The Sound of Evolution
Amyl nitrite
Mechanism of action:
Amyl nitrite is an organic nitrite ester. It is rapidly decomposed in the body to generate nitric oxide (NO), which activates guanylate cyclase in smooth muscle cells and promotes cyclic GMP (cGMP) production. cGMP lowers intracellular calcium concentration, leading to vascular smooth muscle relaxation. In addition, amyl nitrite can oxidize hemoglobin iron from Fe²⁺ to Fe³⁺, forming methemoglobin, which can bind cyanide ions to form cyanmethemoglobin and thereby reduce cyanide's affinity for cytochrome c oxidase.
Reference(s):
Badejo AM Jr et al. (2010). Mitochondrial aldehyde dehydrogenase mediates vasodilator responses of glyceryl trinitrate and sodium nitrite in the pulmonary vascular bed of the rat. Am J Physiol Heart Circ Physiol.