Search results for "GMP"
showing 10 items of 121 documents
Regulation of cyclooxygenase-2 expression by cyclic AMP.
2007
Abstract Prostaglandins (PG) regulate many biological processes, among others inflammatory reactions. Cyclooxygenases-1 and -2 (COX-1 and COX-2) catalyse PG synthesis. Since this step is rate limiting, the regulation of COX expression is of critical importance to PG biology. Contrary to COX-1, which is constitutively expressed, COX-2 expression is subject to regulation. For example, COX-2 levels are increased in inflammatory reactions. Many signalling pathways can regulate COX-2 expression, not least those involving receptors for COX products themselves. Analysis of the intracellular signal transducers involved reveals a crucial role for cAMP, albeit as a modulator rather than direct induce…
Effects of SCA40 on human isolated bronchus and human polymorphonuclear leukocytes: comparison with rolipram, SKF94120 and levcromakalim
1996
1. SCA40 (0.1 nM-0.1 mM) produced concentration-dependent suppression of the spontaneous tone of human isolated bronchus (-log EC50 = 6.85 +/- 0.09; n = 10) and reached a maximal relaxation similar to that of theophylline (3 mM). The potency (-log EC50 values) of SCA40 compared to other relaxants was rolipram (7.44 +/- 0.12; n = 9) > SCA40 > or = levcromakalim (6.49 +/- 0.04; n = 6) > SKF94120 (5.87 +/- 0.10; n = 9). 2. When tested against the activity of the isoenzymes of cyclic nucleotide phosphodiesterase (PDE) isolated from human bronchus, SCA40 proved highly potent against PDE III (-log IC50 = 6.47 +/- 0.16; n = 4). It was markedly less potent against PDE IV (4.82 +/- 0.18; n = 4) and …
Alteraciones de la neurotransmisión en hipocampo de ratas hiperamonémicas. papel de la neuroinflamación. modulación por GMPc extracelular
2021
La Encefalopatía Hepática (EH) es un síndrome neuropsiquiátrico complejo producido por un fallo hepático. Cuando el hígado falla se producen hiperamonemia (HA) e inflamación que actúan sinérgicamente produciendo neuroinflamación, lo que da lugar a alteraciones en la neurotransmisión y alteraciones cognitivas y motoras. Estudios anteriores del grupo han demostrado que el aumento de los niveles de GMPc extracelular disminuye la neuroinflamación y revierte las alteraciones cognitivas y motoras observadas en ratas hiperamonémicas. Sin embargo, los mecanismos responsables se desconocían. En la presente tesis doctoral hemos demostrado que la hiperamonemia crónica reduce la respuesta de los recept…
Distribución, función y vías de señalización de los adrenoceptores β a nivel vascular
2014
Se ha analizado la contribución de los diferentes subtipos de adrenoceptores (AR) β (β1, β2 β3) en la vasodilatación, determinando su localización en las diferentes células vasculares y evaluando la implicación de las vías de señalización adenilato ciclasa (AC)/AMPc/PKA y/o NO/guanilato ciclasa soluble (GCs)/GMPc, en dos lechos vasculares representantes de: los vasos de resistencia, como la arteria mesentérica de resistencia (A.M.R.) de rata, y de conductancia, como la aorta de rata. Los resultados obtenidos muestran que, a pesar de que los tres subtipos de AR β se expresan en ambos vasos, su participación en la respuesta funcional, así como la vía de señalización utilizada, es diferente se…
Estimulantes y Activadores de la Guanilato Ciclasa en el Tratamiento del Asma y la Enfermedad Pulmonar Obstructiva Crónica
2022
La enzima guanilato ciclasa soluble (GCs) tras la unión del óxido nítrico (NO), cataliza la conversión del guanosín 5′-trifosfato (GTP) en guanosín 3,5-monofosfato cíclico (GMPc), un segundo mensajero que participa en diversos procesos fisiológicos entre los que se incluyen la relajación muscular, la dilatación de los bronquios y de los vasos sanguíneos, efectos en las rutas de señalización de diferenciación y proliferación celular, efectos antiinflamatorios e inhibición de la agregación de plaquetas. En las vías aéreas de los pacientes con Enfermedad Pulmonar Obstructiva Crónica (EPOC) y asma, dos enfermedades respiratorias caracterizadas por una inflamación crónica y una obstrucción de la…
Nitric Oxide/Cyclic Guanosine Monophosphate Signaling via Guanylyl Cyclase Isoform 1 Mediates Early Changes in Synaptic Transmission and Brain Edema …
2021
Traumatic brain injury (TBI) often induces structural damage, disruption of the blood-brain barrier (BBB), neurodegeneration, and dysfunctions of surviving neuronal networks. Nitric oxide (NO) signaling has been suggested to affect brain functions after TBI. The NO exhibits most of its biological effects by activation of the primary targets-guanylyl cyclases (NO-GCs), which exists in two isoforms (NO-GC1 and NO-GC2), and the subsequently produced cyclic guanosine monophosphate (cGMP). However, the specific function of the NO-NO-GCs-cGMP pathway in the context of brain injury is not fully understood. To investigate the specific role of the isoform NO-GC1 early after brain injuries, we perfor…
The cGMP-gated channel of the rod photoreceptor — a new type of channel structure?
1990
Recents findings from Numa's laboratory reveal that there might exist a wider variety in channel protein structure than originally anticipated. Recently, the cloning has been reported of the first cGMP-gated ion channel, the vertebrate rod photoreceptor which is activated by cGMP acting from the inside of the rod outer segment membrane
Extracellular cyclic GMP and its derivatives GMP and guanosine protect from oxidative glutamate toxicity.
2013
Cell death in response to oxidative stress plays a role in a variety of neurodegenerative diseases and can be studied in detail in the neuronal cell line HT22, where extracellular glutamate causes glutathione depletion by inhibition of the glutamate/cystine antiporter system xc(-), elevation of reactive oxygen species and eventually programmed cell death caused by cytotoxic calcium influx. Using this paradigm, we screened 54 putative extracellular peptide or small molecule ligands for effects on cell death and identified extracellular cyclic guanosine monophosphate (cGMP) as a protective substance. Extracellular cGMP was protective, whereas the cell-permeable cGMP analog 8-pCPT-cGMP or the …
H89 enhances the sensitivity of cancer cells to glyceryl trinitrate through a purinergic receptor-dependent pathway
2014
// Marion Cortier 1, 2, 3 , Rahamata Boina-Ali 1, 2, 3 , Cindy Racoeur 1, 2, 3 , Catherine Paul 1, 2, 3 , Eric Solary 2, 4, 5 , Jean-Francois Jeannin 1, 2, 3 , Ali Bettaieb 1, 2, 3 1 EPHE, Tumor Immunology and Immunotherapy Laboratory, Dijon, F-21000, France 2 Inserm U866, Dijon, F-21000, France 3 EA7269, University of Burgundy, Dijon, F-21000, France 4 Inserm UMR1009, Gustave Roussy Institute, Villejuif F-94805, France 5 University Paris-Sud, Faculty of Medicine, Le Kremlin-Bicetre, F-94800, France Correspondence to: Ali Bettaieb, e-mail: ali.bettaieb@u-bourgogne.fr Keywords: H89, GTN, cancer, purinergic receptors, cGMP Received: October 08, 2014 Accepted: January 09, 2015 Publis…
Papaverine enhances the negative inotropic effect of acetylcholine in rat auricles
1978
The negative inotropic effect of acetylcholine in rat left auricles is enhanced in the presence of the phosphodiesterase inhibitor papaverine. This result favours the idea of a cyclic GMP-mediated action of acetylcholine in the heart.