THE ROLE OF FE2-INDUCED LIPID-PEROXIDATION OF LIPOSOME MEMBRANES( IN HYPOCHLORITE)

The participation of iron ions in hypochlorite (OCl-)-induced lipid pe roxidation (LPO) was investigated by the chemiluminescence (CL) method . The addition of Fe2+ to OCl- water solutions was shown to be accompa nied by CL flash similarity to the well - known Fenton's reaction (H2O 2 + Fe2+) generating hydroxyl (OH.) radicals. Data obtained pointed to the fact that the reaction of Fe2+ with OCl- leads to free radical fo rmation: these radicals, possibly, OH., may initiate free radical LPO. However, in the model system under study (phospholipid liposomes + Fe 2+ + OCl-), this reaction did not contribute to liposome membrane LPO as compared with the Fe2+-induced LPO itself. Nevertheless, preincubat ion of liposomes with OCL(-) produced a considerable LPO product accum ulation increasing with the increase of OCL(-) concentration and in in cubation time. The subsequent Fe2+ addition was followed by an increas ed CL flash indicating that Fe ions converted OCl--induced LPO product s into free radical intermediates initiating new LPO chains. The react ion; of Fe2+ with primary LPO products (<<chain branching>> reaction) was concluded to play an important role in OCl--induced LPO.