产品描述:Factor XII or Hageman factor (EC 3.4.21.38), is the zymogen form of factor XIIa, a serine protease involved in Coagulation Pathway. This single chain zymogen is activated by Kallikrein into a two-chain serine protease (XIIa) with a heavy chain (factor XIIa-alpha) and a light chain. Human Factor XII and Prekallikrein are thought to be involved in a reciprocal activation mechanism in which Factor XIIa activates Prekallikrein to Kallikrein, which in turn converts Factor XII to XIIa. Factor XIIa activates Factor XI to XIa thereby triggering the Contact Factor cascade. The defects in this gene do not cause any clinical symptoms but prolong the whole blood clotting time. BioVision's Factor XIIa activity assay kit utilizes the ability of factor XIIa to cleave a synthetic substrate to release p-Nitroaniline (pNA) which can be quantitatively measured by a colorimetric assay (OD405 nm). The kit is easy-to-use and can detect Factor XIIa (as low as 1 mPEU) from plasma sampless.