european college of sport science

OP-PH07 Physiology 7
CARDIAC STEM CELL ACTIVATION AND ENSUING MYOGENESIS AND ANGIOGENESIS CONTRIBUTE IN CARDIAC AD-
APTATION TO INTENSITY-CONTROLLED EXERCISE TRAINING.
WARING, C., TORELLA, D., ELLISON, G.
LIVERPOOL JOHN MOORES UNIVERSITY
Traditionally, it was thought that exercise improved cardiac function by increasing myocardial mass and contractility through physiological
hypertrophy of existing myocytes and enhanced coronary perfusion. Recent data on myocardial cell homeostasis and the identification
of cardiac stem cells (CSCs), in the adult mammalian heart, could challenge this concept. We sought to assess if CSC activation and
ensuing myocyte and capillary formation participates in cardiac remodeling induced by intensity-controlled exercise training. To this aim,
42 male Wistar rats (226.5±1.5g) were exercised at either a Low (LI; 55-60% VO2 max) or High (HI; 85-90% VO2 max) intensity for 30
mins/day, 4 days/week for up to 4 weeks on motorized treadmills. Fifteen untrained rats acted as age-matched sedentary controls
(CTRL). To track myocardial proliferation, BrdU was administered (i.p.) twice daily. Hearts were arrested in diastole and the Left Ventricles
(LV) were processed for immunohistochemistry and confocal microscopy analysis. Results showed an increase (P