Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: EC:3.4.21.4 (trypsin)
42,187 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Kininogens are the major mammalian plasma cysteine proteinase inhibitors; a kininogen-like protein was also found in the snake Bothrops jararaca plasma. This communication describes a kininogen-like protein in plasma of Caiman crocodilus vacare. Caiman crude plasma, unlike snake plasma, contains a detectable cysteine proteinase inhibitor. The inhibitor was purified by DEAE-Sephadex ion-exchange chromatography and chromatography on carboxy-methylated-papain-Sepharose. The estimated molecular weight of Caiman cysteine proteinase inhibitor is 70,000. Caiman plasma also hydrolyzes plasma kallikrein synthetic substrates and inhibits trypsin. Reptilian kininogen may lack the site for interaction with plasma prokallikrein, and the sequence of the released kinin may be distinct from bradykinin. The poor effectiveness of bradykinin on reptile smooth muscle shows that the reptile kinin receptors may be adapted to a specific kinin.
...
PMID:Caiman kininogen-like cysteine proteinase inhibitor. 146 83

The distribution in the nervous system of T-kininogen, the third kallikrein-resistant kininogen of the rat, was determined using bioassays and a radioimmunoassay system. In rat brain homogenates, trypsin released large amounts of a kinin-like myostimulating activity while urinary kallikrein released small amounts. The kinins released by trypsin were identified by HPLC as mostly T-kinin. Radioimmunoassays showed that a T-kininogen-like immunoreactive factor was uniformly distributed throughout the central nervous system. Higher levels were found in female rats than in male rats. Maximum levels were observed in newborn animals. A slight increase of T-kininogen content of the brain was observed after turpentine injection while T-kininogen level in liver was dramatically increased. T-kininogen plasma contamination to the nervous tissues was estimated by injecting 125I-labelled T-kininogen. The T-kininogen content of rat cultured cells and neurons was also examined. Highest levels were found in dorsal root ganglia neurons, lower levels in Schwann cells, phaeochromocytoma cells, mixed cells from spinal ganglion and in astrocytes. Immunocytochemistry showed the presence of T-kininogen in the cytoplasm of cultured dorsal root ganglia neurons and embryonic hippocampal neurons. The distribution of T-kininogen throughout the central and peripheral nervous system of the rat, the variations of its level during the life span suggest that T-kininogen would play the role of a cysteine proteinase inhibitor and not that of a T-kinin-releasing substrate in nervous tissues.
...
PMID:Distribution of immunoreactive T-kininogen in rat nervous tissues. 161 79

Activities of cysteine and trypsin-like proteinase inhibitors and of cathepsin D were measured in mixed saliva of periodontitis patients with conditions of varying severity. Salivary proteinase inhibitor activities were found related, to a certain measure, to the severity of inflammation. Salivary antitryptic activity was somewhat reduced and cysteine proteinase inhibitor activity elevated in patients with non-severe periodontitis. In cases with medium-severe and severe periodontitis salivary proteinase activity was augmenting, approaching the normal value, whereas cysteine proteinase inhibitor level was significantly decreased. A reduction of salivary inhibitor activity was related to the formation of inhibitor-proteinase complexes, whereas a rise of this activity was explained by release of inhibitors from these complexes resulting from dissociation. This is possibly due to the formation of partially cleaved inhibitor form because of cathepsin effects.
...
PMID:[The proteinase inhibitors of mixed saliva in periodontitis]. 185 78

Three types of cloned cDNA sequences for rat low molecular weight prekininogens were isolated and determined by molecular cloning and sequence analysis. The deduced amino acid sequences indicated that one, termed K-prekininogen, represents the counterpart of the known low molecular weight prekininogen present in other mammals, while the other two, called T-prekininogens, contain a novel T-kinin sequence which was recently identified from rat plasma. Although T- and K-prekininogens are highly homologous with each other, both of the T-prekininogens contain methionine, instead of arginine or lysine, as an amino acid preceding T-kinin and exhibit two consecutive amino acid deletions in the preceding region of T-kinin as compared with K-prekininogen. The former finding accounts for the previous observation of strong resistance of T-kininogens to cleavage with trypsin or kallikreins, while the latter finding has been explained by the structural analysis of genomic clones in which T-kinin-coding exon is contracted at its intron junction. A partial nucleotide sequence reported recently for the rat major acute phase protein (alpha 1-MAP) mRNA was found to be extremely related to the corresponding portion of the rat T-prekininogen mRNA. Furthermore, consistent with the previous report of the structural identity of major acute phase protein and alpha 1-cysteine proteinase inhibitor, kininogen closely resembles not only the former but also the latter in the amino acid compositions. The interrelationship among the triad of these proteins has been discussed.
...
PMID:Primary structures of the mRNAs encoding the rat precursors for bradykinin and T-kinin. Structural relationship of kininogens with major acute phase protein and alpha 1-cysteine proteinase inhibitor. 241 18

We examined whether Brown Norway rat plasma (BN/May Pfd f) contains alpha 1-cysteine proteinase inhibitor (alpha 1-CPI), also called major acute phase alpha 1-protein or T-kininogen. T-kininogen is a low molecular weight kininogen from which kinin can be released by trypsin but not by kallikreins. The BN plasma reacted with rabbit anti-alpha 1-CPI gamma globulins. Purified alpha 1-CPI released a kinin-like activity with trypsin and with homogenate of salivary glands, as Brown Norway rat plasma did. High concentration of added rat urine induced a small release (10%) of kinin from alpha 1-CPI. Preincubation of Brown Norway rat plasma with rabbit anti-rat alpha 1-CPI gamma-globulins nearly suppressed the kinin-forming substrate of trypsin in this plasma. These results indicated that plasma of our Brown Norway rats contains only alpha 1-CPI as kinin-forming substrate. This plasma contains low amount of alpha 2-macroglobulin, while its content in orosomucoid and haptoglobin was a little larger than that of Wistar rat plasma.
...
PMID:Acute phase plasma proteins in kininogen-deficient Brown Norway rats. 243 May 37

The skeletal muscle content of three rat proteinase inhibitors, a 1-proteinase inhibitor, contrapsin and a 1-cysteine proteinase inhibitor was measured by immunochemical techniques following streptozotocin-induced diabetes. When compared with normal rats, a 1-cysteine proteinase inhibitor and a 1-proteinase inhibitor levels remained essentially unchanged, whereas the content of rat contrapsin was reduced by nearly 80% after the onset of diabetes. Similarly, fasting of rats for three days resulted in a lowering of the levels of contrapsin in skeletal muscles. Under these conditions, levels of chymotrypsin-like activity (chymase) were increased by 150%, whereas the content of the trypsin-like, neutral proteinase was unchanged. Kinetic studies in vitro with Tosyl-Gly-Pro-Arg-4-nitroanilide as substrate showed no inhibition of the trypsin-like proteinase by a 1-proteinase inhibitor, while contrapsin inhibited the enzyme with a Ki value of 40nM. The changing pattern of these proteinases and their potential inhibitors (chymase/a 1-proteinase inhibitor and trypsin-like proteinase/contrapsin) may be a factor contributing to muscle wasting as observed in diabetes and fasting.
...
PMID:Changes in proteinase/proteinase inhibitor levels in rat skeletal muscle tissue during diabetes and fasting. 306 Jan 41

Conditions for extraction of rat brain soluble and particulate cysteine proteinase inhibitors (CPIs) were compared and an optimal one was selected to isolate low- and high-molecular-weight forms active toward papain or brain cathepsins B/L. The different forms were purified by affinity chromatography on alkylated papain, and identified on sodium dodecyl sulfate-polyacrylamide gel electrophoresis gels by use of Schiff's reagent, or by immunoblots using antisera to monomer or polymeric forms of human urinary cystatin c, to a human plasma histidine-rich glycoprotein (HRG), or to rat plasma T-kininogen. In particulates containing nuclei (P1) or synaptosomes (P2) the predominant CPI was an 80-kDa glycoprotein cross-reacting to anti-HRG and shown to be a T-kininogen by treatment with TPCK-trypsin, and subsequent bioassay of the released kinins. The levels found in rat brain were approximately 0.5 nmol/g wet weight. The higher-molecular-weight CPI potently inhibited cathepsin L hydrolysis of Leu-enkephalin at the Gly2-Gly3 bond with a Ki 10(-10) M. In contrast the low-molecular-weight CPIs were present in postmicrosomal fractions (S3) and cross-reacted with anti-cystatin c, but not with anti-HRG, anti-lysozyme, anti-beta protein amyloid peptide, or anti-T-kininogen. The low-molecular-weight forms were present at approximately 1-1.5 nmol/g wet weight and resembled "cerebrocystatin" purified previously from rat brain cytosol by M. Kopitar, F. Stern, and N. Marks [1983) Biochem. Biophys. Res. Commun. 112, 1000-1006.).
...
PMID:Diversity of rat brain cysteine proteinase inhibitors: isolation of low-molecular-weight cystatins and a higher-molecular weight T-kininogen-like glycoprotein. 326 47

A direct radioimmunoassay (RIA) for rat high molecular weight kininogen (HMW Kg) was developed that enabled us to detect 71 fmol/ml of HMW Kg. The antibodies did not crossreact in the RIA with up to 5 nmol of purified rat alpha 1 cysteine proteinase inhibitor (T-kininogen). When various quantities of pure HMW Kg were either quantified by the RIA or by the measurement of kinin contents determined after trypsin hydrolysis, identical values were obtained by both methods. This RIA allowed the measurement of HMW Kg in 0.015 to 1 microliter of rat plasma. HMW Kg levels in plasma of Wistar rats and in Brown Norway rats of the Orlean Strain (BN/Orl) were 1.52 +/- 0.05 (n = 6) and 2.050 +/- 0.015 (n = 8) nmol/ml respectively. In the Brown Norway rats of the Katholiek strain (BN/Kat) that are considered to be deficient in HMW Kg, immunoreactive HMW Kg levels were less than 2% of those of the BN/Orl rats. These results confirm that the BN/Kat animals have a molecular defect in HMW Kg.
...
PMID:Direct radioimmunoassay for rat high molecular weight kininogen. Measurement of immunoreactive high molecular weight kininogen in normal and kininogen deficient plasma. 348 Dec 12

The effect of vitamin E deficiency on levels of proteinase inhibitors in sex glands of male rats was studied. Inhibitor levels against cysteine proteinases, such as ficin and cathepsin H, and against serine proteinase such as trypsin were examined. Vitamin E deficiency for 4 mo after weaning induced a fivefold increase in cysteine proteinase inhibitor level in testis, a two- to fourfold increase in prostate and epididymis and no change in seminal vesicle. No appreciable change was observed in trypsin inhibitor level in testis, epididymis or seminal vesicle. Therefore, vitamin E deficiency was reflected most sensitively by the cysteine proteinase inhibitor level in testis. These observations agree with our previous findings that alpha-cysteine proteinase inhibitors in serum increased greatly whereas trypsin inhibitor in serum did not change in vitamin E-deficient rats. Major histological changes were observed in the testes of rats fed a vitamin E-deficient diet for 4 mo, although testis weight was not significantly affected by vitamin E deficiency.
...
PMID:Enhancement of testicular cysteine proteinase inhibitor level in vitamin E-deficient rats. 349 20

The fluorescent proteinase transition-state analog inhibitor, dansyl-L-argininal (DnsArgH), may be a selective probe of cysteine and serine-type proteinases in a fibrosarcoma tumor cell line (HSDM1C1). DnsArgH binds with high affinity to proteinases because of its transition-state analog properties, and on association it gives a dramatically increased fluorescent yield. The DnsArgH binding is inhibited by the serine proteinase inhibitor diisopropyl fluorophosphate and by the cysteine proteinase inhibitor p-chloromercuribenzoate. The fluorescence emission appears at its maximum steady-state yield immediately on addition of DnsArgH to the HSDM1C1 fibrosarcoma cells. The immediacy of the DnsArgH reaction supports the contention that DnsArgH binding may be to cell surface-associated proteinases. Quantification of the cell proteinase concentration, by comparison of the fluorescence yield obtained from DnsArgH interactions with bovine trypsin and papain, indicates 10(-15) to 10(-16) mol of proteinase per HSDM1C1 cell. In fluorescence microscopy, DnsArgH fluorescence appears distributed throughout the fibrosarcoma cell without association to organelles. DnsArgH fluorescence from normal fibroblast controls (IMR-90) was found to be substantially lower than in the transformed fibrosarcoma cells, supporting a hypothesis that proteinases have a role in malignancy.
...
PMID:Tumor cell proteinase visualization and quantification using a fluorescent transition-state analog probe. 636 97


1 2 3 Next >>