A COMPARISON OF THE EFFECTS OF SIGNAL-TRANSDUCTION INHIBITORS ON OXIDATIVE BURST AND DEGRANULATION IN IL-I-BETA STIMULATED BOVINE NEUTROPHILS

There is little information available on IL-1 mediated signal transduc tion in neutrophils from species other than humans. In this study, sig nal transduction pathway inhibitors were used to compare signaling pat hways for the oxidative burst and degranulation in bovine neutrophils stimulated with rBoIL-1 beta. Protein kinase C inhibitors (staurospori ne and chelerythine), DL-propranolol, pertussis toxin (PT), genistein and verapamil significantly inhibited rBoIL-1 beta (10 ng/ml) stimulat ed luminol-dependent chemiluminescence (LDCL) in a dose-dependent mann er, while indomethacin and zileuton had no effect. Propranolol signifi cantly decreased both primary and secondary granule release in respons e to rBoIL-1 beta. Staurosporine enhanced secondary but not primary gr anule release, and PT increased primary and secondary granule release. In addition, propranolol inhibited the shape change induced by rBoIL- 1 beta and zymosan-activated serum, whereas PT markedly decreased the response induced by zymosan-activated serum, but not rBoIL-1 beta. The se findings suggest that rBoIL-1 beta stimulation of the oxidative bur st, degranulation, and shape change of bovine neutrophils are mediated through distinct signal transduction pathways.