Platelet Activating Factor (PAF) is a biologically active phospholipid, which exerts primarily proinflammatory activities by specifically signaling through G-protein-coupled receptors on platelets, neutrophils, and monocytes. Platelet activating factor acetylhydrolase (PAF-AH) is a secreted protein that mediates PAF activity by specifically catalyzing hydrolysis of the "sn2" ester bond, resulting in the conversion of PAF to the biologically inactive lyso-PAF. PAF-AH can also interact with LDL (low density lipoprotein) particles to induce the hydrolysis of LDL associated, oxidized phospholipids, generating lysophosphatidylcholine (lyso-PC) and other lysophospholipids. High levels of PAF-AH in plasma can be an indication of resistant hypertension. Polymorphism in PAF-AH gene at A379V might be linked with ischemic stroke susceptibility.
