The involvement of polymorphonuclear leukocytes in the pathogenesis of bronchopneumonia in calves. III. Granulocyte activation by platelets.

The influence of platelets and platelet lysate on superoxide anion production and beta-glucuronidase release from neutrophils was investigated. Neither the suspension of unstimulated platelets from healthy calves nor its lysate had any influence on O2- production and enzyme release On the other hand, a great rise in superoxide anion production and beta-glucuronidase release was observed in the case of platelets from bronchopneumonic calves. It is suggested that platelets of bronchopneumonic calves can activate polymorphonuclear leukocytes, causing their degranulation and aggravating superoxide anion production.