The kinins are pharmacologically active polypeptides, which are released in the tissues and body fluids as a result if the enzymatic action of kallikreins on kininogens. The kinin family includes BK (Arg-ProPro-gly-Phe-Ser-Pro-Phe-Arg), kallidin (Lys- -Arg-Pro-Pro-Gly-PheSer-Pro-Phe-Arg) and methionyl-lysyl-BK (Met-Lys-Arg-Pro-ProGly-Phe-Arg). Kallidin and methionyl-lysyl-BK are converted into BK by aminopeptidases present in plasma and urine [1]. Kinins are rapidly (<15 sec) inactivated by circulating kininases [2]. Kininogens are multifunctional proteins derived mainly from alpha – 2 globulin. In humans, the two forms of kininogens are; High Molecular Weight Kininogen (HMWK) and Low Molecular Weight Kininogen (LMWK) [3]. These kininogens vary from each others in molecular weight, susceptibility to plasma and tissue kallikreins and in their physiological properties [4]. They are synthesized in the liver and circulate in the plasma and other body fluids. In addition, there is a T-kininogen in the rat plasma, which is considered to be an acute phase reactant of inflammation [5]. This kininogen releases T-kinin by the enzymatic action of T- kallikrein in rats [6]. Tissue kallikrein is found in various organs such as the kidney, heart and synovial tissue [7,8]. These kallikreins differ from one another in molecular weight, biological function, physicochemical and immunological properties.