Abstract: | Interaction of hemoglobin with hypochlorite (OCI-) induces changes in hemoglobin absorption spectra resulting in Soret band decrease and shift similar to those observed under the action of hydrogen peroxide (H2O2). Hemoglobin decomposition is accompanied by free iron release, as estimated by coloured iron-phenanthroline complex formation. The released iron is catalytically active: the incubation of hemoglobin with H2O2, OCl- or activated neutrophils increases the intensity of H2O2-dependent chemiluminescence of hemoglobin. In both reactions OCl- was more efficient than H2O2. These results show that hemoglobin can serve as a source of catalytically active ("free") iron in the reaction with OCl- and with H2O2. |