Description
Introduction: Visfatin, an adipokine that is highly enriched in the visceral fat, has increased expression level in plasma during the development of obesity, implying its important role in obesity. Visfatin (also known as PBEF and Nampt), a 52 kDa cytoplasmic protein composed of 473-amino acid, expresses primarily in bone marrow, muscle and liver tissue but can also be detected in placenta, lung, kidney and heart tissue. In addition to its role in obesity, visfatin also has other biological functions. Visfatin is a nicotinamide phosphoribosyltransferase (Nampt) enzyme that catalyzes first step in the biosynthesis of NAD from nicotinamide. Visfatin has also been reported to be a cytokine (PBEF) that promotes B cell maturation and inhibits neutrophil apoptosis.
Principle of the Assay: The microtiter plate provided in this kit has been pre-coated with an antibody specific to visfatin. Standards or samples are then added to the appropriate microtiter plate wells with a biotin-conjugated antibody preparation specific for visfatin and Avidin conjugated to Horseradish Peroxidase (HRP) is added to each microplate well and incubated. Then a TMB (3,3',5,5' tetramethyl-benzidine) substrate solution is added to each well. Only those wells that contain visfatin, biotin-conjugated antibody and enzyme-conjugated Avidin will exhibit a change in color. The enzyme-substrate reaction is terminated by the addition of a sulphuric acid solution and the color change is measured spectrophotometrically at a wavelength of 450 nm +/- 2 nm. The concentration of visfatin in the samples is then determined by comparing the O.D. of the samples to the standard curve