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3. CYP 450 or Cyt P-450: major pathway for hydroxylation of
xenobiotics. Supply of NADPH is critical for liver microsomal cyt
P-450.
4. Phagocytosis of microorganisms esp bacteria, foreign particles
etc by Neutrophils & Macrophages: imp defense mechanism.
a. Oxygen dependent system- MPO [myeloperoxidase system]-
most potent
NADPH OXIDASE [needs NADPH] in WBC cell memb, converts O2
into Superoxide FR [Respiratory burst]→Superoxide is
converted by SOD [superoxide dismutase] into H2O2 →lysosomal
MPO converts it to hypochlorous acid HOCl·→ kills bacteria
NADPH OXIDASE deficiency- Chronic granulomatosis
b. Oxygen independent system- pH changes in phagolysosomes and
lysosomal enzymes- destroy pathogens
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