Table I.

Effects of PKG and PI3K inhibitors on the release of enzymes from three different classes of neutrophil granulesa

% InhibitionRp-8-Br-PET-cGMPLY294002
50 μM100 μM5 μM10 μM
β-Glucuronidase15.8 ± 4.147.2 ± 5.227.8 ± 4.153.8 ± 4.4
LTF23.7 ± 0.228.6 ± 3.415.7 ± 1.132.7 ± 1.3
MMP-927.6 ± 4.332.8 ± 2.638.9 ± 4.848.6 ± 3.8
  • a Peripheral blood neutrophils were purified as described in Materials and Methods. Isolated human neutrophils were preincubated with 10 μM cytochalasin B with or without inhibitors. The cells were then stimulated with 100 nM fMLF for 10 min at 37°C, and the amount of released enzymes was determined based on enzymatic cleavage of fluorogenic substrate (for β-glucuronidase) or by ELISA (for LTF and MMP-9), as detailed in Materials and Methods. Data presented are percentage of inhibition and are means ± SEM from three independent experiments.