Description
Principle of the assay: This assay employs a two-site sandwich ELISA to quantitative GHRL in Chicken serum, plasma. An antibody specific for GHRL has been pre-coated onto a microplate. Standards and samples are pipetted into the wells and any GHRL present is bound by the immobilized antibody. After removing any unbound substances, a biotin - conjugated antibody specific for GHRL 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 GHRL bound in the initial step. The color development is stopped and the intensity of the color is measured.
Background: Ghrelin (pr. GREL-in), the "hunger hormone", is a peptide produced by ghrelin cells in the gastrointestinal tract which functions as a neuropeptide in the central nervous system. Beyond regulating hunger, ghrelin also plays a significant role in regulating the distribution and rate of use of energy. When the stomach is empty, ghrelin is secreted. When the stomach is stretched, secretion stops. It acts on hypothalamic brain cells both to increase hunger, and to increase gastric acid secretion and gastrointestinal motility to prepare the body for food intake. The receptor for ghrelin is found on the same cells in the brain as the receptor for leptin, the satiety hormone that has opposite effects from ghrelin. Ghrelin also plays an important role in regulating reward perception in dopamine neurons that link the ventral tegmental area to the nucleus accumbens (a site that plays a role in processing sexual desire, reward, and reinforcement, and in developing addictions) through its colocalized receptors and interaction with dopamine and acetylcholine. Ghrelin is encoded by the GHRL gene and is presumably produced from the cleavage of the prepropeptide ghrelin/obestatin. Full-length preproghrelin is homologous to promotilin and both are members of the motilin family