Table 2.
Average cross-sectional area of single skeletal muscle fibers from controls and heart failure patients.
Controls | Heart failure | # of fibers (control/heart failure) | |
---|---|---|---|
All fibers (μm2) | 5880 ± 145 | 6824 ± 160 * | 194/200 |
Fibers with detectable MHC content (μm2) | 5916 ± 159 | 6748 ± 169 * | 169/161 |
MHC I fibers (μm2) | 6613 ± 242 | 6538 ± 247 | 88/75 |
MHC IIA fibers (μm2) | 5422 ± 210 | 7419 ± 305 * | 50/46 |
MHC IIA/X fibers (μm2) | 4450 ± 193 | 6091 ± 347 * | 22/29 |
Data are mean ± SE and reflect the average cross-sectional area from top and side diameter measurements every 250 μm along the length of each fiber. Fibers with detectable MHC include only those with band densities greater than background, whereas the All fibers includes those with band densities equal to or less than background. There were too few MHC IIX and I/IIA fibers to permit comparisons between groups.
, P<0.01.