Ea. Puchninaartushenko et al., SUBLETHAL DOSES OF EXOGENOUS HYDROGEN-PEROXIDE PRIME HUMAN NEUTROPHILS TO FORMYL PEPTIDE, Agents and actions, 39, 1993, pp. 30000192-30000194
Hydrogen peroxide (H2O2) is an oxidative agent important in inflammati
on and ischemia. Neutrophils (PMNs) are a main source of H2O2 in the i
nflammatory focus. However, after recruitment into the inflammatory or
ischemic zone of the heart, the PMN itself might serve as a target fo
r exogenous H2O2. In the present work we found that PMNs are very resi
stant to the cytotoxic action of H2O2 (LD50 for PMNs is about 30-50 mM
, whereas for endothelial cells it is about 200-300 muM). Unexpectedly
, treatment of PMNs by H2O2 at a sublethal dose of 10 mM leads to a su
bsequent increase in the generation of superoxide anion in response to
the chemoattractant peptide FMLP (twofold increase in O2- generation
30 min after treatment by H2O2 as compared with nontreated control cel
ls). H2O2 itself does not induce O2- generation by PMNs. Therefore, an
y H2O2 that accumulated in the inflammatory or ischemic zone might alt
er the functional activity of PMNs and prime them to subsequent agonis
t activation.