Search results for "Sodium"
showing 10 items of 1605 documents
Acetylcholine overflow during infusion of a high potassium-low sodium solution into the perfused chicken heart in the absence and presence of physost…
1977
1. The effect of infusion of a modified Tyrode's solution (“high K+-low Na+ solution”) into the isolated chicken heart on the content of acetylcholine in the tissue and the overflow of acetylcholine were compared to those evoked by vagal stimulation. 2. The release of acetylcholine was measured over 15-min periods of either stimulation of the vagus nerves (40 V, 1 ms) at 20 Hz or of infusion of the high K+-low Na+ solution (108 mM K+, 44 mM Na+). 3. Both stimuli caused a maximum overflow of acetylcholine in the first few minutes whether or not 10−6 M physostigmine was present. The overflow was maintained during the vagal stimulation at a constant rate of at least 35% the initial rate, where…
Oral mucosal peeling related to dentifrices and mouthwashes: A systematic review
2018
Background The aim of this systematic review was to summarise the clinical information available about oral mucosal peeling (OMP) and to explore its aetiopathogenic association with dentifrices and mouthwashes. Material and Methods PICOS outline: Population: subjects diagnosed clinically and/or pathologically. Intervention: exposition to oral hygiene products. Comparisons: patients using products at different concentrations. Outcomes: clinicopathological outcomes (primary) and oral epithelial desquamation (secondary) after use. Study design: any. Exclusion criteria: reports on secondary or unpublished data, in vitro studies. Data were independently extracted by two reviewers. Results Fiftee…
Artrial Natriuretic Peptide Concentrations in Preeclampsia
1989
During pregnancy various humoral and functional mechanisms were recognized, that regulate the water and electrolyte household. In preeclampsia, increased water-sodium retention results from a variety of pathophysiological changes in the endocrinological system. There are also organ-specific changes, such as renal clearance reduction up to 30% in comparison to normal pregnancy. For many years, physiologists expected to find additional cardial mechanisms that influence homeostasis. In 1981, de Bold [3] identified ANP a new humoral factor that leads to increased water and sodium excretion. The influence of ANP in preeclampsia has been the subject of controversial discussion.
A hybrid stimulation strategy for suppression of spiral waves in cardiac tissue
2011
International audience; Atrial fibrillation (AF) is the most common cardiac arrhythmia whose mechanisms are thought to be mainly due to the self perpetuation of spiral waves (SW). To date, available treatment strategies (antiarrhythmic drugs, radiofrequency ablation of the substrate, electrical cardioversion) to restore and to maintain a normal sinus rhythm have limitations and are associated with AF recurrences. The aim of this study was to assess a way of suppressing SW by applying multifocal electrical stimulations in a simulated cardiac tissue using a 2D FitzHugh-Nagumo model specially convenient for AF investigations. We identified stimulation parameters for successful termination of S…
Beta-2-glycoprotein I is growth regulated and plays a role as survival factor for hepatocytes
2004
Beta-2-glycoprotein I (beta(2)GPI) is mainly produced by the liver and is found in plasma partially associated to lipoproteins. Although various properties have been attributed to this protein, its physiological role remains still unclear. We investigated its expression in cultured liver cells and in regenerating liver. Expression studies in HepG2 cells demonstrate that beta(2)GPI mRNA is regulated in a cell cycle-dependent manner, with very low expression in low cycling conditions and increasing levels in proliferating cells. p21 WAF-dependent growth arrest, induced by butyrate treatment, down-regulate beta(2)GPI mRNA levels. Immunolocalization in normal rat liver shows a non-homogeneous p…
Relaxation and cGMP formation in response to sildenafil and sodium nitroprusside in saphenous veins from normotensive and hypertensive patients1
2002
Abstract Background This study was designed to measure cyclic guanosine 3′5′ monophosphate (cGMP) formation and relaxation response to sildenafil given either alone or in combination with sodium nitroprusside in saphenous veins obtained from normotensive and hypertensive patients. Methods Saphenous vein rings were obtained from 13 hypertensive and nine normotensive patients undergoing coronary artery bypass surgery. The vein rings were suspended in organ bath chambers for isometric recording of tension. The effect of sildenafil on sodium nitroprusside-induced cGMP formation was also assessed. Results Sildenafil (10 nmol/L to 100 μmol/L) and sodium nitroprusside (0.01 to 100 nmol/L) caused c…
Early urinary sodium trajectory and risk of adverse outcomes in acute heart failure and renal dysfunction.
2021
Introduction and objectives: Urinary sodium (UNa+) has emerged as a useful biomarker of poor clinical outcomes in acute heart failure (AHF). Here, we sought to evaluate: a) the usefulness of a single early determination of UNa+ for predicting adverse outcomes in patients with AHF and renal dysfunction, and b) whether the change in UNa+ at 24 hours (Delta UNa24 h) adds any additional prognostic information over baseline values. Methods: This is a post-hoc analysis of a multicenter, open-label, randomized clinical trial (IMPROVE-HF) (ClinicalTrials.gov NCT02643147) that randomized 160 patients with AHF and renal dysfunction on admission to a) the standard diuretic strategy, or b) a carbohydra…
Possible role of cyclic AMP in the relaxation process of mammalian heart: effects of dibutyryl cyclic AMP and theophylline on potassium contractures …
1976
The effect of dibutyryl cyclic AMP (DB-c-AMP; 3 X 10(-4)-3 X 10(-3) M) on electrically induced twitch and high potassium (142.4 mM KCl)-induced contracture tension was studied in papillary muscles from normal and reserpinized cats ([Ca]0 1.8 mM; 25 degrees C; pH 7.4). In both groups of preparations, the increase in twitch tension evoked by DB-c-AMP was accompanied by an abbreviation of the time to peak force and of relaxation time. In the same preparations, the high potassium contracture was markedly depressed by DB-c-AMP in a concentration-dependent manner. Similar results were obtained with the N6-monobutyryl derivative of cyclic AMP. The relaxing effects of the cyclic nucleotides on KCl …
Effects of sodium fluoride on the mechanical activity in mouse gastric preparations.
2005
The aim of the present study was to investigate the responses induced by sodium fluoride (NaF) on gastric mechanical activity, using mouse whole-stomach preparations. The mechanical activity was recorded in vitro as changes of intraluminal pressure. In most of the preparations, NaF induced a tetrodotoxin-insensitive biphasic effect characterized by early relaxation followed by slowly developing contractile response. The contraction was dependent on the concentration of NaF, whereas the relaxation was observed at only 10–30 mmol/L NaF. The contractile effect was significantly reduced by nifedipine (an L-type Ca2+channel blocker), ryanodine or ruthenium red (inhibitors of Ca2+release from sar…
Molecular adaptations of voltage-gated sodium ion channel related proteins after fatiguing stretch-shortening cycle exercise
2008
Dystrophin associated protein alpha-syntrophin is known to interact with voltage-gated sodium ion channel (NaCh). Dystrophin is known to be sensitive to eccentric muscle actions. For this reason, the function of the NaChs might also be affected. Molecular adaptations of dystrophin, alpha-syntrophin and NaChs were investigated after fatiguing stretch-shortening cycle (SSC) exercise, which consisted of unilateral jumps on a sledge apparatus. Muscle biopsies were taken from the vastus lateralis muscle of eight healthy subjects immediately after (IA) and 2 days after (2D) the exercise to analyze mRNA levels and immunohistochemical staining patterns. SSC exercise resulted in decreased isometric …