Muscle Proteolysis Induced by a Circulating Peptide in Patients with Sepsis or Trauma

Accelerated proteolysis of muscle is characteristic in patients with trauma or sepsis, but its cause is not well understood. Using rat muscle in vitro, we developed a bioassay to compare the proteolytic activity of plasma from 50 patients with trauma or sepsis with that of plasma from 14 normal volunteers and from 15 patients who had undergone "clean" elective surgical procedures. The mean proteolytic activity in the plasma of patients with trauma or sepsis was found to be 190±8.0 per cent of the control value (rat muscle incubated in medium alone), whereas the activity in normal plasma was 124±4.5 per cent (P