical; Correlation; Senescence; Insecta; Longevity; Metabolism; Drosophilidae; respiratory quotient; Arthropoda; Models; aging; Invertebrata; Drosophila melanogaster; Diptera
• ISSN: 8750-7587; 1522-1601
• DOI: 10.1152/japplphysiol.00505.2004

1 Molecular Biology Program, New Mexico State University, Las Cruces, New Mexico 88003-8001; and 2 Department of Ecology, Evolution, and Behavior, University of Minnesota, St. Paul, Minnesota 55108 Submitted 11 May 2004 ; accepted in final form 24 June 2004 In a recent study examining the relationship between longevity and metabolism in a large number of recombinant inbred Drosophila melanogaster lines, we found no indication of the inverse relationship between longevity and metabolic rate that one would expect under the classical "rate of living" model. A potential limitation in generalizing from that study is that it was conducted on experimental material derived from a single set of parental strains originally developed over 20 years ago. To determine whether the observations made with those lines are characteristic of the species, we studied metabolic rates and longevities in a second, independently derived set of recombinant inbred lines. We found no correlation in these lines between metabolic rate and longevity, indicating that the ability to both maintain a normal metabolic rate and have extended longevity may apply to D. melanogaster in general. To determine how closely our measurements reflect metabolic rates of flies maintained under conditions of life span assays, we used long-term, flow-through metabolic rate measurements and closed system respirometry to examine the effects of variables such as time of day, feeding state, fly density, mobility of the flies, and nitrogen knockout on D. melanogaster metabolic rate. We found that CO 2 production estimated in individual flies accurately reflects metabolic rates of flies under the conditions used for longevity assays. aging; respiratory quotient Address for reprint requests and other correspondence: W. Van Voorhies, Molecular Biology Program, MSC 3MLS, New Mexico State Univ., Las Cruces, NM 88003-8001 (E-mail: wvanvoor{at}nmsu.edu ).