Search results for "G-protein-coupled receptor"
showing 10 items of 20 documents
The Amino-Terminal Domain of GRK5 Inhibits Cardiac Hypertrophy through the Regulation of Calcium-Calmodulin Dependent Transcription Factors.
2018
We have recently demonstrated that the amino-terminal domain of G protein coupled receptor kinase (GRK) type 5, (GRK5-NT) inhibits NFκB activity in cardiac cells leading to a significant amelioration of LVH. Since GRK5-NT is known to bind calmodulin, this study aimed to evaluate the functional role of GRK5-NT in the regulation of calcium-calmodulin-dependent transcription factors. We found that the overexpression of GRK5-NT in cardiomyoblasts significantly reduced the activation and the nuclear translocation of NFAT and its cofactor GATA-4 in response to phenylephrine (PE). These results were confirmed in vivo in spontaneously hypertensive rats (SHR), in which intramyocardial adenovirus-med…
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…
Analysis of the gastrin-releasing peptide receptor gene in Italian patients with autism spectrum disorders
2008
The gastrin-releasing peptide receptor (GRPR) was implicated for the first time in the pathogenesis of Autism spectrum disorders (ASD) by Ishikawa-Brush et al. [Ishikawa-Brush et al. (1997): Hum Mol Genet 6: 1241-1250]. Since this original observation, only one association study [Marui et al. (2004): Brain Dev 26: 5-7] has further investigated, though unsuccessfully, the involvement of the GRPR gene in ASD. With the aim of contributing further information to this topic we have sequenced the entire coding region and the intron/exon junctions of the GRPR gene in 149 Italian autistic patients. The results of this study led to the identification of four novel point mutations, two of which, that…
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…
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…
Hunting for the high-affinity state of G-protein-coupled receptors with agonist tracers: Theoretical and practical considerations for positron emissi…
2019
Abstract The concept of the high‐affinity state postulates that a certain subset of G‐protein‐coupled receptors is primarily responsible for receptor signaling in the living brain. Assessing the abundance of this subset is thus potentially highly relevant for studies concerning the responses of neurotransmission to pharmacological or physiological stimuli and the dysregulation of neurotransmission in neurological or psychiatric disorders. The high‐affinity state is preferentially recognized by agonists in vitro. For this reason, agonist tracers have been developed as tools for the noninvasive imaging of the high‐affinity state with positron emission tomography (PET). This review provides an…
Molecular cloning of rat G-protein-coupled receptor kinase 6 (GRK6) from brain tissue, and its mRNA expression in different brain regions and periphe…
1997
The rat G-protein-coupled receptor kinase 6 (GRK6) cDNA was cloned from rat brain tissue by a combination of reverse-transcription polymerase chain reactions (RT-PCR), based on homology to the cloned human GRK6, and rapid amplification of cDNA ends (RACE-PCR). We obtained a clone of 2817 bp with an open reading frame of 1731 bp encoding for a protein of 576 amino acids that is 96.7% identical and 97.9% similar to its human counterpart. mRNA was detectable in all brain areas examined. In addition, GRK6 was expressed in skeletal muscle, small intestine, aorta, liver, heart, lung, thymus, stomach, uterus and kidney.
G-protein-coupled receptor kinase 5 polymorphism and Takotsubo cardiomyopathy.
2015
BACKGROUND: Takotsubo cardiomyopathy (TTC) is an increasingly reported clinical syndrome that mimics acute myocardial infarction without obstructive coronary artery disease and is characterized by transient systolic dysfunction of the apical and/or mid-segments of the left ventricle. The syndrome mainly occurs in postmenopausal women with high adrenergic state conditions. Nowadays, the pathophysiology of TTC is not yet known and the possibility of a genetic predisposition is controversial. AIMS: The purpose of this study was to assess the genetic susceptibility to TTC through analysis of the L41Q polymorphism of the G-protein-coupled receptor kinase 5 (GRK5). METHODS AND RESULTS: In a cohor…
Myocardial G Protein Receptor–Coupled Kinase Expression Correlates With Functional Parameters and Clinical Severity in Advanced Heart Failure
2010
In heart failure (HF), sympathetic hyperactivation induces deleterious effects in myocardial β-adrenergic signaling, with receptor down-regulation and desensitization mediated by G protein receptor-coupled kinases (GRKs). We hypothesised that changes in GRK isoforms may be associated with clinical status in advanced HF, using the Interagency Registry for Mechanically Assisted Circulatory Support (INTERMACS) scale.We included 31 patients with advanced HF undergoing transplantation. According to INTERMACS profiles, mRNA and protein levels of GRK isoforms in left ventricular (LV) myocardium were analyzed and compared with nonfailing LV samples.In failing LV myocardium, GRK2 and GRK5 (but not G…
β2- and β1-Adrenoceptor Expression Exhibits a Common Regulatory Pattern With GRK2 and GRK5 in Human and Animal Models of Cardiovascular Diseases.
2015
To explore if genic expression of β(1)- or β(2)-adrenoceptors (ARs) exhibits a common regulatory pattern with G protein-coupled receptor kinase (GRK) 2, GRK3, or GRK5 expression, we determined messenger RNA levels for these genes in different tissues from human and animal models of cardiovascular disease. We measured genic expression by qRT polymerase chain reaction in the left and right ventricles or peripheral blood mononuclear cells from healthy (n = 21), hypertensive (n = 20), heart failure (n = 24), and heart transplanted patients (n = 17) or in left ventricle, peripheral blood mononuclear cells, and kidney from spontaneously hypertensive rats or L-N-methyl-arginine-induced hypertensiv…