预期应用
ELISA法定量测定人血清、血浆或其它相关液体中肾素(Renin)含量。
实验原理
肾素是一种蛋白水解酶，经肾静脉进入血液。能催化血浆中的血管紧张素原（在α2球蛋白中）转变成血管紧张素Ⅰ（ANG I），血液和肺组织中的转换酶（ACE）使血管紧张素Ⅰ降解为血管紧张素Ⅱ（ANG II），后者可被氨基肽酶水解为血管紧张素Ⅲ（ANG III）。
本试剂盒应用双抗体夹心酶标免疫分析法测定标本中肾素水平。用纯化的抗体包被微孔板，制成固相抗体，往包被单抗的微孔中依次加入肾素抗原、生物素化的抗人肾素抗体、HRP标记的亲和素，经过彻底洗涤后用底物TMB显色。TMB在过氧化物酶的催化下转化成蓝色，并在酸的作用下转化成最终的黄色。颜色的深浅和样品中的肾素呈正相关。用酶标仪在450nm波长下测定吸光度（OD值），计算样品浓度。
Intended use
This immunoassay kit allows for the specific measurement of Human Renin concentrations in cell culture supernates, serum and plasma.
Introduction
Renin is a member of the aspartyl proteinase family produced largely in part by the juxtaglomerular cells in the kidney.Renin differs from the other members of this class by having a pH optimum near neutral pH region with native substrates instead of 2.0 to 3.4 This more neutral pH optimum allows it to be functional in the plasma. Renin also has very high selectivity for substrate due to quite long peptide recognition on either side of the peptide bond undergoing cleavage. An octapeptide substrate was the minimum length to be cleaved by renin. Renin plays a crucial role in the regulation of blood pressure and salt balance through the cleavage of angiotensinogen, which is the only known physiological substrate of renin. Renin releases the decapeptide angiotensin I, which in turn is further converted to vasoactive hormone angiotensin II by angiotensin converting enzyme (ACE). Renin is produced as prorenin with 43 pro residues at the N-terminal of mature renin. The inactive prorenin becomes activated proteolytically by trypsin, cathepsin B, or other proteinases.
Test principle
This assay employs the quantitative sandwich enzyme immunoassay technique. A monoclonal antibody specific for Renin has been pre-coated onto a microplate. Standards and samples are pipetted into the wells and any Renin present is bound by the immobilized antibody. An enzyme-linked polyclonal antibody specific for Renin is added to the wells. Following a wash to remove any unbound antibody-enzyme reagent, a substrate solution is added to the wells and color develops in proportion to the amount of Renin bound in the initial step. The color development is stopped and the intensity of the color is measured. | 
