Nitric oxide (NO) reacts with superoxide (O2•−) to form a highly reactive nitrogen species that causes tyrosine nitration and cellular damage. What is the name of this reactive species?
- A Nitrogen dioxide
- B Peroxynitrite ✓
- C Nitrite
- D Nitrate
Correct answer: B. Peroxynitrite
Explanation
Nitric oxide reacts with superoxide to form peroxynitrite (ONOO−), a potent oxidant and nitrating agent. Nitrogen dioxide is formed from NO oxidation but not directly from superoxide. Nitrite and nitrate are stable end-products of NO metabolism, not the reactive intermediate formed by this specific reaction.
Reference: Robbins and Cotran Pathologic Basis of Disease, 10th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
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