Plasma myeloperoxidase level and polymorphonuclear leukocyte activation inhorses suffering from large intestinal obstruction requiring surgery: Preliminary results

Myeloperoxidase (MPO) is a specific enzyme of neutrophil azurophilic granul es with a strong oxidative activity. Thanks to a radioimmunoassay of equine myeloperoxidase, the: authors have observed a significantly higher plasma level of MPO in horses operated for strangulation obstruction of the large intestine (n = 6) than in horses suffering from a non-strangulating displac ement of the large intestine (n = 9), For the 2 groups, 3 phases Were disti nguished: reception (P1), intensive care (P2) and terminal phase (P3). The mean peak values of MPO for these phases were 121.6 ng/mL (P1), 168.6 ng/mL (P2), and 107.0 ng/mL (P3) for the non-strangulating group, and 242.6 ng/m L (P1); 426.0 ng/mL (P2), and 379.5 ng/mL (P3) for the strangulation group. The variations of the mean peak values of plasma MPO were significantly di fferent between the 2 groups and between the different phases. A significan t increase of the least square means of MPO was observed between P1 and P2, A significant decrease of the least square means of the number of circulat ing leukocytes was observed between P1 and P3, Polymorphonuclear neutrophil activation could play a major role in the pathogenesis of acute abdominal disease and endotoxic shock.