Frontiers in Physiology | |
Greater glucose uptake heterogeneity in knee muscles of old compared to young men during isometric contractions detected by [18F]-FDG PET/CT | |
Brian L Tracy1  John H Kindred1  John-Michael eBenson1  Thorsten eRudroff1  Kari K Kalliokoski2  | |
[1] Colorado State University;University of Turku and Turku University Hospital; | |
关键词: Aging; Glucose; computed tomography; positron emission tomography; Muscle Volume; | |
DOI : 10.3389/fphys.2014.00198 | |
来源: DOAJ |
【 摘 要 】
We used positron emission tomography/computed tomography (PET/CT) and [18F]-FDG to test the hypothesis that glucose uptake (GU) heterogeneity in skeletal muscles as a measure of heterogeneity in muscle activity is greater in old than young men when they perform isometric contractions.Six young (26 ± 6 yrs) and six old (77 ± 6 yrs) men performed two types of submaximal isometric contractions that required either force or position control.[18F]-FDG was injected during the task and PET/CT scans were performed immediately after the task.Within-muscle heterogeneity of knee muscles was determined by calculating the coefficient of variation (CV) of GU in PET image voxels within the muscles of interest.The average GU heterogeneity (mean ± SD) for knee extensors and flexors was greater for the old (35.3 ± 3.3 %) than the young (28.6 ± 2.4 %) (P = 0.006).Muscle volume of the knee extensors were greater for the young compared to the old men (1016 ± 163 vs. 598 ± 70 cm3, P= 0.004).In a multiple regression model, knee extensor muscle volume was a predictor (partial r = - 0.87; P = 0.001) of GU heterogeneity for old men (R2 = 0.78; P < 0.001), and MVC force predicted GU heterogeneity for young men (partial r = - 0.95, P < 0.001).The findings demonstrate that glucose uptake is more spatially variable for old than young men and especially so for old men who exhibit greater muscle atrophy.
【 授权许可】
Unknown