Table 4.
The cardiomyocyte morphometry in atria of human ageing heart (mean ± SE)
| Cardiomyocyte | Newborns | Children | Adults |
|---|---|---|---|
| Diameter (μm) | 7.4 ± 1.8 | 12.7 ± 2.1* | 13.5 ± 2.3*,† |
| Cardiomyocyte cross-sectional area (μm2) | 65.1 ± 14.3 | 166.6 ± 55* | 188.3 ± 68.4* |
| Nucleus area (%)‡ | 27.1 ± 4.1 | 21.6 ± 5.8§ | 23 ± 5.3§ |
| Euchromatin area (%) | 68 ± 9.7 | 62 ± 9.5§ | 65.3 ± 8.2§ |
| Mitochondrial area (%) | 31 ± 4.9 | 35.1 ± 7.5* | 27.3 ± 5.1§ |
| Myofibril area (%) | 47 ± 8 | 58 ± 8* | 57 ± 12* |
| Sarcomere length (μm) | 1.7 ± 0.1 | 1.4 ± 0.1§ | 1.4 ± 0.3§ |
| Caveolae (no/μm)¶ | 1.2 ± 0.5 | 0.8 ± 0.2§ | 0.3 ± 0.02§ |
| Lipofuscin granules (%) | – | – | 3.5 ± 0.4 |
*
The number significantly increased in children and adults compared with newborns (P < 0.01).
†
The number of cells significantly increased in adults compared with children (P < 0.05).
‡
Cross-sectional area of CMs.
§
The number significantly decreased in children and adults compared with newborn group (P < 0.05).
¶
Number per μm of plasma membrane length.