Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: EC:3.4.23.15 (renin)
 35,795 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Plasma concentrations of various physiologically important proteins, including transferrin, ceruloplasmin, haptoglobin, transcortin, sex hormone-binding globulin, thyroxin-binding globulin, renin-substrate, fibrinogen, coagulation factors VII and VIII, antithrombin-III, plasminogen, prealbumin, albumin, retinol-binding protein, and lipoprotein fractions, were measured before treatment with oral contraceptives (OCs) and then again after 6 cycles of treatment to measure changes in the daily synthesis rate of 2 proteins, albumin and fibrinogen, under the influence of various OC formulations. Results are presented for 38 women using high-dose (50 mcg estrogen) preparations, 38 using low-dose (30 mcg estrogen preparations), and 20 using a continuous-dose progestagen-only minipill (30 mcg levonorgestrel). Most of the proteins measured showed significant alterations in women using the high-dose OCs. Changes with the lower dose product were less marked, and most proteins were unchanged in women using the minipill. (For example, synthesis rates of fibrinogen, mg/kg/day, for controls, high-, low-, and mini-dose subjects were: 24, 43, 28, and 25 respectively). Data from isotope studies indicated that synthetic estrogens act on liver synthesis and secretion rates for many plasma proteins; hence the clinical associations seen with OC use.
 ...
PMID:Oral contraceptives and plasma protein metabolism. 22 92

The atrial natriuretic factor (ANF) as an osmoregulatory hormone causes a reduction of extracellular fluid volume primarily through stimulation of renal and extrarenal water and sodium elimination. Consequently, ANF counteracts the renin-angio-tensin II-aldosterone (RAAS) and the antidiuretic hormone (ADH) systems at their target organ level. The possible direct interaction of ANF with the hypothalamo-neurohypophyseal ADH system was investigated in conscious ducks and rabbits during conditions of eu- and dehydration. In euhydrated animals, the plasma concentration of ADH remained unchanged during the systemic infusion of species-specific ANF, whereas in dehydrated rabbits but not ducks, the plasma concentration of ADH was significantly decreased. These differences in ADH modulation were supported by the localization of binding sites for radiolabeled ANF at the sites of ADH release, the median eminence (ME) and neurohypophysis (NH) of the rabbit but not duck brain, using receptor-autoradiography. For both species, circumventricular organs lacking a functional blood-brain barrier (BBB) such as the subfornical organ (SFO), the organum vasculosum of the laminae terminalis (OVLT), the pineal and the choroid plexus (ChP), as well as the ependymal lining of the third ventricle (VIII) were labeled specifically. Within the BBB, binding sites for ANF could not be detected in the ADH-synthesizing paraventricular (PVN) and supraoptic nuclei (SON) of either species, however, sites were observed in the anterior median nucleus of the hypothalamus (AM) of the duck brain. In the AM as well as the PVN and ME, the existence of a brain-intrinsic ANF system could be demonstrated for the Pekin duck using immunocytochemistry.(ABSTRACT TRUNCATED AT 250 WORDS)
 ...
PMID:ANF-induced modulation of ADH-release in the rabbit and Pekin duck. 141 Apr 35

Incorporation of beta-alanine or gamma-aminobutyric acid in position P2 of ACHPA or Leu psi [CHOHCH2]Val-based tetrapeptides gave highly active renin inhibitors (compounds V, VI, and XVII) with high specificity for renin and a remarkable stability against chymotrypsin. Replacement of the amide bond between P2 and P3 by isosteres (ketomethylenes, hydroxyethylenes, and the corresponding thio-insertion analogues) led to compounds (VIII-XIII, XVIII, and XIX) with renin inhibitory activity in the nanomolar range. Oral activity was achieved by incorporation of polar functionalities at the N-terminus of beta-alanine-containing tetrapeptides. One of these compounds (XXVIII) was chosen for further studies. This inhibitor demonstrated excellent efficacy and a long duration of action after intravenous and oral administration to cynomolgus monkeys.
 ...
PMID:Substrate analogue renin inhibitors containing replacements of histidine in P2 or isosteres of the amide bond between P3 and P2 sites. 195 45

Renin activity, angiotensin-converting enzyme activity and aldosterone concentration were measured in the plasma of 8 experimental groups of rats: I--sham operated non-treated rats, II--suprachiasmatic nuclei (SCN) lesioned non-treated: III--sham operated + furosemide (4 mg/kg i.p.), IV--SCN lesioned + furosemide, V--shams + 24-hour water deprivation: VI--SCN + 24-hour water deprivation, VII--intact rats + saline: and VIII--intact rats + p-chlorophenylalanine (pCPA, 300 mg/kg, i.p.). No significant changes in basal levels of the three parameters were found after SCN, lesions in comparison with sham operated controls. Furosemide caused a similar increase in all three parameters of both sham and SCN lesioned rats. Similar changes were observed in SCN rats 24 hours after water deprivation and in intact rats 48 hours after serotonin depletion by pCPA: suppressed renin activity together with increased aldosterone concentration. It is concluded that the central serotonergic system and SCN play a similar role in control of the renin-aldosterone system in rats under conditions of negative water-salt balance.
 ...
PMID:Effect on the plasma renin-aldosterone system of lesions to suprachiasmatic nuclei and central serotonin depletion in rats. 303 46

The preparations of sodium 4(S)-[(tert-butyloxycarbonyl)amino]-2,2-difluoro-3(S)- and -3(R)-[(4-methoxyphenyl)amino]-6-methylheptanoates (7a and 7b) from sodium 4(S)-[(tert-butyloxycarbonyl)amino]-2,2-difluoro-3(R)- and -3(S)-hydroxy-6-methylheptanoates (1a and 1b) are described. The key step involves the stereospecific intramolecular displacement via a Mitsunobu reaction for the conversion of a beta-hydroxy hydroxamate to a beta-lactam ring. Compounds 7a and 7b are useful as synthetic intermediates for the preparation of enzyme inhibitors that contain 3(S),4(S)- and 3(R),4(S)-diamino-2,2-difluoro-6-methylheptanoic acid inserts. Angiotensinogen analogues VII and VIII that contain these novel amino analogues of difluorostatine were shown to be inhibitors of the enzyme renin. The alpha,alpha-difluoro-beta-aminodeoxystatine-containing compounds were shown to be weaker inhibitors than the corresponding difluorostatine-containing congeners.
 ...
PMID:alpha,alpha-Difluoro-beta-aminodeoxystatine-containing renin inhibitory peptides. 330 15

Spleen cells from mice immunized with partially purified hog kidney renin were fused with mouse myeloma cells to produce a stable monoclonal hybridoma cell line that synthesizes an antibody against renin. A single monoclonal antibody was chosen for study and has been produced in large quantity and purified by affinity chromatography on protein A-Sepharose. The antirenin, which belongs to the IgG1 subclass, exhibits anticatalytic activity against both hog and rabbit renin. An immunoaffinity column prepared from antibody coupled to Sepharose has been used in the purification of renin from hog kidney. Although renin is quantitatively adsorbed from solution, it can be eluted from the column under gentle conditions. The highly purified renin, with specific activity of 2122 Goldblatt Units/mg protein, exhibits both charge (pH 4.1 to 5.1) and size (38,000 to 42,700) heterogeneity. Hog kidney renin dissociates in the presence of sodium dodecyl sulfate (SDS) and mercaptoethanol to heavy and light chains with molecular weights of 33,700 and 5,800, respectively. In the presence of SDS, a small amount of a nw form of renin is observed with a molecular weight of 19,500 which retains activity on renaturation. The monoclonal antibody should be a useful tool for the study of the renin-angiotensin system and especially for the purification of renin. The hybridoma cell line used in this study (F-32 VIII C4) has been donated to the American Type Culture Collection.
 ...
PMID:Purification of hog kidney renin with immobilized monoclonal antirenin. 637 44

We generated transgenic mice containing a chimeric construct consisting of the alpha-cardiac myosin heavy chain (alpha cMHC) promoter and the human renin (hRen) gene in order to target hRen synthesis specifically to the heart. The construct consisted of three segments: (i) an alpha cMHC DNA segment including 4.5 kb of 5' flanking DNA and an additional 1.1 kb of genomic DNA encompassing exons I-III (non-coding) and the first two introns; (ii) a partial hRen cDNA consisting of exons I-VI; and (iii) a hRen genomic segment containing exons VII through IX, their intervening introns, and 400 bp of 3' flanking DNA. This results in the formation of a 909 bp internal fusion exon consisting of alpha cMHC, polylinker, and hRen sequences. Despite the presence of splice acceptor and donor sites bracketing this exon, transcription of this transgene resulted in a major alternatively spliced mRNA lacking the exon and therefore a majority of the hRen coding sequence. Cloning and sequencing of RT-PCR products from several heart samples from two independent transgenic lines confirmed accurate and faithful splicing of alpha cMHC exon II to hRen exon VII thus bypassing the internal fusion exon. All other exons (alpha cMHC exons I and II and hRen exons VII, VIII and IX) were appropriately spliced. These results are consistent with the hypothesis on exon definition which states that internal exons have a size limitation. Moreover, the results demonstrate that transgenes present in the genome at independent insertion sites and in either a single copy or multiple copies can be subject to exon skipping. The implications for transgene design will be discussed.
 ...
PMID:Inappropriate splicing of a chimeric gene containing a large internal exon results in exon skipping in transgenic mice. 891 7

Phasic oral contraceptives (OCs) provide a physiological approach to contraception and most closely approximate the ideals of a combined OC with the lowest possible doses to avoid the metabolic risks of estrogens and progestins, maximal contraceptive protection, and satisfactory cycle control. Earlier studies have demostrated the decline in myocaridal infarct and thromboembolic disease with reduction of ethinyl estradiol (EE) from 50 to 30 mcg, the correlation between progestin dose and cardiovascular and cerebrovascular deaths, and the effects of progestins derived from 19 nortestosterone in reducing the beneficial high density lipoprotein (HDL) cholesterol. The preparation SH B 264 AB for example provides a 1st phase daily dose of 30 mcg EE and 50 mcg levonorgestrel, a sufficient dosage because of the low probability of ovulation but 1 which attempts to mimic the follicular secretion needed for endometrial growth. Daily doses in the 2nd phase increase to 40 mcg EE and 75 levonorgestrel, each of which is capable alone of inhibiting ovulation. The progestin causes a supplementary hypothalamic inhibition and renders the cervical mucus too viscous for sperm penetration, while the EE augments the hypothalamic inhibitory effect of the progestin, prevents release of luteinizing hormone releasing hormone, and suppresses the luteinizing hormone peak by increasing the pituitary threshold to hypothalamic stimulation. The total dose of SH B 264 AB is at least 30% less than that of other OCs. The Pearl index is 0.0-0.6, not quite as good as that of normal dosed OCs. The duration of menstrual bleeding appears unchanged even after prolonged use, while the amount of bleeding is slightly decreased. Amenorrhea and intermenstrual bleeding are rare. The good cycle control occurs because the steroid levels administered in the triphasic pill mimic those of ovarian secretion, leading to better endometrial development. The effects of triphasic pills on glycemia and insulin levels are very weak and are not statistically significant, while their slight estrogen dominance means that they have very slight effects on the level of HDL cholesterol. They cause a slight increase in triglyceride levels, minimal variation in coagulation parameters, a weak variation in factors VII, VIII, X, and plasminogen, and a slight decrease of antithrombin III. Triphasic OCs induce minimal augmentation in activity of the renin-angiotensin system, and in most cases do not affect blood pressure. Because of their estrogenic dominance, triphasic pills improve acne but may be associated with breast problems, water retention, dysmenorrhea, and premenstrual syndrome with irritability, nervousness, and headache. Triphasic pills are indicated for women beginning OCs, women with poor cycle control under other OCs, women at high cardiovascular risk, women with acne, and women whose current OCs cause oily skin, hirsutism, reduced libido or other symptoms. Contraindications for the triphasic pill in addition to the usual factors include benign breast disease, premenstural syndrome, dysmenorrhea, or polycystic ovarian syndrome.
 ...
PMID:[Pros and cons of triphasic oral contraception]. 1226 12

New epidemiologic data on the vascular risks of oral contraceptives (OCs) were assessed to determine whether the recently introduced low dose triphasic pills offer greater potential safety for OC users than previous formulations. Epidemiologic studies have demonstrated that vascular accidents are less frequent with OCs containing lower doses of both estrogens and progestins. The new triphasic pills have the lowest steroid content of any pills yet developed and less of a progestin climate than low dose monophasic pills. The gradual increases in the progestin dose, from 50 mcg on days 1-6 to 75 mcg on days 7-11 and 125 mcg on days 12-21 and of ethinyl estradiol from 30 mcg on days 1-6 to 40 on days 7-11 and back to 30 on days 12-21 reflect the natural cycle of steroid secretion. The endometrial mucus is better developed than under low dose monophasic pills, permitting better cycle control. Triphasic pills have been shown in all studies to block secretion by the hypothalamus and pituitary of the gonadotropins follicle stimulating hormone and luteinizing hormone, resulting in absence of follicular maturation and of ovulation. Even with the small dose of levonorgestrel, the cervical mucus is rendered inhospitable to capacitation and passage of sperm. The impact on glucose tolerance of low doses of ethinyl estradiol, even after long use, is minimal, but the 19 norsteroids used in most combined pills have a more significant impact. To the directly stimulating effect of progestins on pancreatic insulin secretion is added the development of increased peripheral resistence apparently due to a decrease in the number of insulin receptors in the target tissue. The decrease appears to be dose dependent and proportional to the androgenicity of the progestin. A recent study indicated that triphasic pills caused less of a deterioration in glucose tolerance than standard or low-dose combined OCs or a biphasic formulation. This finding was significant because of the possibility that disturbances in carbohydrate metabolism can favor development of vascular diseases. Triphasic OCs have a slight estrogen dominance, which allows them to maintain favorable levels of high density lipoprotein cholesterol, the fraction believed to provide cardiovascular protection. Similarly, they caused minimal variation on the order of 10-15% in the levels of fibrinogen, factors VII, VIII, and X, plasminogen, and antithrombine III. It has not yet been established with certainty however that changes in the levels of these coagulation factors correspond to changes in actual risk of thromboembolic accidents. Triphasics cause a minimal increase in renin substrate and activity of 12-30% compared to the 30-40% at higher estrogen doses. No significant variation in blood pressure has been observed in triphasic OC users.
 ...
PMID:[Potential advantages of triphasic combined oral contraceptives in the light of recent epidemiological and endocrinometabolic data]. 1231 6

Though heart failure can mainly be caused by systolic or diastolic dysfunction, the impairments of the neurohormonal, immune, and hemostatic systems are observed too. Therefore, it is not easy to determine etiology of the syndrome. Parameters that can be helpful to predict chronic heart failure, to evaluate its course and the risk of complications are still being searched. The aim of this article is to review the recent studies in order to find the links between the coagulation system and the development of chronic heart failure. Stress is a key factor for the development of most diseases including chronic heart failure too. Signals of emotional and physical stress via particular structures trigger an increase in concentrations of the following hormones: noradrenaline, renin, angiotensin II, aldosterone, vasopressin. It is proved that it causes the disorders of the coagulation system: an increase in the following factors of plasma coagulation (fibrinogen, VII, VIII, fibrinopeptide A, thrombin-antithrombin complex), fibrinolysis (D-dimer), endothelium (interleukin 1, endothelin 1, vascular cell adhesion molecules, endothelial growth factor), platelet activity (von Willebrand factor, intercellular adhesion molecules, platelet factor 4, P-selectin, thromboxane A(2), thromboglobulin, CD63P) and cytokines (tumor necrosis factor, interleukin 6) and decrease in E-selectin. The role of particular coagulation factors for the development of chronic heart failure has not been understood yet. Thus, it is necessary to carry out further studies.
 ...
PMID:The coagulation system changes in patients with chronic heart failure. 2125


1 2 Next >>