Nitric oxide: modulation of the pulmonary circulation

Nitric oxide (NO) is synthetized throughout the body by the enzyme NO synthase (NOS), cyclic GMP transduction pathway causes pulmonary vasodilatation anti-platelets aggregation and inhibition of leukocyte adhesion. Inducible NOS is expressed in leukocytes in response to a variety of inflammatory stimuli and can be inhibited by corticosteroids. Inhaled NO is a selective pulmonary vasodilator. In USA inhaled NO was approved by FDA for hypoxemic respiratory failure in infants and children. In adults it may be useful in various clinical therapy: pulmonary hypertension, lung transplantation, ARDS but new clinical investigations are necessary.