Search results for "Adrenergic receptor"

Control of the production of oxygen intermediates of human polymorphonuclear leukocytes and monocytes by beta-adrenergic receptors.

1983

The control by beta-adrenergic receptors of the production of oxygen radicals by zymosan-stimulated human polymorphonuclear leukocytes (PMN) and monocytes (M phi) was studied in vitro by means of chemiluminescence. In addition we asked whether PMN and M phi exhibit differential sensitivity to beta-adrenergic stimulation. For beta-adrenergic stimulation we applied fenoterol ranging from 10(-5) to 10(-9) M x 2.7. We found a dose-dependent suppression of the production of oxygen radicals, the ID50 being approximately 10(-6) M both for PMN and M phi. By assessment of lactic dehydrogenase release a cytotoxic effect of the drug could be ruled out. When incubated together with the beta-adrenergic …

N-SUBSTITUTION AND á1-ADRENERGIC RECEPTOR AFFINITY OF LAUDANOSINE ANALOGUES

2006

Benzyltetrahydroisoquinoline (BTHIQ) molecules are able to adopt widely differing conformations that depend on the presence or absence of N-substituents. To assess the possible role of BTHIQ conformation on the affinity of these compounds for α 1 -adrenergic receptors, of interest for the management of hypertension, the racemic N-unsubstituted BTHIQ norlaudanosine and a series of N-alkylated derivatives were assessed for binding to rat brain cortical sites labelled with the radioligand [3H]prazosin. The α 1 -adrenergic affinity in this series increased with the bulk of the substituent on the nitrogen atom, from the N-ethyl to the N-propyl analogue. Comparison of these results with published…

Different expression of adrenoceptors and GRKs in the human myocardium depends on heart failure etiology and correlates to clinical variables.

2012

Downregulation of β1- adrenergic receptors (β1-ARs) and increased expression/function of G-protein-coupled receptor kinase 2 (GRK2) have been observed in human heart failure, but changes in expression of other ARs and GRKs have not been established. Another unresolved question is the incidence of these compensatory mechanisms depending on heart failure etiology and treatment. To analyze these questions, we quantified the mRNA/protein expressions of six ARs (α1A, α1B, α1D, β1, β2, and β3) and three GRKs (GRK2, GRK3, and GRK5) in left (LV) and right ventricle (RV) from four donors, 10 patients with ischemic cardiomyopathy (IC), 14 patients with dilated cardiomyopathy (DC), and 10 patients wit…

Effect of noradrenaline and isoproterenol on lipopolysaccharide-induced tumor necrosis factor-alpha production in whole blood from patients with chro…

2005

Increased levels of tumor necrosis factor-alpha (TNF-alpha) correlate with poor prognoses in chronic heart failure (CHF). This study demonstrated that noradrenaline and isoproterenol inhibit TNF-alpha production in patients with CHF in ex vivo whole blood in a dose-dependent fashion. The beta-blocker bisoprolol abolishes this effect.

β2-adrenoreceptors control human skin microvascular reactivity.

2021

Topical α1- and α2-adrenoreceptor (ADRA1 and 2) agonists are effective in alleviating permanent vasodilation and facial erythema associated with rosacea by inducing skin vasoconstriction. Although β-adrenoreceptor (ADRB) antagonists are used off-label for rosacea, pharmacological and pharmacodynamic data pertaining to these receptors in skin micro-vessels are lacking. Objectives: To analyse the expression of different adrenergic receptors and their contribution to vasoreactivity in skin micro-vessels. Small arteries (500-800 μm) and arterioles (<200 μm) were studied in human foreskin tissue. Specifically, ADR-A1, -A2, -B1 and -B2 expression was assayed by immunofluorescence, polymerase chai…

Association between reduced lymphocyte beta-adrenergic receptors and left ventricular dysfunction in young obese subjects

1994

This study was designed to evaluate total (t) and surface (s) beta-adrenergic receptors (BAR) density and their relationships with left ventricular function in young obese subjects. BAR density, plasma insulin, catecholamines and left ventricular function were evaluated in 27 young obese subjects (BMI30.5 kg/m2 for males and27.3 kg/m2 for females) without other risk factors for cardiovascular diseases (smoking, hypertension, diabetes and lipid abnormalities) and in 20 lean controls (BMI25 kg/m2 for males and24.7 kg/m2 for females). Both groups were matched for gender, age and body height. BAR density was evaluated according to Böyum and De Blasi methods. Plasma catecholamines by high perfus…

Lymphocyte beta-adrenergic receptors in young subjects with peripheral or central obesity: relationship with central haemodynamics and left ventricul…

1994

This study was designed to evaluate total (t) and surface (s) β-adrenergic receptor (BAR) density and their relationship with central haemodynamics and left ventricular function in young subjects with central or peripheral obesity. A total of 31 obese subjects (BMI ≥30.5 kg. m−2 for males and >27.3 kg. m−2 for females) aged less than 40 years and without other risk factors for cardiovascular diseases (smoking, hypertension, diabetes and lipid abnormalities) were studied. Nine had peripheral obesity and 22 central obesity according to WHR values; there were 20 lean controls (BMI <25 kg. m−2 for males and <24.7 kg. m−2 for females). Casual (c) and 24 h ambulatory mean blood pressures (MBP-24 …

Changes in Adrenoceptor and GRK Expression in Patients With Chronic Pulmonary Regurgitation.

2019

INTRODUCTION AND OBJECTIVES Pulmonary regurgitation (PR) is a frequent complication after repair of congenital heart disease. Lymphocyte expression of adrenoceptors (β1 and β2) and kinases (GRK2, GRK3, and GRK5) reflects the neurohumoral changes that occur in heart failure (HF). The main objective of this study was to describe the gene expression of these molecules in circulating lymphocytes in patients with severe PR. METHODS A prospective study was conducted to analyze lymphocyte expression of these molecules in patients with severe PR and compare it with expression in healthy controls and patients with advanced HF. RESULTS We studied 35 patients with severe PR, 22 healthy controls, and 1…

Effects of β-adrenergic blockade on EMG signal characteristics during progressive exercise

1984

Myocardial and Peripheral Lymphocytic Transcriptomic Dissociation of β-adrenoceptors and G Protein–coupled Receptor Kinases in Heart Transplantation

2009

Background The genetic expression of adrenergic receptors plays an important pathophysiologic role in heart failure. G protein–coupled receptor kinases (GRKs) desensitize the β-receptor to catecholaminergic stimulation. It has been suggested that their mRNA expression in peripheral lymphocytes could mirror the changes in their myocardial expression in the failing heart, but this relationship between the myocyte and lymphocyte has not been studied in heart transplantation (HT). The objective of this study was to analyze adrenergic receptor and GRK mRNA expression in myocardium and lymphocytes and their correlation. Methods Twenty-three HT patients without evidence of acute rejection or echoc…