The effect of age on serum proteins in mice

The relation of serum protein levels to age was investigated in the Swiss mouse. The present study demonstrates for the first time a dynamic age-dependent relationship between the various serum proteins. Total serum protein displayed a nonlinear change, decreasing from 10 to 136 days of age and thereafter increasing with advancing age with a peak at 465 days of age. Globulin concentration increased throughout the life span while albumin decreased for the first 136 days, after which it rose and peaked at 465 days of age. The relative percentage of each serum protein undergoes a significant non-constant, non-linear and non-quadratic change with increasing age. The patterns displayed by the various globulin fractions are strikingly similar to each other and tend to be inversely related to the pattern displayed by albumin. The relative percentage of each globulin fraction displayed a biphasic change with a peak at 200 days and a trough at 500 days of age.