Components of plasma and tissue kallikrein-kinin system in the urine of patients with latent, nephrotic and hypertonic forms of glomerulonephritis.

Activities of main components of KKS were estimated in the urine of patients with latent, nephrotic and hypertonic forms of chronic glomerulonephritis (ChGN) and compared to those parameters in urine of healthy persons. The data obtained allow to make a conclusion concerning the pathogenetic and the compensatory role of plasma KKS in the nephrotic form of ChGN.

Kinetics of Lys-bradykinin release by porcine pancreatic kallikrein from rabbit low molecular weight kininogen.

The initial rates of Lys-bradykinin release by porcine pancreatic kallikrein from rabbit low molecular weight kininogen are found to follow the Michaelis-Menten kinetics with kc = 0.62 sec-1 and Km = 1.93 microM at substrate concentrations 0.3-1.3 microM, but at higher ones the Michaelis dependence is broken. Inhibition of the reaction by its product(s) with Kp < Km is revealed with integral analysis methods in a range of 4.5-270 microM kininogen.

[Components of kallikrein-kinin system in the urine of patients with glomerulonephritis]. / Komponenty kallikrein-kininovoi sistemy v moche bol'nykh glomerulonefritom.

Activities of main components of the kallikrein-kinin system: tissue (renal) and blood plasma kallikreins, kininases I and II, bradykinin-activating activity as well as free kinins, were estimated in urine of patients with latent and nephrotic forms of glomerulonephritis as compared with those parameters in urine of healthy persons. Content of tissue kallikrein was decreased in urine of patients with nephrotic form of glomerulonephritis as distinct from the disease latent form and healthy persons. At the same time, urine of these patients with nephrotic form contained elevated amount of blood plasma kallikrein and other proteinases of blood plasma origin. Bradykinin-inactivating activity as well as activities of kininase I and II were increased in urine of patients with the disease latent form 2-, 7- and 2.5-fold, respectively, and in urine of patients with nephrotic form--40-, 45- and 40-fold, respectively as compared with normal state. Daily excretion of free kinins with urine of healthy persons constituted 6.6 +/- 0.9 micrograms-eqv of bradykinin (BK), in patients with latent and nephrotic forms of glomerulonephritis--1.7 +/- 0.3 and 2.8 +/- microgram-eqv BK, respectively. Three kinins were found in all the examined persons when urine was collected in acid medium: BK, lysyl-BK and Met-Lys-BK; content of BK was minimal in urine of healthy persons and maximal--in urine of patients with nephrotic form of the disease. Clinical importance of the patterns studied and their role in correction of treatment course of patients with nephrotic form of glomerulonephritis are discussed.

[Single-chain, low molecular weight kininogen in the blood plasma of rabbits: isolation and fragmentation by porcine pancreatic kallikrein]. / Odnotsepochechnyi nizkomolekuliarnyi kininogen plazmy krovi krolika: vydelenie i kharakter fragmentatsii pankreaticheskim kallikreinom svin'i.

A highly purified preparation of low molecular weight kininogen (LMrK) was isolated from the plasminogen-free rabbit blood plasma, using chromatography on DEAE-Sepharose CL-6B, gel filtration on Ultrogel AcA 34 and Sephadex G-100 as well as gradient chromatography on a hydroxylapatite column. The yield of the 320-fold purified LMrK was 16%. Trypsin released 13-14 micrograms-eq. of bradykinin (BK) from 1 mg of LMrK or 0.85-0,95 mol of BK per mol of kininogen. Rabbit LMrK consists of one polypeptide chain of Mr 69 000 and pI 4.63. Porcine pancreatic kallikrein splits off kinin from the LMrK polypeptide chain by disrupting two peptide bonds resulting in the formation of S-S-bound two chain molecule. After reduction of the S-S bonds by dithioerithritol the latter is separated into a heavy (Mr 61 000) and light (Mr 6 800) chains. A biologically active peptide was isolated from the products of CNBr cleavage of LMrK. This peptide consists of Lys-BK elongated from the C-terminal with several amino acid residues. Rabbit LMrK closely resembles human LMrK in terms of Mr, pI and location of the kinin fragment in the protein molecule.

High concentrations of free kinins and kinin system components in abdominal transudate of a patient with nephrotic syndrome.

High levels of bradykinin (60--80 ng/ml) were found in abdominal transudate from a patient with nephrotic syndrome caused by chronic glomerulonephritis. The abdominal transudate contained neutral kininogenase and its precursor, identified with plasma kallikrein and prekallikrein, respectively, as well as both forms of kininogen, the low-molecular-weight form predominating. The abdominal transudate was characterized also by very low kininase activity and low levels of alpha 1-antitrypsin (0.46 g/l) and alpha 2-macroglobulin. Large amounts of very low density lipoproteins were present in the transudate. Despite the difference in total protein content between the abdominal transudate and the patient's serum (4.3 g/l and 48 g/l, respectively) their protein fraction composition was similar. The data obtained suggest that bradykinin is important in maintenance of long-lasting blood vessel hyperpermeability, which, in turn, is a driving force in the pathogenesis of refractory nephrotic edema.

[Identification of kinins releasing by pig pancreatic kallikrein from rabbit low molecular weight kininogen]. / Identifikatsiia kininov, osvobozhdaemykh pankreaticheskim kallikreinom svin'i iz nizkomolekuliarnogo kininogena krolika.

Pig pancreatic kallikrein is found to release kinins from LMrK with the rate of 800 mkg. eq. of bradykinin per min, per 1 mg of the enzyme. This kininogenase reaction is not accompanied by a ddep fragmentation of the kininogen molecule, because only a high molecular weight fragment which Mr is practically equal to that of intact LMrK (55-60 000), and a peptide identified as bradykinin, are found in hydrolysate. In the same conditions human salivary kallikrein is found to form kallidin from LMrK.