Effects of CN-100 on the functions of rat polymorphonuclear leukocytes

We studied the effects of CN-100 on the functions of rat polymorphonuclear leukocytes (PMN) in vitro. CN-100 showed the inhibitory effects of superoxide production and luminol dependent chemiluminescence induced by opsonized zymosan (OZ) or N-formyl-methionyl-leucyl-phenylalanine (FMLP) in PMN, and its inhibitory activity was almost equipotent to that of indomethacin and more than that of pranoprofen. Preincubation of cytochalasin E-treated PMN with CN-100, indomethacin and pranoprofen resulted in dose-dependent inhibition of lysosomal enzyme release elicited by OZ or FMLP, but pranoprofen was less potent than CN-100 and indomethacin. CN-100 and indomethacin inhibited the increase of intracellular calcium in Furall loaded PMN stimulated by FMLP. The inhibitions by both agents were reversible. These findings indicated that the reversible interaction between CN-100 and PMN membrane inhibit signal transduction starting from intracellular calcium mobilization in PMN and suppress many PMN' s functions. These results suggest that CN-100 has an inhibitory activity on PMN function which is as potent as that of indomethacin.