Search results for " ADR"
showing 10 items of 285 documents
On the mechanism of action of phenylephrine in rat atrial heart muscle
1994
Both in rat left atrial heart and in aortic smooth muscle preparations, phenylephrine (PE) caused a concentration-dependent increase in force of contraction (FC) in the presence of atenolol (10 mumol/l), which was antagonized by phentolamine, prazosin and WB 4101 in a competitive manner. The pA2 values of the antagonists in the cardiac tissue were 10-20fold lower than those in the rat thoracic aorta. In the spontaneously beating right atrium, PE exerted a positive chronotropic action, which was not significantly antagonized by phentolamine or prazosin. It is therefore assumed that the effects of phenylephrine in the left atrium and in the aorta are mediated by different subtypes of alpha 1-…
Modulation of high impulsivity and attentional performance in rats by selective direct and indirect dopaminergic and noradrenergic receptor agonists
2011
Rationale Impulsivity is associated with a number of psychiatric disorders, most notably attention deficit/hyperactivity disorder (ADHD). Drugs that augment catecholamine function (e.g. methylphenidate and the selective noradrenaline reuptake inhibitor atomoxetine) have clinical efficacy in ADHD, but their precise mechanism of action is unclear. Objective The objective of this study is to investigate the relative contribution of dopamine (DA) and noradrenaline (NA) to the therapeutic effects of clinically effective drugs in ADHD using rats selected for high impulsivity on the five-choice serial reaction time task (5CSRTT). Methods We examined the effects of direct and indirect DA and NA rec…
Prognostic factors in stage III-IV adrenocortical carcinomas (ACC): an European Network for the Study of Adrenal Tumor (ENSAT) study
2015
Background: The clinical course of advanced adrenocortical carcinoma (ACC) is heterogeneous. Our study aimed primarily to refine and make headway in the prognostic stratification of advanced ACC.Patients and methods: Patients with advanced ENSAT ACC (stage III or stage IV) at diagnosis registered between 2000 and 2009 in the ENSAT database were enrolled. The primary end point was overall survival (OS). Parameters of potential prognostic relevance were selected. Univariate and multivariate analyses were carried out: model 1 'before surgery'; model 2 'post-surgery'.Results: Four hundred and forty-four patients with advanced ENSAT ACC (stage III: 210; stage IV: 234) were analyzed. After a medi…
Long-Term Clinical Outcomes According to Previous Manifestations of Atherosclerotic Disease (from the FAST-MI 2010 Registry)
2017
IF 3.398; International audience; The prognosis of patients with acute myocardial infarction (AMI) has notably improved in the past 20 years. Using the French Registry of ST-Elevation and Non-ST-elevation Myocardial Infarction (FAST-MI) 2010 registry, we investigated whether previous manifestations of atherosclerotic disease (i.e., previous MI, or a history of any form of atherosclerotic disease) are at truly increased risk compared with those in whom AMI is the first manifestation of the disease. FAST-MI 2010 is a nationwide French registry including 3,079 patients with AMI, among whom 1,062 patients had a history of cardiovascular atherosclerotic disease and 498 patients had a history of …
Impact of 7-Ketocholesterol and Very Long Chain Fatty Acids on Oligodendrocyte Lipid Membrane Organization: Evaluation Via LAURDAN and FAMIS Spectral…
2011
International audience; In the context of multiple sclerosis and X-linked adrenoleukodystrophy, 7-ketocholesterol (7KC) and very long chain fatty acids (C24:0, C26:0) are supposed to induce side effects respectively on oligodendrocytes which are myelin (which is a lipoproteic complex) synthesizing cells. The effects of 7KC (25, 50 mu M), C24:0 and C26:0 (10, 20 mu M) on cell viability and lipid membrane organization were investigated on 158N murine oligodendrocytes. Concerning 7KC and fatty acids (at 20 mu M only):1) cell growth was strongly inhibited; 2) marked induction of cell death was revealed with propidium iodide (PI); 3) no apoptotic cells were found with C24:0 and C26:0 (absence of…
The Role of Transforming Growth Factor-β1 in Airway Inflammation of Childhood Asthma
2013
TGF-beta-targeting structural and inflammatory cells has been implicated in the mechanisms leading to the inflammatory and restructuring processes in asthma, suggesting an impact of TGF-beta1 signaling on the development and persistency of this disease. We investigated the potential early involvement of TGF-beta1 activity in the immunological and molecular mechanisms underlying progression of inflammation in childhood asthma. We evaluated the levels of TGF-beta1 in induced sputum supernatants (ISSs) and the expression of small mother cell against decapentaplegic (Smad) 2 and Smad7 proteins in induced sputum cells (ISCs) from children with intermittent asthma (IA), moderate asthma (MA) and c…
Sulfhydryl G Proteins and Phospholipase A2-Associated G Proteins Are Involved in Adrenergic Signal Transduction in the Rat Pineal Gland
2001
The rat pineal gland with its circadian noradrenaline-regulated melatonin rhythm is an excellent model for studying adrenergic signal transduction with respect to cAMP and cGMP formation. The stimulatory G(s) proteins play a well-established role in this process. In contrast, the potential roles of the inhibitory G(i) proteins, the functionally unclear other G(o) proteins, and a number of G protein subtypes are not known. The present study examines the effects on beta(1)- and beta(1)-plus-alpha(1)-stimulated cAMP and cGMP formation of a number of G protein modulators in rat pinealocyte suspension cultures. The effects of the nitric oxide donor sodium nitroprusside on cGMP were also examined…
Beta-blockers are associated with better long-term survival in patients with Takotsubo syndrome
2022
ObjectiveThe advantage of beta-blockers has been postulated in patients with Takotsubo syndrome (TTS) given the pathophysiological role of catecholamines. We hypothesised that beta-blocker treatment after discharge may improve the long-term clinical outcome in this patient population.MethodsThis was an observational, multicentre study including consecutive patients with TTS diagnosis prospectively enrolled in the Takotsubo Italian Network (TIN) register from January 2007 to December 2018. TTS was diagnosed according to the TIN, Heart Failure Association and InterTAK Diagnostic Criteria. The primary study outcome was the occurrence of all-cause death at the longest available follow-up; secon…
Mechanisms underlying hyperpolarization evoked by P2Y receptor activation in mouse distal colon
2006
In murine colonic circular muscle, ATP mediates fast component of the nerve-evoked inhibitory junction potentials, via activation of P2Y receptors and opening of apamin-sensitive Ca2+-dependent K+ channels. We investigated, using microelectrode recordings, the intracellular events following P2Y-receptor activation by electrical field stimulation or by adenosine 5'-O-2-thiodiphosphate (ADPbetaS), ATP stable analogue. The fast-inhibitory junction potential amplitude was reduced by thapsigargin or ciclopiazonic acid (CPA), sarcoplasmic reticulum Ca2+-ATPase inhibitors, by ryanodine, which inhibits Ca2+ release from ryanodine-sensitive stores, and by 9-(tetrahydro-2-furanyl)-9H-purin-6-amine (S…
Immunoexpression of adrenergic receptors in detrusor from patients with prune belly syndrome: a digital quantification
2010
Abstract Introduction Prune belly syndrome (PBS) presents with large-capacity bladders, high compliance and post-void residual volumes. Operative and conservative treatments are controversial. When histologically compared to normal bladder, bladder outlet obstruction results in an up- or down-regulation of adrenoceptors. Our goal was to study the immunoexpression of adrenoceptors in detrusor from patients with PBS. Materials and methods Bladder domes from PBS patients ( n = 14) were studied (PBG). For normal controls, bladder specimens were obtained at adult surgery ( n = 13) (CG1) and at child autopsy ( n = 5) (CG2). Staining was performed using antibodies to α1a, α1b, α1d and β3 adreno…