Effects of aging on respiration, ATP levels and calcium transport in rat liver mitochondria. Response to theophylline.

The concept that aging results in an impairment of mitochondrial biochemistry has been tested on organelles isolated from the liver of 3-4-month-old and 24-month-old rats of the Wistar strain. Our data suggest that aging results in significant decreases in succinate-supported respiration, ATP levels and calcium uptake. When theophylline was added to the incubation mixture, both respiration and calcium uptake were depressed in approximately the same proportion in the mitochondria from old rats, although the mitochondrial ATP of young animals was significantly decreased by this substance.