Age-related changes of AMP breakdown in chicken heart

The activity of adenylate deaminase, adenylate phosphatase and adenosine deaminase, as well as the endogenous content of adenine nucleotides, was examined in the heart of ageing chickens. In new-born (1-day-old) and young (20-day-old) chickens, AMP degradation in the heart seems to proceed preferentially through deamination, while in adult (1-year-old) through dephosphorylation. Compared with the adult heart, a 2-year-old one exhibits a decline of AMP catabolism. The total adenine nucleotide content and the concentration of ATP are higher in adult and aged chicken hearts, than in new-born and young ones. Adaptive mechanisms might occur in the heart of ageing chickens to ensure an adequate availability of adenine nucleotides.