Cu (II) Protoporphyrin IX does not inhibit heme oxygenase (the enzyme that catalyzes the conversion of heme to biliverdin in the heme degradation pathway) and is used as a negative control for Zn (II) Protoporphyrin (an inihibitor of heme oxygenase). Heme oxygenase has been implicated in tumor cell resistance to chemotherapy, reduction of free radical formation and inflammation, and associated with vascular repair.
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