The increased circulating CD16+ monocytes and its intracellular TNFα/NFκB/iNOS/MCP-1 levels, circulating chemokines (MCP-1)/adhesion molecules (sICAM-1) levels were associated with the pulmonary macrophages recruitment in our rat cirrhotic rats with experimental HPS. Here, NOS2 is linked to Hermansky-Pudlak syndrome.