Review Article
Interaction of Hydrogen Sulfide with Nitric Oxide in the Cardiovascular System
Figure 2
Simplifying depiction of chemical interaction between H2S and NO. The radical of H2S (HS•) reacts with that of NO (NO•) to generate thionitrous acid (HSNO). In an alternate way, HSNO can be produced by hydrosulfide ion (HS−), an anionic form of H2S, after its reaction with different nitrosating biomolecules. Sodium nitroprusside can also produce HSNO by reacting with H2S. In a further step of reaction, HSNO is acted upon by H2S to produce HNO. HNO may modify the functions of proteins by converting their reactive thiols (thiolates) in cysteine residues to N-hydroxysulfenamide (RSNHOH) or forming disulfide bond between two thiol groups in the near vicinity.