Absence of activation of proteolytic enzymes by extracorporeal shock waves

The mechanism of tissue damage by extracorporeal shock wave lithotripsy has not been clarified, but proteolytic enzymes are known to play an important role in tissue breakdown in response to other types of injury. Screening tests for activation of the proteolytic enzymes kallikrein, plasmin, trypsins 1 and 2, and granulocyte elastase therefore were performed for 4 to 5 hours in 14 dogs after unilateral treatment with 1500 or 2000 extracorporeal shock waves under anesthesia and vigorous hydration. We also studied the activity of the proenzymes prekallikrein, plasminogen, and prothrombin and three plasma protease inhibitors (kallikrein inhibitor, antiplasmin, and antithrombin III). Blood from both renal veins (treated and control kidneys) and the aorta and tissue samples of the injured renal parenchyma and corresponding areas of the control kidneys revealed no proteolytic enzyme activation by the shock waves and no decline in the activities of proenzymes and enzymes inhibitors. Significant proteolysis does not seem to play a part in the tissue injury induced by extracorporeal shock wave lithotripsy.