Search results for "glibenclamide"
showing 10 items of 26 documents
Mechanisms involved in the increased sensitivity of the rabbit basilar artery to atrial natriuretic peptide in diabetes.
2017
Atrial natriuretic peptide (ANP) is a vasodilator with significant regional differences and controversial effects in the cerebral circulation, a vascular bed particularly prone to diabetes-induced complications. The present study has investigated how alloxan-induced diabetes modifies the mechanisms involved in the response of the rabbit basilar artery to ANP. ANP (10(-12) -10(-7) M) relaxed precontracted basilar arteries, with higher potency in diabetic than in control rabbits. In arteries from both groups of animals, endothelium removal reduced ANP-induced relaxations. Inhibition of NO-synthesis attenuated ANP-induced relaxation but this attenuation was lower in diabetic than in control ra…
Modulation of adrenergic responses of human vas deferens by K+ channel inhibitors.
2010
Objectives The present study was designed to evaluate the role of K + channels in the adrenergic responses of human vas deferens as well as the intervention of dihydropyridine-sensitive Ca 2+ channels on modulation of adrenergic responses by K + channel inhibitors. Methods Ring segments of the epididymal part of the vas deferens were taken from 32 elective vasectomies and mounted in organ baths for isometric recording of tension. We then studied the effects of K + channel blockers on neurogenic and norepinephrine-induced contractile responses. Results Addition of tetraethylammonium (TEA, 10 −3 M), a nonspecific K + channel blocker, or charybdotoxin (10 −7 M), a nonselective inhibitor of lar…
The Effect of Methanolic Leaf Extract of Boerhavia diffusa Linn. (Nictaginaceae) on the Activities of Antidiabetic, Anti-inflammatory and Antioxidant…
2018
Diabetic therapeutic potentiality of methanol extract of stem leaves of Boerhavia diffusa was investigated following in-vivo study models in streptozotocin-induced diabetic rat. Methanol extract of stem leaves of Boerhavia diffusa exerted the glucose lowering effect an increase in serum insulin level on 28st day of postadministration. In addition to a higher expression of insulin receptor A. The extract treatment or glibenclamide for 28 days significantly (p<0.05) reduced HbA1c. Boerhavia diffusa L. or glibenclamide for 28 days show no damaging effect on red blood count and hemoglobin when compared to the control group. Significant (p<0.05) increase in platelet count and white blood cell c…
Involvement of prostacyclin and potassium channels in the diabetes-induced hyporeactivity of the rabbit carotid artery to B-type natriuretic peptide
2012
The relation between diabetes and stroke is bidirectional: diabetes is an important risk factor for ischemic stroke, and acute stroke frequently induces hyperglycemia. On the other hand, plasma B-type natriuretic peptide (BNP) levels are raised in diabetes and stroke. The purpose was to study how alloxan-induced diabetes might modify the effects of BNP in rabbit carotid arteries and the mechanisms involved in such actions. To do this, isometric tension in isolated rabbit carotid artery was recorded and prostanoids release and plasma NT-proBNP were measured by enzyme immunoassay. BNP induced a relaxation of phenylephrine-precontracted carotid arteries, and this relaxation was lower in diabet…
Comparison of the Effects of Glibenclamide on Metabolic Parameters, GLUT1 Expression, and Liver Injury in Rats With Severe and Mild Streptozotocin-In…
2012
Background and Objective. Glucose transport via GLUT1 protein could be one of additional mechanisms of the antidiabetic action of sulfonylureas. Here, the GLUT1 gene and the protein expression was studied in rats in the course of severe and mild streptozotocin-induced diabetes mellitus and under glibenclamide treatment. Material and Methods. Severe and mild diabetes mellitus was induced using different streptozotocin doses and standard or high fat chow. Rats were treated with glibenclamide (2 mg/kg daily, per os for 6 weeks). The therapeutic effect of glibenclamide was monitored by measuring several metabolic parameters. The GLUT1 mRNA and the protein expression in the kidneys, heart, and l…
The relaxant effects of cromakalim (BRL 34915) on human isolated airway smooth muscle
1992
Cromakalim (BRL 34915) is a potassium channel opener with therapeutic potential as a bronchodilator in asthma. Cromakalim (0.1–30 μmol/l) inhibited the spontaneous tone of human isolated bronchi n a concentration-related manner being nearly as effective as isoprenaline or theophylline. The order of relaxant potencies (expressed as -log10 IC50 mol/l; mean ±SEM) was isoprenaline (7.29 ± 0.27; n = 8) > cromakalim (5.89 ± 0.12; n = 7) > theophylline (4.07 ±0.13; n = 10). In human bronchi where tone had been raised by addition of histamine (0.1 mmol/l), acetylcholine (0.1 mmol/l) or leukotriene D4 (LTD4, 0.1 μmol/l), the relaxant effect of cromakalim was substantially reduced. Cromakalim suppres…
Analysis of the Modifications in the Spectral and Morphologic Regularity during Ventricular Fibrillation Produced by Physical Exercise and the Use of…
2015
Chronic physical exercise modifies cardiac activity improving response to malignant arrhythmia and, specifically, ventricular fibrillation (VF). Drug administration as glibenclamide, responsible for K + ATP channel blocking, is also generating a positive response against fibrillation.
Synthesis and first evaluation of new 18F-labelled sulfonylureas for the determination of the beta-cell status in vivo
2001
The syntheses and first in vitro evaluations for two fluoride bearing sulfonylurea derivatives are reported. Firstly, the tolbutamide derivative 1-[4-(2-[18F]fluoroethoxy)benzenesulfonyl]-3-butyl urea (2-[18F]fluoroethyl-tolbutamide) could be labeled efficiently with [18F]fluoride. Subsequently, the glibenclamid derivative N-(2-(4-(N-((cyclohexylamino)carbonyl)sulfonylamino)phenyl)ethyl) 2-(5-chloro-2-[18F]fluorethoxy)phenyl) formamide (2-[18F]fluoroethyl-glibenclamide) was labeled with [18F]fluoride in high yields. Its ability to induce insuline secretion from rat beta-cells in relation to the original glibenclamide was determined.
Synthesis and evaluation of a glibenclamide glucose-conjugate: a potential new lead compound for substituted glibenclamide derivatives as islet imagi…
2007
The search for novel SUR1-ligands originates from the idea to influence the in vivo behaviour by adding new structural moieties to the glibenclamide structure while preserving its binding affinity. Important application of novel conjugates might be their use as radioactively labelled tracer probes in the non-invasive investigation of the islet mass. It is known that the imaging quality of a tracer could be improved by increasing its hydrophilicity, which leads to a reduced plasma protein binding and diminished the unspecific uptake by various organs. In this study the glucose molecule was chosen as a substitute of glibenclamide to enhance hydrophilicity. As expected glucose conjugation lead…
Potassium channels contribute to the increased sensitivity of the rabbit carotid artery to hydrogen sulfide in diabetes
2019
Abstract Hydrogen sulfide (H2S) is a potential endothelium-derived hyperpolarizing factor (EDHF) and adventitium- or adipocyte-derived relaxing factor (ADRF) which vasorelaxant action is mediated by potassium channels. H2S could also play an important role in the pathophysiology of diabetic cardiovascular complications. The present study has investigated the influence of alloxan-induced diabetes on the role of potassium channels mediating the relaxant response of the rabbit carotid artery to NaHS, a donor of H2S. NaHS (10−8-3 × 10−5 M) relaxed phenylephrine-precontracted carotid arteries, with higher potency in diabetic than in control rabbits. The selective blockers of potassium channels c…