PAF Acetylhydrolase Inhibitor Screening Assay Kit

Platelet-activating factor (PAF) is a biologically active phospholipid synthesized by a variety of stimulated cells. The biological effects of PAF include activation of platelets, polymorphonuclear leukocytes, monocytes, and macrophages. PAF also increases vascular permeability, decreases cardiac output, induces hypotension, and stimulates uterine contraction.{939} PAF has been implicated in pathological processes, such as inflammation and allergy.{11753} PAF is converted to the biologically inactive lyso-PAF by the enzyme PAF acetylhydrolase (PAF-AH). PAF-AHs are located intra- and extra-cellularly (e.g., cytosolic and plasma). Plasma PAF-AH is highly selective for phospholipids with very short acyl groups at the sn-2 position and is associated with lipoproteins.{2626} Recently, plasma PAF-AH has been linked to atherosclerosis and may be a positive risk factor for coronary heart disease in humans.{11455} The Cayman Chemical PAF Acetylhydrolase Inhibitor Screening Assay uses 2-thio PAF as a substrate for PAF-AH.{3787} Upon hydrolysis of the acetyl thioester bond at the sn-2 position by PAF-AH, free thiols are detected using 5,5'-dithio-bis-(2-nitrobenzoic acid) also known as DTNB or Ellman's reagent. Cayman's PAF-AH Inhibitor Screening assay includes human plasma PAF-AH and is a time saving tool for screening vast numbers of inhibitors.