Submitted by Dr. Tamer Fouad, M.D.
Hypochlorous acid
Activated polymorphonuclear
cells produce HOCl as a major bactericidal agent. It is generated by
the action of myeloperoxidase on chloride ions in the presence of H2O2.
H2O2 +
Cl-
? HOCl + OH-
This reaction occurs in the
neutrophils phagocytic vacuole after fusion with the myeloperoxidase-containing
lysosomal vesicles.
Hypochlorous acid can cross
cell membranes and, in the presence of transitional metal ions,
generate hydroxyl radicals (Aruoma,
1994). Highly reactive hydroxyl radicals can be formed from HOCl/OCl-
on reaction with reductants that are one-electron donors. Important
examples include superoxide radicals and ferrous iron:
HOCl + O2?-
? ?OH + Cl- + O2
HOCl + Fe2+
? ?OH + Cl- + Fe3+
HOCl has been shown to be
capable of initiating lipid peroxidation (Panasenko
et al. 1995), combining with H2O2 to
damage DNA and DNA repair processes (VanRensburg
et al. 1992) and altering intracellular free Ca2+ and
pH (Kuroda et al. 1995). It may contribute to tissue damage during
the inflammatory process. This latter event may result from the
activation of collagenases or the inactivation of alpha-1
antiproteinase (Ching et al.
1994).
|
|
|
|
Are you a doctor or a nurse?
Do you want to join the Doctors Lounge online medical community?
Participate in editorial activities (publish, peer review, edit) and
give a helping hand to the largest online community of patients.
Click on the link below to see the requirements:
Doctors Lounge Membership
Application |
|
send
to a friend
printer
friendly version
