Age-related changes in the metabolism of tendon cells

Rabbit tendon cells undergo considerable metabolic change from birth to old age. Aerobic glycolysis is the main energy source during the first three months of life, whereas from this age onwards cell respiration gradually decreases and finally ceases at one year of age. In young tendons glucose-1-14C oxidation is high, indicating an active pentose-monophosphate shunt. In old tendons glucose-6-14C is not a precursor for lactate whereas alanine-U-14C is an excellent precursor. Anaerobic glycolysis, which has the same activity throughout the whole tendon lifespan, may be an alternative to aerobic glycolysis at all ages.