This enzyme immunoassay (EIA) kit is a stable and convenient assay system for peptide YY (PYY). PYY was isolated initially by Tatemoto et al. (1980 ) from the extract of pig duodenum and shown to be a polypeptide consisting of 36 amino acid residues. PYY is homologous to pancreatic polypeptide (PP) and neuropeptide Y (NPY). PYY is localized mainly in endocrine cells in the intestine (ileum, colon, and rectum) showing an inhibitory action on contraction of the gastrointestinal tract and on secretion of pancreatic and gastric juice. PYY is released by taking diet. The PYY level decreases after resection of the intestine possibly are due to the decrease in number of the endocrine cells secreting PYY. The EIA kit is prepared by using synthetic mouse/rat PYY (3-36) as standard antigen and biotinylated mouse/rat PYY (3-36) as labeled antigen. The kit contains specific polyclonal antibody recognized to the amino acid sequence of Mouse/rat PYY. The mouse/rat PYY sequence:
This EIA kit is used for quantitative determination of mouse/rat PYY (1-36) and mouse/rat PYY (3-36) in mouse/rat plasma or serum samples. The kit is characterized for sensitive quantification, high specificity and no influences with other components in samples and needlessness of sample pre-treatment. PYY standard used in the kit is a highly purified synthetic product (purity: higher than 98%).
The EIA kit shows 100% cross reactivity to mouse/rat PYY (3-36) and 115% to mouse/rat PYY (1-36). Cross reactivity was not observed in the assay range with mouse/rat NPY that has similar amino acid sequence with mouse/rat PYY. No cross reactivity with GLP-1 (7-36)-NH2, GLP-1 (1-37), and rat GLP-2 were observed.
This EIA kit for determination of PYY in mouse/rat plasma or serum samples is based on a competitive enzyme immunoassay using the combination of antibody to mouse/rat PYY and biotin–avidin affinity system. The 96 wells plate is coated with goat anti rabbit IgG, to which biotin labeled antigen, standard antigen or samples and rabbit anti mouse/rat PYY antibody are added for competitive immunoreaction. After incubation and plate washing, horse radish peroxidase (HRP) labeled streptavidin (SA) is added to form HRP labeled SA-biotinylated antigen-antibody complex on the surface of the wells. Finally, HRP enzyme activity is determined by 3,3’,5,5’-Tetramethylbenzidine (TMB) and the concentration of mouse/rat PYY is calculated.