Description
Principle of the assay: This assay employs a two-site sandwich ELISA to quantitative PTH in Rat serum, plasma. An antibody specific for PTH has been pre-coated onto a microplate. Standards and samples are pipetted into the wells and any PTH present is bound by the immobilized antibody. After removing any unbound substances, a biotin - conjugated antibody specific for PTH is added to the wells. After washing, Streptavidin conjugated Horseradish Peroxidase (HRP) is added to the wells. Following a wash to remove any unbound avidin-enzyme reagent, a substrate solution is added to the wells and color develops in proportion to the amount of PTH bound in the initial step. The color development is stopped and the intensity of the color is measured.
Background: Parathyroid hormone is secreted by the parathyroid glands as a polypeptide containing 84 amino acids. It acts to increase the concentration of calcium (Ca2+) in the blood, whereas calcitonin (a hormone produced by the parafollicular cells (C cells) of the thyroid gland) acts to decrease calcium concentration. PTH acts to increase the concentration of calcium in the blood by acting upon parathyroid hormone receptor in three parts of the body: PTH half-life is approximately 4 minutes. It has a molecular mass of 9.4 kDa. PTH was one of the first hormones to be shown to use the G-protein, adenylyl cyclase second messenger system.Normal total plasma calcium level ranges from 8.5 to 10.2 mg/dL (2.12 mmol/L to 2.55 mmol/L)