Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts: Gene/Protein Disease Symptom Drug Enzyme Compound   Target Concepts: Gene/Protein Disease Symptom Drug Enzyme Compound

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Query: EC:3.4.21.4 (trypsin)
42,187 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The consumption of kininogen (measured as kinin-releasable material) was studied in an experimental model in vitro. Analyses were made following the addition of increasing amounts of human cationic trypsin to human serum and plasma. The consumption of kininogen was correlated with the degree of saturation of the plasma proteinase inhibitors alpha 2-macroglobulin (alpha 2-M) and alpha 1-proteinase inhibitor (alpha 1-PI) with trypsin in the presence and absence of aprotinin (Trasylol). The level of kininogen fell dramatically when alpha 2-M was saturated to 70% in spite of 90% free alpha 1-PI. Trypsin-alpha 2-M complexes had no effect on kininogen levels. 60 mumol/l of aprotinin, i.e. approximately 3 X 10(6) KIU/l, blocked only 60% of the trypsin-induced kininogen consumption in serum, while 15 mumol/l of aprotinin blocked 100% of this consumption in plasma. With increasing concentration of aprotinin in serum, a decreasing consumption of alpha 2-M and especially of alpha 1-PI was observed on the addition of trypsin. The high aprotinin concentration needed to block trypsin-induced kininogen cleavage in human serum or plasma may explain the poor clinical effect of aprotinin to date in human acute pancreatitis.
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PMID:Influence of plasma proteinase inhibitors and aprotinin on trypsin-induced bradykinin release in vitro in man. 619 66

The protective role of alpha 2-macroglobulin, alpha 1-antitrypsin and Aprotinin against trypsin-induced effects on C3 and kininogen was studied in a human in vitro model. When human cationic trypsin was added to human serum or plasma, there was a gradual saturation of alpha 2-macroglobulin and later of alpha 1-antitrypsin. When alpha 2-macroglobulin was 70% saturated, there was a prompt cleavage of both C3 and kininogen, in spite of 80% free and active alpha 1-antitrypsin. These biochemical changes and antiprotease levels are identical to our findings in patients with acute pancreatitis, especially in their peritoneal exudate. Very high concentrations of Aprotinin, 5-15 times higher than ever used clinically, blocked the cleavage of both C3 and kininogen, while doses commonly used clinically were without significant effect. The clinical implications are: A trypsin-induced activation of both the complement and kinin system with clinical consequence is possible in patients with acute pancreatitis because of very low alpha 2-macroglobulin levels. Aprotinin in adequate doses, 5-15 times higher than ever used clinically, seems to protect against activation of two systems.
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PMID:On the potential role of trypsin and trypsin inhibitors in acute pancreatitis. 620 Oct 50

We examined the effects of acute hemorrhagic pancreatitis in the sheep lung lymph fistula preparation. Pulmonary lymph flow and transvascular protein clearance increased after pancreatitis was induced by injection of sodium taurocholate and trypsin into the pancreas in control sheep. However, neither parameter was altered in sheep pretreated with the protease inhibitor, Trasylol (initial bolus injection, 5,000 KIU/kg followed by 5,000 KIU/kg for 4 h). In addition, in the control animals, both peripheral granulocyte count and the arterial fibrinogen concentration decreased, but these changes did not occur after pancreatitis in the Trasylol-pretreated animals, suggesting that the generation of proteases is responsible for granulocyte sequestration and intravascular coagulation after pancreatitis. The platelet count decreased comparably in both groups, indicating a lack of involvement of platelets in lung vascular injury. Therefore, generation of proteases is an important factor in the mediation of increased lung vascular permeability after acute hemorrhagic pancreatitis.
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PMID:Pancreatitis-induced increase in lung vascular permeability. Protective effect of Trasylol. 620 Oct 93

The integrity of the VP1 protein of foot-and-mouth disease virus was assessed by polyacrylamide gel electrophoresis (following storage at 4 degrees C of conventional tissue culture preparations and concentrated preparations of the virus. There was little evidence of VP1 degradation in tissue culture filtrates whereas considerable degradation was observed throughout a range of different concentrates. The use of the proteolytic enzyme inhibitor 'Trasylol' appeared to inhibit VP1 degradation in some virus preparations. Vaccination experiments with guinea pigs indicate that cleavage of O BFS 1860 virus by a range of proteolytic enzymes was always associated with a lowered stimulation of neutralising antibody and total antibody. Experiments with six other strains treated with trypsin gave similar results to those obtained with O BFS 1860.
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PMID:Observations and implications of proteolysis in preparations of foot-and-mouth disease virus. 628 Nov 9

The rate of degradation of cholecystokinin octapeptide, related fragments and analogs by human and rat plasma was investigated, using high pressure liquid chromatography for the separation and identification of the degradation products. CCK tetrapeptide showed a half-life of 13 min in human plasma while its cleavage in rat plasma occurred at a very high rate (half-life of less than 1 min). The kinetics of disappearance of both sulphated and unsulphated CCK-8 indicated more than a single rate of degradation; the faster degrading system showed a half-life of 18 min for unsulphated CCK-8 and of 50 min for the sulphated peptide in human plasma as compared respectively with 5 and 17 min in rat plasma. The cleavage of CCK-8 was inhibited by bestatin and puromycin, suggesting that aminopeptidases play a major role in the breakdown of this peptide. CCK-9 analogs were rapidly converted into their corresponding octapeptides (half-life of 2.7 min in human plasma). This conversion was inhibited by puromycin and bestatin, suggesting the participation of aminopeptidase(s) probably specific for basic amino acids. CCK decapeptide exhibited a greater stability than the nonapeptides (half-life of 30 and 45 min in human and rat plasma respectively) and also gave rise to CCK-8 as degradation product. This cleavage was not affected by aminopeptidase inhibitors but was decreased by aprotinin (Trasylol), suggesting that trypsin-like and/or kallikrein-like enzyme(s) were involved in the plasma metabolism of this peptide.
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PMID:Degradation of cholecystokinin octapeptide, related fragments and analogs by human and rat plasma in vitro. 629 Oct 99

A type IV collagen-degrading enzyme activity secreted by a highly metastatic mouse tumor was purified by concanavalin A- and type IV collagen-agarose affinity chromatographies followed by gel filtration on Bio-Gel A-0.5 m. The apparent molecular weight of the enzyme was 160,000 but about 70,000 when Triton X-100 was added to the column buffer. The purified enzyme protein was resolved on sodium dodecyl sulfate-polyacrylamide gel electrophoresis into two polypeptide chains of about 68,000 and 62,000 daltons. The enzyme activity could be increased by preincubation with trypsin and it is possible that the two chains represent latent and active enzyme forms. The enzyme activity was not reduced in the presence of dithiothreitol, it had a pH optimum of 7.6 and was inhibited by EDTA but not N-ethylmaleimide, phenylmethylsulfonyl fluoride, or Trasylol. The inhibition with EDTA was reversible. The pro-alpha 1(IV) and pro-alpha 2(IV) chains of the type IV procollagen substrate were both degraded at a similar rate to form two pairs of degradation fragments corresponding in molecular weights to about 70 and 30% of the original size chains. The presence of Triton X-100 increased slightly the activity of the enzyme and diminished the reduction of its activity upon freezing, indicating that the enzyme is a hydrophobic protein.
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PMID:Purification and characterization of a murine basement membrane collagen-degrading enzyme secreted by metastatic tumor cells. 629 20

Proteolytic enzyme activity was detected in a large number of concentrated preparations of inactivated foot-and-mouth disease virus. Several lines of evidence indicated that at least some of this activity could be attributed to BHK cells, although low levels of microbial contamination in many of our preparations could not be discounted and would certainly enhance the cellular proteolytic activity. From an experiment with different concentrations of trypsin, it was concluded that the proteolytic activities of virus concentrates were sufficient to cause significant degradation of VP1. It was also shown that Trasylol and ox serum were effective inhibitors of proteolytic enzymes in concentrated virus preparations stored at 4 degrees C for 8 months.
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PMID:The detection and inhibition of proteolytic enzyme activity in concentrated preparations of inactivated foot-and-mouth disease virus. 630 Jan 29

Extracts of both infiltrating ductal carcinoma and non-tumorous tissue were obtained from the same mastectomy specimen of a lactating female patient. The extracts were ultrafiltered and concentrated to recover proteins having nominal molecular weights between 1000 and 50,000 daltons. Although the final concentrates of both samples contained proteinase-inhibitory activities with electrophoretic mobilities similar to that of Trasylol, only the extract from the tumour had significant trypsin-inhibitory activity as expressed by the inhibition of the hydrolysis of TAME (p-tosyl-L-arginine methyl ester). Molecular sieve chromatography by high performance liquid chromatography of the final concentrate of the tumour indicated that the activity was present in three peaks having apparent molecular weights of less than 17,000.
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PMID:Low molecular weight proteinase inhibitors. II. Extraction and identification of activity from infiltrating ductal carcinoma during lactation. 631 92

Plasma prekallikrein, a precursor protein of kallikrein [EC 3.4.21.8], was highly purified from porcine plasma by chromatography on a DEAE-Sephadex A-50 column, followed by rechromatography on a DEAE-Sephadex A-50 column, chromatography on a CM-Sephadex C-50 column and affinity chromatography on a p-aminobenzamidine-epsilon-aminocaproic acid-Sepharose 4B column. By this procedure, 3.3 mg of purified material was obtained from 1.6 liters of porcine plasma and about 240-fold purification was achieved from the first DEAE-Sephadex A-50 chromatography. The purified protein was found to give a single band on sodium dodecyl sulfate (SDS)-polyacrylamide gel disc electrophoresis. This preparation did not contain kallikrein, Factor XII (Hageman factor) of the blood coagulation system, high molecular weight (HMW) kininogen or plasma kininase. Thus, the material is presumed to be functionally pure. The molecular weight of prekallikrein was estimated to be about 88,000 by SDS-polyacrylamide gel electrophoresis, and prekallikrein consists of a single polypeptide chain. Activation of prekallikrein by trypsin [EC 3.4.21.4] was found to involve the cleavage of a single peptide bond on the disulfide-bridged polypeptide chain, and no change of molecular weight was observed during the activation. This trypsin-activated kallikrein released kinin rapidly from bovine HMW kininogen. However, liberation of kinin was extremely slow from bovine low molecular weight (LMW) kininogen. The kallikrein activity was inhibited by soybean trypsin inhibitor (SBTI) and Trasylol, but not by Polybrene or egg-white trypsin inhibitor (EWTI).
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PMID:Purification of prekallikrein from porcine plasma and its conversion to active kallikrein. 655 87

Line 10 guinea pig carcinoma cells cultured in serum-free medium for 4 hr elaborate plasminogen activator (PA) activity that remained in the supernatant after ultracentrifugation (100,000 X g, 90 min). PA activity in line 10 conditioned medium occurred in both active and cryptic forms. The vast majority of active PA adsorbed to lysine-Sepharose and could be eluted at low pH as several activities that electrophoresed in the Mr 50,000 to 80,000 range on nonreduced sodium dodecyl sulfate-polyacrylamide gel electrophoresis. A small amount of active PA, running in the Mr 50,000 to 60,000 region, and cryptic PA did not adhere to lysine-Sepharose. Treatment of lysine-Sepharose-nonadherent fractions with catalytic amounts of plasmin or trypsin induced substantial new PA activity that adsorbed to lysine-Sepharose, bound [3H]diisopropylfluorophosphate, and that electrophoresed as several bands of activity with molecular weights from 50,000 to greater than 100,000 on sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Of additional interest, the amount of active PA measured in conditioned medium was substantially increased when certain protease inhibitors, tranexamic acid, epsilon-aminocaproic acid, or Trasylol, were included during culture.
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PMID:Cryptic and active plasminogen activators secreted by line 10 tumor cells in culture. 668 8


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