I det pulmonale system kan nitrogenoxid binde sig til ilt og vand for at danne henholdsvis nitrogendioxid og nitrit, som interagerer med oxyhæmoglobin for at danne methæmoglobin og nitrat.
Within the pulmonary system, nitric oxide can combine with oxygen and water to produce nitrogen dioxide and nitrite, respectively, which interact with oxyhaemoglobin to produce methaemoglobin and nitrate.