Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:3.4.15.1 (ACE)
 18,300 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Effect of angiotensin converting enzyme inhibitor (ACEI) and calcium channel blockers (CaB) on renal blood flow (RBF), glomerular filtration rate (GFR), and autoregulation (AR) of RBF were studied on the uninephrectomized spontaneously hypertensive rat (SHR) under the conditions of high (H) and low (L) salt loading. SHR was given with 0.9% or 0.09% NaCl solution as drinking water (GH, GL). Each group was divided into three groups for treatment with enalapril (Enp) and nitredipine (Nit); i.e. Enp group (GHE, GLE), Nit group (GHN, GLN) and control group (GHC, GLC). After 6 weeks, inulin clearance (Cin) was determined and RBF was measured by means of an electromagnetic flow meter. The renal arterial pressure was lowered by clamping and changes in RBF and AR were examined. Cin showed higher values of 1.85 and 1.69 ml/min in GHN and GLN, as compared to be 1.33 and 1.28 ml/min in GHC and GLC (p less than 0.01). Filtration fraction (FF) showed lower values of 0.18 and 0.20 ml/min in GHE and GLE (p less than 0.01), whereas 0.29 and 0.30 in GHC and GLC respectively. RBF was markedly lower at 7.4 ml/min in GLC as compared to 9.9 ml/min in GHC (p less than 0.01). In GH, GHE showed a higher value of 11.6 ml/min, as compared to GHC (p less than 0.01). In GL, comparing with GLC the value was much higher of 12.1 ml/min in GLE (p less than 0.01). AR of RBF diminished in GLC at higher blood pressure as compared to GHC (p less than 0.01). It was maintained at lower blood pressure in GLE (p less than 0.01), but there were no significant differences between four groups; i.e. GLN, GHC, GHE and GHN. In summary, low salt loading reduced RBF and suppressed AR. Enp elevated RBF, lowered FF and caused AR to be maintained even at lower blood pressure. Nit elevated RBF and GFR without changing FF, and did not suppress AR. These results indicate that, in hypertension complicated with moderate dysfunction, both ACEI and CAB are expected to exhibit the beneficial effects on maintenance of renal circulation, despite though the different mechanism.
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PMID:[Effect of angiotensin converting enzyme inhibitor and calcium channel blocker on renal function of spontaneously hypertensive rat]. 180 67

This work evaluates the use of a competitive binding assay using flow-through partial-filling affinity capillary electrophoresis (FTPFACE) to estimate binding constants of neutral ligands to a receptor. We demonstrate this technique using, as a model system, carbonic anhydrase B (CAB, EC 4.2.1.1) and arylsulfonamides. In this technique, the capillary is first partially filled with a negatively charged ligand, a sample containing CAB and two noninteracting standards, and a neutral ligand, then electrophoresed. Upon application of a voltage the sample plug migrates into the plug of negatively charged ligand (L(-)) resulting in the formation of a CAB-L(-) complex. Continued electrophoresis results in mixing between the neutral ligand (L(0)) and the CAB-L(-) complex. L(0) successfully competes out L(-) to form the new CAB-L(0) complex. Analysis of the change in the relative migration time ratio (RMTR) of CAB relative to the noninteracting standards, as a function of neutral ligand concentration, yields a value for the binding constant. These values are in agreement with those estimated using other binding and ACE techniques. Data demonstrating the quantitative potential of this method is presented.
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PMID:Flow-through partial-filling affinity capillary electrophoresis can estimate binding constants of neutral ligands to receptors via a competitive assay technique. 1265 2

Multiple-injection affinity capillary electrophoresis (MIACE) is used to determine binding constants (Kb) between receptors and ligands using as model systems vancomycin and teicoplanin from Streptomyces orientalis and Actinoplanes teichomyceticus, respectively, and their binding to D-Ala-D-Ala peptides and carbonic anhydrase B (CAB. EC 4.2.1.1) and the binding of the latter to arylsulfonamides. A sample plug containing a non-interacting standard is first injected followed by multiple plugs of sample containing the receptor and then a final injection of sample containing a second standard. Between each injection of sample, a small plug of buffer is injected which contains an increasing concentration of ligand to effect separation between the multiple injections of sample. Electrophoresis is then carried out in an increasing concentration of ligand in the running buffer. Continued electrophoresis results in a shift in the migration time of the receptor in the sample plugs upon binding to their respective ligand. Analysis of the change in the relative migration time ratio (RMTR) or electrophoretic mobility (mu) of the resultant receptor-ligand complex relative to the non-interacting standards, as a function of the concentration of ligand yields a value for Kb. The MIACE technique is a modification in the ACE method that allows for the estimation of binding affinities between biological interactions on a timescale faster than that found for standard ACE. In addition sample volume requirements for the technique are reduced compared to traditional ACE assays. These findings demonstrate the advantage of using MIACE to estimate binding parameters between receptors and ligands.
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PMID:Multiple-injection affinity capillary electrophoresis to estimate binding constants of receptors to ligands. 1618 81

An ACE predictive investigation of protein-ligand binding using a highly effective chemometric response surface design technique is presented. Here, K(d) was estimated using one noninteracting standard which relates to changes in the electrophoretic mobility of carbonic anhydrase B (CAB, EC 4.2.1.1) on complexation with the ligand 4-carboxybenzenesulfonamide (CBSA) present in the electrophoresis buffer. Experimental factors including injection time, capillary length, and applied voltage were selected and tested at three levels in a Box-Behnken design. Statistical analysis results were used to create a mathematical model for response surface prediction via contour and surface plots at a given target response (K(d) = 1.19x10(-6) M). As expected, there were a number of predicted solutions that reached our target response based on the significance of each factor at appropriate levels. The adequacy of the model was validated by experimental runs with the predicted model solution (capillary length = 47 cm, voltage = 11 kV, injection time = 0.01 min) presented in detail as an example.
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PMID:Implementation of chemometric methodology in ACE: predictive investigation of protein-ligand binding. 1764 87

Voltage gradient partial-filling affinity capillary electrophoresis (VGPFACE) is used to determine binding constants between carbonic anhydrase B (CAB, E.C.4.2.1.1) and arylsulfonamides, and vancomycin (Van) from Streptomyces orientalis and teicoplanin (Teic) from Actinoplanes teicomyceticus and D-Ala-D-Ala terminus peptides. Two variations of VGPFACE are described herein. In the first technique, the capillary is partially filled with ligand at increasing concentrations followed by a sample containing receptor and two noninteracting standards and electrophoresed in buffer using a voltage gradient that increases from 0 to 25 kV over the duration of the experiment. Upon continued electrophoresis, zones of solution overlap, and equilibrium is established between the ligand and receptor, causing a shift in the migration time of the receptor with respect to the noninteracting standards. This change in migration time is utilized for estimating a binding constant (K(b)). In the second technique, voltage gradient partial-filling multiple-injection ACE (VGPFMIACE), a multiple-injection sequence is used whereby the capillary is partially filled with ligand at increasing concentrations, a noninteracting standard, three or four separate plugs of receptor each separated by small plugs of buffer, and a plug containing a second noninteracting standard; this is then electrophoresed in buffer with a similar voltage gradient. Upon continued electrophoresis, a similar equilibrium is established and a value for K(b) is obtained for the interaction. The VGPFACE technique expands the functionality and potential of ACE as an analytical tool to examine various receptor-ligand interactions.
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PMID:Use of voltage gradient partial-filling affinity capillary electrophoresis to estimate binding constants of ligands to receptors. 1823 12

Partial filling multiple injection affinity capillary electrophoresis (PFMIACE) is used to determine binding constants between vancomycin (Van) from Streptomyces orientalis, teicoplanin (Teic) from Actinoplanes teicomyceticus and ristocetin (Rist) from Nocardia lurida to D-Ala-D-Ala terminus peptides and carbonic anhydrase B (CAB, E.C.4.2.1.1) to arylsulfonamides. Two variations of PFMIACE are described herein. In the first technique, the capillary is partially filled with ligand at increasing concentrations, a non-interacting standard, three or four separate plugs of receptor each separated by small plugs of buffer, a plug containing a second non-interacting standard, and then electrophoresed in buffer. Upon continued electrophoresis, equilibrium is established between the ligand and receptors causing a shift in the migration time of the receptors with respect to the non-interacting standards. This change in migration time is utilized for estimating multiple binding constants (K(b)) for the same interaction. In the second technique, separate plugs of sample containing non-interacting standards, peptide one, buffer, and peptide two, were injected into the capillary column. The capillary is partially filled with a series of buffers containing an antibiotic at increasing concentrations and electrophoresed. Peptides migrate through the column at similar electrophoretic mobilities since their charge-to-mass ratios are approximately the same but remain as distinct zones due to the buffer plug between peptides. Upon electrophoresis, the plug of antibiotic flows into the peptide plugs affecting a shift in the migration time of the peptides with respect to the non-interacting standards occurs due to formation of the of the antibiotic-peptide complex. The shift in the migration time of the peptides upon binding to the antibiotic is used for the Scatchard analysis and measurement of a K(b). The PFMIACE technique expands the functionality and potential of ACE as an analytical tool to examine receptor-ligand interactions. In PFMIACE, a smaller amount of sample is required in the assay compared to both conventional ACE and MIACE. Furthermore, a wide array of data is obtained from a single experiment, thus, expediting the assay of biological species.
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PMID:Partial filling multiple injection affinity capillary electrophoresis (PFMIACE) to estimate binding constants of receptors to ligands. 1907 Dec 88