Inhalation of High Doses of Gaseous Nitric Oxide in HIV Infection

The therapeutic effect of high-dose inhalation of nitrogen oxide gas (at a NO concentration of at least 1000 ppm) in two HIV-infected patients was demonstrated. Inhaled NO therapy led to a rapid decrease in viral load to an undetectable level, which persisted even after the period of analytical interruption of treatment. It was assumed that the relief of HIV infection was due to nitrosonium cations NO⁺ formed in the blood from neutral NO molecules. The subsequent conversion of NO⁺ cations in their reaction with hydroxyl anions into nitrite anions was prevented by the binding of NO⁺ cations with chlorine anions and the formation of nitrosochloride in the blood. The entry of this agent from the blood into cells and tissues provided the transfer of NO⁺ cations into them. The interaction of nitrosochloride with thiols could lead to the appearance of corresponding S-nitrosothiols in cells and tissues as NO donors.