Use and Abuse of Hemoglobin
Aside from oxygen transport, hemoglobin can bind and carriage added molecules like nitric oxide and carbon monoxide. Nitric oxide affects the walls of claret vessels, causing them to relax. This in about-face reduces the claret pressure. Recent studies accept apparent that nitric oxide can bind to specific cysteine residues in hemoglobin and aswell to the band in the heme groups, as apparent in PDB access 1buw .
Thus, hemoglobin contributes to the adjustment of claret burden by distributing nitric oxide through blood. Carbon monoxide, on the added hand, is a baneful gas. It readily replaces oxygen at the heme groups, as apparent in PDB access 2hco and abounding others, basic abiding complexes that are difficult to remove. This corruption of the heme groups blocks accustomed oxygen bounden and transport, airless the surrounding cells.