Inconsistencies in the presence of age-associated altered aldolase in the livers of mice

Four experiments employing the same biochemical techniques were carried out on C57BL/6 female mice obtained from two sources. In every experiment there was a statistically significant (P <.001) age associated decrease in the specific activity of aldolase in the cytosols. This decrement was the result of a decrease in the enzymatic activity rather than an increase in the protein content of the cytosols of livers of old animals. However, only in one experiment was there also a decrease in the specific activity of the purified preparations. In this experiment the decrease in the specific activity of aldolase in the cytosol was approximately 40% whereas in the other experiments it was approximately 20%. Examinations of the liver and body weights or the protein content of the cytosols indicate no age changes which may account for the age decrement in the specific activities of aldolase of the purified preparations.