We found a match
Your institution may have rights to this item. Sign in to continue.
- Title
Effect of voluntary exercise on number and volume of cardiomyocytes and their mitochondria in the mouse left ventricle.
- Authors
Eisele, Judith; Schaefer, Inga-Marie; Nyengaard, Jens Randel; Post, Heiner; Liebetanz, David; Brüel, Annemarie; Mühlfeld, Christian
- Abstract
Voluntary exercise (VE) has a beneficial influence on the heart and mean lifespan. The present study evaluates structural adaptations of cardiomyocytes and their mitochondria due to VE by new, unbiased stereological methods. Female, 7–9-week-old mice were randomly assigned to a control (CG, n = 7) or VE group (EG, n = 7). EG animals were housed in cages with free access to a running wheel and had a mean running distance of 6.7 (1.8) km per day. After 4 weeks, the hearts of all mice were processed for light and electron microscopy. We estimated the number and volume of cardiomyocytes by the disector method and the number and volume of mitochondria by estimation of the Euler number. In comparison to CG, VE did not have an effect on the myocardial volume of the left ventricle (CG: 93 (10), EG: 103 (17) (mm3)), the number of cardiomyocytes (CG: 2.81 (0.27), EG: 2.82 (0.43) (×106)) and their number-weighted mean volume. However, the composition of the cardiomyocytes changed due to VE. The total volume of mitochondria (CG: 21.8 (4.9), EG: 32.2 (4.3) (mm3), P < 0.01) and the total number (CG: 3.76 (0.44), EG: 7.02 (1.13) (×1010), P < 0.001) were significantly higher in EG than in CG. The mean number-weighted mitochondrial volume was smaller in EG than in CG ( P < 0.05). In summary, VE does not alter ventricular volume nor cardiomyocyte volume or number but the oxidative capacity of cardiomyocytes by an increased mitochondrial number and total volume in the left ventricle. These structural changes may participate in the beneficial effects of VE.
- Subjects
EXERCISE; HEART cells; LONGEVITY; MITOCHONDRIA; EULER characteristic
- Publication
Basic Research in Cardiology, 2008, Vol 103, Issue 1, p12
- ISSN
0300-8428
- Publication type
Article
- DOI
10.1007/s00395-007-0684-x