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 biochemical properties of renin, extracted from human pituitary specimens obtained at autopsy, were studied using a specific antirenin antibody raised against human kidney renin. The following results were obtained. The molecular weight of pituitary renin was estimated to be about 37,000 daltons by gel filtration through Sephadex G-100. The optimum pH of pituitary renin was between 6.0 approximately 7.0, while that of a renin-like substance which did not react with the antirenin antibody had an acidic pH of 4.0, with a pH comparable to that of the cathepsin D-like enzyme in the pituitary tissue. The presence of two different isoelectric-point species of pituitary renin was revealed by isoelectric focusing, one with a point of pH 4.47 and the other with that of pH 5.77. The Km value of pituitary renin was 37.9 microM for synthetic human renin substrate. Affinity chromatography of the pituitary renin on a Concanavalin-Sepharose column showed that most (87.4%) of the pituitary renin did not contain glycoprotein residues. Treatment with either trypsin or glandular kallikrein increased the renin activity, indicating the presence of an inactive form of renin in the pituitary tissue. From these findings, it is concluded that specific renin exists in human pituitary tissue. It seems likely that the pituitary renin is of local origin rather than contamination of the circulating enzyme.
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PMID:[Biochemical properties of renin in human pituitary tissue]. 389 64

Inactive renin in the brain of spontaneously hypertensive rat was investigated. The results are as follows. Treatment with either trypsin or glandular kallikrein of the brain tissue extract caused a rapid and apparent increase in the renin activity at either 0 or 27 degrees C. The molecular weight of the active renin was estimated to be 41,000 or 50,000 daltons, while that of the trypsin-activatable inactive renin was found to be 44,000 or 57,000 daltons on a column chromatography with Sephadex G-100. The contents of the active renin was the highest in the hypothalamus, followed by the striatum, thalamus, midbrain, medulla oblongata, cerebral cortex and cerebellum, while the contents of the trypsin-activatable inactive renin was the highest in the hypothalamus, followed by the striatum, thalamus, cerebellum, midbrain, cerebral cortex and medulla oblongata. These results suggest that inactive renin(s) exist in the brain of spontaneously hypertensive rat. It seems likely that the brain renin-angiotensin system is modulated by the conversion of inactive to active renin(s), which, in turn, plays at least in part a role in the blood pressure regulation through generation of angiotensin II in spontaneously hypertensive rats.
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PMID:[Evidence for the existence of inactive renin in the rat brain. Part II. Distribution of inactive renin in the brain of spontaneously hypertensive rats]. 391 7

Renin-like enzyme(s) in the arterial wall of the spontaneously hypertensive rat (SHR) were activated markedly by either acidic pH or treatment of proteolytic enzymes (trypsin and glandular kallikrein). The highest concentration of renin-like enzyme (active form) was localized in the renal artery (2.51 +/- 0.59 ng angiotensin I generated/mg of protein per h, mean +/- S.D.), followed by the mesenteric (1.58 +/- 0.31), the carotid (1.44 +/- 0.27) and the major aortic trunk (0.20 +/- 0.10), while the highest concentration of the inactive renin-like enzyme was localized in the major aortic trunk (0.97 +/- 0.18), followed by the carotid (0.72 +/- 0.41), the renal (0.71 +/- 0.31) and the mesenteric (0.60 +/- 0.29) arteries. In addition, the active renin-like activity from the mesenteric and the carotid arteries of SHR rats was higher significantly than that of age-matched normotensive Wistar-Kyoto (WKY) rats, despite a similar concentration of total renin-like enzyme of the corresponding arteries of both groups. These results suggest that increased interconversion of the inactive to the active renin-like enzymes in the arterial wall of SHR rats may result in local vasospasm through generation of angiotensin II, which may contribute in part at least to systemic hypertension of SHR rats.
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PMID:Active and inactive renin-like enzymes in the arterial wall of the spontaneously hypertensive rat. 391 27

Rat renal lymph contains 254 +/- 17 ng/ml (means +/- SEM, N = 20) of immunoreactive glandular kallikrein. Like the immunoreactive glandular kallikrein in plasma, it is biologically inactive. Gel filtration of renal lymph reveals profiles for immunoreactive glandular kallikrein, protein, and inhibition of trypsin and kallikrein which resemble those seen for plasma except that high molecular weight plasma components are reduced or missing in renal lymph. In contrast, gel filtration of thoracic lymph reveals immunoreactive glandular kallikrein and protein profiles which are indistinguishable from those seen with plasma. Renin levels are 170-fold higher in renal lymph than in thoracic lymph while angiotensin-converting enzyme levels are only 16% those of thoracic lymph. In keeping with the high renin and low converting enzyme activities, renal lymph contains high levels of angiotensin I. Immunoreactive glandular kallikrein levels in renal lymph, thoracic lymph and plasma do not show the striking differences observed for renin.
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PMID:Kallikrein-kinin and renin-angiotensin systems in rat renal lymph. 608 86

Kallikrein (EC 3.4.21.8) was purified from rat stomach by column chromatography on p-aminobenzamidine-Sepharose, DEAE-Sephadex A-50 and Sephadex G-150 and by isoelectric focusing, measuring its activities to hydrolyse L-prolyl-L-phenylalanyl-L-arginine-4-methyl-coumaryl-7-amide and to release kinin from heat-treated rat plasma. the purified stomach kallikrein showed a single band on polyacrylamide gel electrophoresis at pH 7.0. Its molecular weight was calculated to be 29 000 by gel-filtration on a column of Sephadex G-50. The kallikrein was stable between pH 6-11 and hydrolyzed L-prolyl-L-phenylalanyl-L-arginine-4-methyl-coumaryl-7-amide optimally at pH 11.0. The L-prolyl-L-phenylalanyl-L-arginine-4-methyl-coumaryl-7-amide hydrolyzing activity of rat stomach kallikrein was inhibited by diisopropyl fluorophosphate and Trasylol, but not by trypsin inhibitors from soybean, lima bean and ovomucoid. These properties of rat stomach kallikrein are different from those of partially purified rat plasma kallikrein, but similar to those of glandular kallikreins from other species. From these results, it was concluded that kallikrein is present in rat stomach and that it can be classified as a glandular kallikrein.
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PMID:Purification and properties of rat stomach kallikrein. 615 23

Tonin is an enzyme found in the rat submaxillary glands which liberates angiotensin II from angiotensinogen, the Skeggs tetradecapeptide renin substrate, and angiotensin I. Tonin hydrolyzes benzoyl-arginine ethyl ester, benzoyl-arginine methyl ester, tosyl-arginine methyl ester, benzoyl-arginine p-nitroanilide and other small synthetic substrates at an optimum ph of 9.0. Tonin shows, however, a great specificity with respect to angiotensin I. Tonin is inhibited by diisopropyl fluorophosphate and phenylmethylsulfonyl fluoride at high concentrations (greater than 10(-2) M) and by soybean trypsin inhibitor and aprotinin. Tonin is thus an esteroprotease of the class of the serine protease with trypsin- and chymotrypsin-like activity. Tonin belongs to the same family of enzyme as glandular kallikrein and the gamma subunit of the nerve growth factor.
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PMID:Tonin, an esteroprotease from rat submaxillary glands. 626 71

Completely inactive renin was isolated from normal human plasma by DEAE-Sepharose column chromatography and Blue-Sepharose column chromatography. This inactive renin had a molecular weight of 54,000 daltons as determined by gel filtration on Ultrogel AcA 44. When the inactive renin was activated by trypsin, its molecular weight decreased to 48,000 daltons. The trypsin-activated renin differed from a native form of active renin in plasma with respect to molecular weight (active renin, 43,000), pI value (active renin, 5.20; trypsin-activated renin, 5.06), km value (active renin, 60 nmoles/liter; trypsin-activated renin, 89 nmoles/liter), Ki value for pepstatin A (active renin, 2.6 mumoles/liter; trypsin-activated renin 5.0 mumoles/liter) and pH profile for angiotensin formation. Glandular kallikrein (human urinary or pig pancreatic) did not activate the inactive renin. When the trypsin-activated renin was treated with glandular kallikrein, its activity was unchanged, but its molecular and kinetic properties except pI value (trypsin-activated kallikrein-treated renin, 4.82) coincided with those of a native form of active renin in plasma. These results indicate that glandular kallikrein does not directly activate inactive renin but participates in the activation process of inactive renin. The results also suggest that inactive renin in human plasma is a renin precursor.
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PMID:Role of glandular kallikrein in the activation process of human plasma inactive renin. 633 49

Inactive renin in rat brains was investigated according to the following experiments. Treatment with either trypsin or glandular kallikrein of the brain tissue caused a rapid and apparent increase in the renin activity at either 0 or 27 degrees C. The molecular weight of the active renin was estimated to be 40,000 daltons, while that of the trypsin-activatable inactive renin was found to be 48,000 or 61,000 daltons on a column chromatography with Sephadex G-100. The contents of the active renin was the highest in the hypothalamus, followed by striatum, thalamus, midbrain, cerebral cortex, medulla oblongata and cerebellum, while the contents of the trypsin-activatable inactive renin was the highest in the hypothalamus, followed by striatum, thalamus, midbrain, cerebellum, cerebral cortex and medulla oblongata. These results suggest that inactive renin(s) exist in the brain. It seems likely that the brain renin-angiotensin system is modulated by the conversion of inactive to active renin(s).
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PMID:[Evidence for the existence of inactive brain renin in the rat. Part I. Activating mechanisms and regional distribution of inactive renin in the brain of normotensive rats]. 639 4

Prokallikrein in the kidney was partially purified with immunoaffinity and DEAE Sephadex A-50 column chromatographies, and its biochemical properties were studied in comparison to three active glandular kallikreins purified from kidney, serum, and urine of the rat. The properties of the enzyme obtained by trypsin activation of prokallikrein were identical with those of active glandular kallikreins from the kidney, serum, and urine of the rat. Apparent molecular weights of prokallikrein, trypsin-activated kallikrein, active renal kallikrein, and glandular kallikrein in rat serum were 38,000 and of active urinary kallikrein, 37,000. Prokallikrein fraction was activated only by trypsin, but not by acidification, pepsin, and rat urinary esterase A treatments. Renal kallikrein, purified in the presence of soybean trypsin inhibitor (SBTI), contained 85% prokallikrein, but the enzymic fraction, purified in the absence of SBTI, contained 23% prokallikrein. Prokallikrein contents of urinary kallikrein and glandular kallikrein in rat serum were 16% and 20% respectively. These results suggest that prokallikrein is produced in the kidney and activated easily by a trypsin-like enzyme. Since rat serum contains active glandular kallikrein, kallikrein in the kidney may be secreted not only into the urine, but also into the blood.
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PMID:Existence of prokallikrein in the kidney. Its biochemical properties compared to three active glandular kallikreins from the kidney, serum, and urine of the rat. 655 28

In pentobarbital-anesthetized rats the lymphatic vessels next to the renal artery and the urinary bladder were cannulated and lymph and urine were collected for 3 h. The kidneys were then washed and removed. Four experimental groups were studied. Kallikrein was measured in lymph, urine, and kidney extracts by a direct radioimmunoassay. Immunoreactive renal and urinary kallikreins were higher in a Na-deficient group. No changes were brought about by furosemide administration or Na supplementation. A very low concentration of immunoreactive kallikrein was found in lymph, with no differences between the groups. In the same urine and kidney extract samples, both total (trypsin-activated) kallikrein and naturally active kallikrein were determined as kininogenase activity in the rat uterus bioassay. Both active and inactive kallikreins were found in kidney and urine, but most of the changes induced by a Na-deficient diet or furosemide administration were restricted to the active form. It is suggested that the lymphatic route in the kidney is probably not an important source of circulating immunoreactive glandular kallikrein.
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PMID:Lymphatic, renal, and urinary kallikreins in the rat. 656 44


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