Activity of two components of serum ribonuclease under conditions of physical exercise.

Serum ribonuclease activity before and after physical exercise in healthy persons was estimated. It is found that a work load of 6000 kgm/5 min increased ribonuclease activity measured at pH 8.5 and decreased the activity of the same enzyme measured at pH 7.0 in the presence of Zn SO4. The observed changes were more pronounced in untrained than in trained persons.