Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0020538 (hypertension)
 170,190 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

In porcine aortic endothelial cells, the 21-amino acid peptide endothelin-1 (ET-1) is formed from a 39-amino acid intermediate big endothelin (big ET) by a putative endothelin-converting enzyme (ECE) that cleaves the 39-mer at the Trp21-Val22 bond. Because big ET has less than 1% of the contractile activity of ET-1, inhibition of ECE should effectively block the biological effects of big ET. Big ET injected intravenously into anesthetized rats produces a sustained pressor response that presumably is due to conversion of big ET to ET-1 by ECE. We determined the type of protease activity responsible for this conversion by evaluating the effectiveness of protease inhibitors in blocking the pressor response to big ET in ganglion-blocked anesthetized rats. The serine protease inhibitor leupeptin, the cysteinyl protease inhibitor E-64, and the metalloprotease inhibitors captopril and kelatorphan were ineffective at blocking the pressor response to big ET. However, the metalloprotease inhibitors phosphoramidon and thiorphan both dose-dependently inhibited the pressor response to big ET, although phosphoramidon was substantially more potent than thiorphan. None of the inhibitors blocked the pressor response to ET-1 and none had any effect on blood pressure when administered alone as an i.v. bolus to the ganglion-blocked anesthetized rat. However, phosphoramidon infused intravenously at 20 mg/kg/h for 4 h lowered the mean arterial pressure (MAP) in conscious spontaneously hypertensive rats (SHRs) whereas kelatorphan at the same dose did not. Our results suggest that ECE is a novel metalloprotease and that ECE inhibitors could have therapeutic potential for the treatment of hypertension.
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PMID:Phosphoramidon blocks the pressor activity of big endothelin[1-39] and lowers blood pressure in spontaneously hypertensive rats. 172 58

The standard angiotensin I (Ang I) radioimmunoassay for renin activity determination is a useful clinical tool for the diagnosis of high renin levels in certain cases of hypertension. It depends upon the liberation of Ang I from human plasma angiotensinogen. We considered whether a commercially available synthetic tetradecapeptide (TDP), Asp-Arg-Val-Tyr-Ile-His-Pro-Phe-His-Leu-Leu-Val-Tyr-Ser, would produce authentic Ang I upon incubation with protease from human immunodeficiency virus type 1 (HIV-1). This peptide is also known to be cleaved by renin at the Leu-Leu bond to yield the decapeptide Ang I. When the TDP is incubated with the HIV-1 protease, the peptide is readily hydrolyzed. Product formation is linear with respect to time and enzyme concentration. HPLC analysis of reaction products showed two new peaks, as one would expect from the cleavage of a TDP into a decapeptide and a tetrapeptide. Amino acid analysis of HPLC-purified peaks confirmed that the HIV-1 protease cleaves TDP at the Leu10-Leu11 site to produce the desired decapeptide, Ang I. Production of Ang I by the HIV-1 protease, like human renin, is inhibited in the presence of a protease inhibitor. Implications of the discovery of an HIV-1 protease substrate that produces authentic Ang I are discussed in light of a screening assay for soluble HIV-1 protease inhibitors.
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PMID:Could angiotensin I be produced from a renin substrate by the HIV-1 protease? 179 23

A major incentive in inhibitor research is that control of limited proteolysis constitutes a valuable pharmacological tool. Protease inhibitors have proved to be successful in influencing pathogenesis in many experimental models but a breakthrough to use in human therapy has mainly been restricted to aprotinin and angiotensin converting enzyme (ACE) inhibitors. However, the success of ACE inhibitors as pharmacological tools in hypertension has proved to be a strong stimulant for new protease inhibitor approaches to drug therapy. While emphasis in the search for next generations of ACE inhibitors may move from the circulation renin-angiotensin system to the local tissue systems, including heart, brain and genital tract, persistent and insightful design of renin inhibitors has already yielded highly specific molecules with potent activities in several in vivo models. The development of orally effective long-acting inhibitors will finally allow an evaluation to be made of their therapeutic profile with regard to the family of ACE inhibitors. The close relationship between renin and HIV-1 protease presents an exceptional opportunity for transfer of the knowledge acquired in renin inhibitor development during the past decade, to an accelerated generation of specific HIV-1 protease inhibitors as effective agents in treatment of AIDS. The self-assembly of 2 identical monomers into a symmetrical structure in HIV-1 protease is not only an elegant way to create an active enzyme while encoding a minimal amount of genetic information, but is also in concordance with the bilobular active-site found in mammalian aspartic proteases.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Proteases and their inhibitors: today and tomorrow. 185 40

The coexistence of arterial hypertension and disturbances of haemostasis in pregnant women with EPH-gestosis allow to expect a role of fibrinolysis and kinin-forming systems in pathomechanism of this syndrome. For these reasons blood plasma of 34 patients with EPH-gestosis, 23 patients with normal pregnancy and 19 nonpregnant women was investigated. All pregnant women were in third trimester of pregnancy. The following parameters were investigated: kinin-forming system compounds (kininogens and prokininogenases - biological methods), fibrinolytic activity (plasma euglobulin fibrinolysis time), total plasma protein and fibrinogen concentration, protease inhibitors - antithrombin III, C1-esterase inhibitor, alpha 2-antiplasmin, alpha 1-protease inhibitor and alpha 2-macroglobulin (by electroimmunodiffusion). Furthermore hematocrit was measured. In pregnant women with EPH-gestosis significant increase of high molecular weight kininogen concentration was found (p less than 0.02), decreased fibrinolytic activity (p less than 0.01) and (except alpha 2-antiplasmin) decreased concentration of protease inhibitors (p less than 0.005 - p less than 0.01) were observed. Further statistical analysis demonstrated positive correlation between the concentrations of kininogens and prokallikrein-prokininogenases and between low molecular weight kininogen and plasma euglobulin fibrinolysis time. On the other hand negative correlation between concentrations of those proenzymes and severity of gestosis was observed. The above described phenomena indicate on significance of disturbances of proteolytic enzyme activation in pathogenesis of EPH-gestosis.
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PMID:[Plasma kininogenesis and fibrinolysis in the pathogenesis of EPH gestosis]. 321 8

Blockage of the rat pancreatico-biliary duct (PBDO) for 4 hours and secretin infusion (0.2 CU [Clinical Unit]/kg/hr) caused significant rises in portal serum amylase, cathepsin B levels, pancreatic water content, and pancreatic amylase content as well as lysosomal and mitochondrial fragility. Impaired pancreatic adenylate energy charge levels were also noted. These changes tended to continue for 12 hours after the release of PBDO and disappeared after 24 hours. All the changes induced by PBDO with secretin infusion were no longer observed at 48 hours. The administration of a new potent protease inhibitor, E-3123 at a dose of 5 mg/kg/hr during PBDO markedly attenuated all the parameters examined, exerting a significant protective effect on acinar cells in this model. These results indicate the important roles of subcellular organelle fragility and impaired pancreatic energy metabolism in the pathogenesis of pancreatic injuries induced by common channel obstruction with intraductal hypertension, and also indicate the possible usefulness of E-3123 in the treatment of acute pancreatitis such as gallstone pancreatitis.
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PMID:Effect of short-term pancreatico-biliary duct obstruction with intraductal hypertension on subcellular organelle fragility and pancreatic adenylate energy metabolism in rats: protective effect of a new protease inhibitor, E-3123. 751 90

The current study was done to evaluate the effects of short term (60 minutes) pancreatic biliary duct obstruction (PBDO) with intraductal hypertension (IDH) stimulated by secretin (0.2 clinical unit per kilogram per hour) and caerulein (0.2 microgram per kilogram per hour) plus 30 minutes of temporary pancreatic ischemia (ISCH) produced by ligation of celiac and superior mesenteric artery on the exocrine pancreas and protective effects of a new potent protease inhibitor, ONO3307 in combination with xanthine oxidase inhibitor, allopurinol, in this multifactor related model of acute pancreatitis in rats. Twelve hours after PBDO with IDH plus ISCH, we observed hyperamylasemia (23 +/- 3 units per milliliter) (p < 0.01); moderate pancreatic histologic changes; pancreatic edema (water content--81 +/- 2 percent) (p < 0.02), as well as the impaired amylase (2,889 +/- 328 units per kilogram per hour) (p < 0.01) and cathepsin B output (7 +/- 3 units per kilogram per hour) (p < 0.01) into the pancreatic juice of rats stimulated by caerulein (control group--serum amylase levels, 6 +/- 1 units per milliliter; pancreatic water content, 74 +/- 1 percent. Furthermore, PBDO with IDH plus ISCH caused the redistribution of lysosomal enzyme from lysosomal fraction (12 kilo times gravity pellet; 40 +/- 3 percent; p < 0.01) to zymogen fraction (1.3 kilo times gravity pellet; 38 +/- 3 percent; p < 0.01) (control group--12 kilo times gravity pellet, 59 +/- 2 percent; 1.3 kilo times gravity pellet, 24 +/- 2 percent) and the impaired pancreatic adenylate energy metabolism (0.79 +/- 0.02, p < 0.02) (control group--energy charge equals 0.88 +/- 0.01). Only PBDO with IDH caused no significant changes. Although only ONO3307 or allopurinol therapy showed the partial significant protective effects against pancreatic injuries, improving serum amylase levels, the administration of ONO3307 in combination therapy with allopurinol showed almost complete protective effects against the pancreatic injuries induced by PBDO with IDH plus ISCH (serum amylase levels, 9 +/- 2 units per milliliter; pancreatic water content, 76 +/- 2 percent; amylase and cathepsin B output, 7,127 +/- 946 and 18 +/- 3 units per kilogram per hour; 1.3 kilo times gravity pellet, 28 +/- 2 percent; 12 kilo times gravity pellet, 54 +/- 2 percent, and energy charge equals 0.85 +/- 0.02).(ABSTRACT TRUNCATED AT 400 WORDS)
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PMID:Protective effects of therapy with a protease and xanthine oxidase inhibitor in short form pancreatic biliary obstruction and ischemia in rats. 846 Apr 15

The Otsuka Long-Evans Tokushima fatty (OLETF) rat is an animal model of type 2 diabetes, characterized by abdominal obesity, insulin resistance, hypertension, and dyslipidemia. To elucidate the underlying molecular mechanism of obesity and its related complications, we used representational difference analysis and identified the genes more abundantly and specifically expressed in the visceral adipose tissue (VAT) of obese OLETF rats compared with the diabetes-resistant counterpart, that is, Long-Evans Tokushima Otsuka (LETO) rats. By Northern blot analysis, we confirmed the differential expression of 13 genes, including 3 novel genes. The upregulated expression of well-characterized lipid metabolic enzymes, such as lipoprotein lipase, phosphoenolpyruvate carboxykinase, and cholesterol esterase, were observed in VAT of OLETF rats. We demonstrated the differential expression of secreted proteins in VAT of OLETF rats, such as thrombospondin 1 and contrapsin-like protease inhibitor. In contrast to lipid enzymes, the secreted proteins revealed exclusive mRNA expression and they were not detected in VAT of LETO rats. Furthermore, the novel genes OL-16 and OL-64 were also expressed specifically in VAT of OLETF rats and were absent in that of LETO rats and other tissues, including subdermal and brown adipose tissues. The C-terminal partial amino acid sequence of OL-64 revealed that it showed approximately 40% homology with alpha(1)-antitrypsin and it seemed to be a new member of the serine proteinase inhibitor (SERPIN) gene family. VAT of OLEFT rats had a unique gene expression profile, and the accumulated VAT-specific known and novel secreted proteins may play a role(s) in the pathogenesis of obesity and its related complications.
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PMID:Identification of genes specifically expressed in the accumulated visceral adipose tissue of OLETF rats. 1101 3

A 73-year-old man who had been receiving treatment for hypertension and angina pectoris was admitted to hospital following a transient ischemic attack. He was diagnosed as having chronic disseminated intravascular coagulation (DIC) complicated by a thoracoabdominal aortic aneurysm, and was treated with heparin sodium and a protease inhibitor. Although the DIC was controlled, the patient had to remain hospitalized in order to receive the medication by continuous infusion. Therefore, the heparin sodium and protease inhibitor were replaced by camostat mesilate, a drug suitable for oral administration and widely used for treatment of chronic pancreatitis. The drug proved effective for the chronic DIC, thus allowing the patient to receive regular treatment on an outpatient basis, and improving his quality of life.
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PMID:[Effective use of camostat mesilate for chronic disseminated intravascular coagulation complicated by thoracoabdominal aortic aneurysm]. 1123 31

Reports of metabolic disorders, such as diabetes mellitus and hyperlipidemia, occurring during treatment with protease inhibitor (PI) regimens are prompting patients and providers to try to better understand the links between these disorders and antiretroviral treatments. The Food and Drug Administration (FDA) first reported PI-associated diabetes in June 1997. Diabetes mellitus can be managed by controlling diet and exercise, or by supplementing treatment with oral hypoglycemic drugs. Hypertriglyceridemia has also been associated with PI therapies, and is apparent even in patients experiencing good results from antiretroviral therapy. Treatment for hypertriglyceridemia encompasses monitoring diet and exercise, limiting alcohol, watching hypertension, and quitting smoking. Patients at higher risk for pancreatitis can consider using lipid-lowering drugs and fibric acid derivatives. Alterations in fat distribution have also been linked to PI use, particularly in the back of the neck and upper back, and abdominal area. Researchers have seen evidence of anomalous fat distribution in some patients prior to PI treatment. Management has not consistently been remedied by diet and exercise. Sustaining overall health, reducing blood lipids, and controlling risk factors for cardiovascular disease need to be implemented. Unless the abnormalities are severe and potentially harmful to the patient, it is not commonly recommended to change the PI treatment.
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PMID:Metabolic complications of antiretroviral therapies. 1136 97

Lipodystrophy has been reported by some as one of the side effects of protease inhibitor therapy. However, evidence of lipodystrophy occurring prior to protease therapy supports the premise that this phenomenon has unknown origins. Characteristics of this disorder are the redistribution of fat to unusual places in the body, such as under abdominal muscles or at the base of the neck. Theories are proposed to explain the causes of lipodystrophy, and some of the possible treatments are discussed. Other side effects of protease inhibitor therapy that have been observed are changes in triglycerides, higher cholesterol, diabetes, and high blood pressure. All of these have the potential to lead to heart disease.
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PMID:Therapy side effects update. 1136 37


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