Adenosine plays an important neuroprotective role in brain, usually mediated by the activation of adenosine A(1) receptors. Prolonged activation of a G-protein-coupled receptor generally leads to the partial loss of the responsiveness of ...
PubMed
1. Intravenous injection of paeoniflorin, a glycoside purified from the root of Paeonia lactiflora, reversed guanethidine-induced hypotension in Wistar rats. 2. Pretreatment with the adenosine A1 receptor antagonist 8-cyclopentyl-1,3-dipropylxanthine inhibited this effect of paeoniflorin in a dose-dependent manner. 3. The action of ...
Primary rat hippocampal neurons show spontaneous [Ca(2+)(i)]-oscillations in Mg(2+)-free medium, which depend on excitatory signal transmission by N-methyl-D-aspartate /[alpha]-amino-3-hydroxy-5-methylisoxazole-4-propionate receptors modulated by inhibitory [gamma]-amino-n-butyric acid type A receptors. Volatile anesthetics depress these oscillations by ...
A class of innate receptors called the triggering receptors expressed on myeloid cells (TREM) has been discovered and shown to be involved in innate inflammatory responses. The TREM family has been found in the chicken genome and consists of one activating gene (TREM-A1) and two inhibitory ...
Sepsis is a leading cause of multiorgan dysfunction and death in hospitalized patients. Dysregulated inflammatory processes and apoptosis contribute to the pathogenesis of sepsis-induced organ dysfunction and death. A(1) adenosine receptor (A(1)AR) activation reduces ...
, because the estrogen receptor (ER) antagonist tamoxifen and the androgen receptor (AR) antagonist-mediatedneuroprotection,respectively.Transcriptionalactivityisrequiredfortheneuroprotectiveaction,becausedominant negative forms of the receptors that block the transcriptional activity of the ER and AR prevent ...
E-print Network
AMPA receptors and NMDA receptors are the main subtypes of ionotropic glutamate receptors in the vertebrate central nervous system. Accumulating evidence demonstrates that two serine sites, S831 and S845, on the AMPA receptor GluA1 subunit, are phosphorylation-regulated and ...
A novel class of innate receptors called the triggering receptors expressed on myeloid cells (TREM) has been discovered and shown to be involved in innate inflammatory responses. The TREM family has been found in the chicken genome and consists of one activating gene (TREM-A1) and two ...
Technology Transfer Automated Retrieval System (TEKTRAN)
We have shown that A1 adenosine receptors (A1ARs) are cytoprotective against renal tubular necrosis and apoptosis both in vivo and in vitro. To study the role of A1AR numbers on renal epithelial cell survival, we stably overexpressed the human A1 receptor in a porcine renal ...
Synthesis and physicochemical properties of N-benzyl pyrimido[2,1-f]purinediones are described. These derivatives were synthesized by the cyclization of 7-chloropropylo-8-bromo-1,3-dimethyl- or 1,3-dipropyl xanthine derivatives with corresponding (un)substituted benzylamines. Dipropyl derivatives were obtained under microwave irradiation conditions either. The obtained compounds (1-20) were ...
organization of the adenosine A2A receptor gene by molecular and bioinformatics analyses. Brain Res. 2004 Mar, Peterfreund RA, Fuxe K, Vincent JD, Lledo PM. Activation of adenosine A1 and A2A receptors modulates dopamine, Gies EK, Gelb CR, Peterfreund RA. Agonist-induced desensitization of A2B ...
Experimental evidence in animal models suggests that adenosine is involved in the regulation of digestive functions. This study examines the influence of adenosine on the contractile activity of human colon. Reverse transcription-polymerase chain reaction revealed A(1) and A(2a) receptor expression in colonic ...
Transcriptional activation of the human CYP1A1 gene (coding for cytochrome P450 1A1) is mediated by the aryl hydrocarbon receptor. In the present study we have examined interaction of the ginsenoside Rg1 and Rb1 with the carcinogen activation pathway ...
Two reactive metabolites were identified in vivo for the dual A(2A)/A(1) receptor antagonist 1. Two strategies were implemented to successfully mitigate the metabolic liabilities associated with 1. Optimization of the arylindenopyrimidines led to a number of amide, ether, and amino analogs having comparable in vitro and in vivo ...
It has been shown that adenosine deaminase (ADA; EC 3.5.4.4) behaves as an ecto-enzyme anchored to membrane proteins, among them A(1) adenosine receptors (A(1)Rs). Bovine ADA interacts with A(1)Rs from many species and regulates agonists binding to receptors in an ...
The induction of CYP1A1 is mediated via the aromatic hydrocarbon (Ah) receptor. Studies from our laboratory show CYP1A1 induction by picrotoxin and phenobarbital which prompted us to examine if other ligands of the gamma-aminobutyric acid (GABA) receptor could also induce ...
Pharmacological characterization of adenosine A(1) and A(2A) receptors in human brain caudate nucleus membranes led to non-cooperative binding of radiolabelled ligands. In human caudate nucleus but not in cortex, the agonist binding to A(1) receptors was modulated by the agonist binding to A(2A) ...
Background and purpose. This study was undertaken to investigate the role of adenosine in the modulation of the contractility in mouse duodenum and to characterize the adenosine receptor subtypes involved. Experimental approach. RT-PCR was used to investigate the expression of mRNA encoding for A(1) , A(2A) , A(2B) and A(3) receptors. Contractile ...
Phage A1 isolated from the rhizosphere of Lotus corniculatus was studied. It had a very narrow host range, as it was active only against Mesorhizobium loti HAMBI 1129. Phage A1 was classified as belonging to C Bradley's group bacteriophages. The latent period of A1 was 120-130 min and a burst ...
Excessive maternal caffeine consumption can lead to fetal and neonatal pathology, but the underlying mechanisms have not been determined. Here, we report that low doses of caffeine generate seizures when applied in conjunction with brief anoxic episodes in the hippocampus of neonatal rats in vitro. In control conditions, brief (4-6 minutes) anoxic episodes reversibly depressed evoked synaptic ...
Hydroxysteroid sulfotransferase SULT2A1 catalyzes the sulfation of hydroxysteroids and xenobiotics. It plays an important role in the detoxification of hydroxyl-containing xenobiotics and in the regulation of the biological activities of hydroxysteroids. ERR? is an orphan member of the nuclear receptor superfamily ...
Highly malignant human gliomas overexpress the G-protein-coupled chemoattractant receptor formyl peptide receptor (FPR1), which promotes tumor progression when activated. Our previous studies demonstrated that necrotic glioblastoma cells release chemotactic agonist(s) that activate FPR1 on viable tumor cells. In ...
All four adenosine receptor subtypes have been shown to play a role in cardioprotection, and there is evidence that all four subtypes may be expressed in cardiomyocytes. There is also increasing evidence that optimal adenosine cardioprotection requires activation of more than one receptor subtype. The purpose of this study was to ...
Adenosine regulates a wide variety of physiological processes including heart rate, vasodilation and inflammation through the activation of specific cell surface adenosine receptors. In addition to these well-established roles of adenosine, recent genetic and pharmacological research has implicated adenosine as an important regulator in bone remodeling. ...
Although the neuromodulator adenosine plays an important role in many central nervous system physiological and pathological processes, the properties and mechanisms of extracellular adenosine production are still unclear. In previous work, we determined that two forms of adenosine release can be evoked in the molecular layer of the cerebellum: one independent of ionotropic glutamate ...
Clinical studies implicate adenosine acting on esophageal nociceptive pathways in the pathogenesis of noncardiac chest pain originating from the esophagus. However, the effect of adenosine on esophageal afferent nerve subtypes is incompletely understood. We addressed the hypothesis that adenosine selectively activates esophageal nociceptors. Whole cell perforated patch-clamp ...
Cytochrome P450 1a1 (Cyp1a1) is a phase I xenobiotic-metabolizing enzyme, the expression of which is mainly driven by the aryl hydrocarbon receptor (AhR). Cyp1a1 messenger (m)RNA is labile. Our study indicates that 1-nitropyrene (1-NP) highly induced ...
AIB1 which stands for Amplified in Breast cancer, codes for a protein that is a member of the steroid receptor coactivator (SRC) family. AIB1 is amplified in approximately 5-10% of breast cancers and the mRNA and protein over expressed in >30% of breast c...
National Technical Information Service (NTIS)
Evidence for an Aryl Hydrocarbon Receptor-Mediated Cytochrome P450 Autoregulatory Pathway-1 cells through transient transfection with various cytochrome P450 isoforms. Expression of cytochromes P450 1A1, 1A2, or 1B1 reduced AhR-mediated luciferase reporter activity, whereas cytochrome P450 2
Adenosine Released by Astrocytes Contributes to Hypoxia-Induced Modulation of Synaptic Transmission of excitatory synaptic transmission me- diated by activation of presynaptic A1 adenosine receptors. The glia-specific metabolic inhibitor fluorocitrate (FC) was as effective as the A1 adenosine ...
Human polymorphonuclear leukocytes adhesion to endothelial cells during the early stage of inflammation leads to cell surface externalization of Annexin A1 (AnxA1), an effector of endogenous anti-inflammation. The antiadhesive properties of AnxA1 become operative to finely tune polymorphonuclear leukocytes ...
Our previous studies showed that stimulation of adenosine A(1) receptors located in the nucleus of the solitary tract (NTS) exerts counteracting effects on the iliac vascular bed: activation of the adrenal medulla and ?-adrenergic vasodilation vs. sympathetic and vasopressinergic vasoconstriction. Because NTS ...
Bile acids activate a nuclear receptor, farnesoid X receptor (FXR), that induces bile salt export pump (BSEP) but inhibits cholesterol 7alpha-hydroxylase (CYP7A1) gene transcription in the liver. Guggulsterone, a plant sterol that lowers serum cholesterol, has been shown to antagonize FXR ...
Hyperbilirubinemia remains a common condition in neonates. The constitutive androstane receptor (CAR) is an orphan nuclear receptor that has been shown to participate in the activation of the uridine diphosphate-5?-glucuronosyltransferase 1A1 (UGT1A1) ...
PubMed Central
The gene encoding cholesterol 7alpha-hydroxylase (CYP7A1) is tightly regulated to control bile acid synthesis and maintain lipid homeostasis. Recent studies in mice suggest that bile acid synthesis is regulated by the fasted-to-fed cycle, and fasting induces CYP7A1 gene expression in parallel to the induction of ...
The in vivo characterization of a dual adenosine A(2A)/A(1) receptor antagonist in several animal models of Parkinson's disease is described. Discovery and scale-up syntheses of compound 1 are described in detail, highlighting optimization steps that increased the overall yield of 1 from 10.0% to 30.5%. Compound 1 is a potent ...
Neurons in the central amygdala (CeA) co-express dynorphin and corticotropin-releasing hormone (CRH). Moreover, the activity of both the CRH and dynorphin systems in CeA is altered by alcohol treatments, effects suggesting interactions between the CRH and dynorphin systems. Thus, the objectives of the present study were to investigate the effects of (1) ...
Harman is a common compound in several foods, plants and beverages. Numerous studies have demonstrated its mutagenic, co-mutagenic and carcinogenic effects; however, the exact mechanism has not been fully identified. Aryl hydrocarbon receptor (AhR) is a transcription factor regulating the expression of the carcinogen-activating enzyme; cytochrome P450 ...
Energy Citations Database
The function, trafficking and synaptic signaling of AMPA receptors are tightly regulated by phosphorylation. Ca(2+)/calmodulin-dependent kinase II (CaMKII) phosphorylates the GluA1 AMPA receptor subunit at Ser831 to increase single-channel conductance. We show that CaMKII increases the conductance of native heteromeric AMPA receptors ...
Adenosinergic systems have been implicated in anxiety-like states, as caffeine can induce a state of anxiety in human beings. Caffeine is an antagonist at A(1) and A(2) adenosine receptors but it remains unclear whether anxiety is mediated by one or both of these. As the adenosinergic system is rather conserved, we opted to pursue these questions using zebrafish, a widely used ...
G protein-activated K(+) channels composed of Kir3 (GIRK) subunits contribute to regulation of heart rate and excitability. Opening of these channels in myocytes is increased by binding of G(??) upon activation of muscarinic M(2) receptors (M(2)-R) or A(1) adenosine receptors ...
The Toll gene encodes an interleukin 1 receptor-like protein that mediates dorsoventral polarity in the Drosophila embryo. The possible involvement of Toll or Toll-like proteins also in the Drosophila immune response was investigated by overexpressing Toll10B, a constitutively active mutant protein, in the Drosophila blood cell line mbn-2. Induction of the ...
To understand more about the factors influencing the cleavage of immunoglobulin A1 (IgA1) by microbial IgA1 proteases, a recombinant human IgA2/IgA1 hybrid molecule was generated. In the hybrid, termed ...
IgA nephropathy (IgAN), the most common glomerulonephritis, is characterized by mesangial IgA1-containing immunodeposits, proliferation of mesangial cells, and matrix expansion. Clinical onset is frequently heralded by synpharyngitic hematuria, macroscopic hematuria during an upper-respiratory tract infection. Clinical and laboratory data support a ...
Cholesterol 7?-hydroxylase (CYP7A1) encodes for the rate-limiting step in the conversion of cholesterol to bile acids in the liver. In response to acute cholesterol feeding, mice upregulate CYP7A1 via stimulation of the liver X receptor (LXR) ?. However, the effect of a chronic high-cholesterol ...
A novel series of arylindenopyrimidines were identified as A(2A) and A(1) receptor antagonists. The series was optimized for in vitro activity by substituting the 8- and 9-positions with methylene amine substituents. The compounds show excellent activity in mouse models of Parkinson's disease when dosed orally. PMID:20347304
Induction of the innate immune pathways is critical for early antiviral defense but there is limited understanding of how teleost fish recognize viral molecules and activate these pathways. In mammals, Toll-like receptors (TLR) 7 and 8 bind single-stranded RNA of viral origin and are activated by s...
Adenosine plays a dual role on acetylcholine (ACh) release from myenteric motoneurons via the activation of high-affinity inhibitory A(1) and facilitatory A(2A) receptors. The therapeutic potential of adenosine-related compounds for controlling intestinal motility and inflammation, prompted us to investigate ...
Sulindac, a widely used non-steroidal anti-inflammatory drug (NSAID), has been shown to inhibit chemically induced carcinogenesis in animal models. In the present study, we have investigated the molecular mechanism by which sulindac affects the activity and expression of the enzymes that mediate the initial detoxification steps of many environmental carcinogens, the ...
It has been hypothesized that an interaction among adenosine A(1) receptors, protein kinase C (PKC) activation, and ATP-sensitive potassium channels (K(ATP)) mediates ischemic preconditioning in experiments on different animal species. The purpose of this study was to determine if activation of ...
Cardiac vegetations result from bacterium�platelet adherence, activation and aggregation, and are associated with increased morbidity and mortality in infective endocarditis. The GPIIb/IIIa and Fc?RIIa platelet receptors play a central role in platelet adhesion, activation and aggregation induced by endocarditis pathogens such as ...
The A1 domain of von Willebrand factor (VWF-A1) plays a crucial role in hemostasis and thrombosis by initiating platelet adhesion at sites of arterial injury through interactions with the platelet receptor glycoprotein Ib alpha (GPIbalpha). Here we report that murine VWF-A1 supports limited ...
Cytochrome P450 1A1 (CYP1A1) is induced by halogenated and polycyclic aromatic hydrocarbons following activation of the aryl hydrocarbon receptor (AhR). Protein kinase C (PKC) has been implicated in the regulation of this response. In tissue culture, induction of PKC ...
Adaptive forms of synaptic plasticity that reduce excitatory synaptic transmission in response to prolonged increases in neuronal activity may prevent runaway positive feedback in neuronal circuits. In hippocampal neurons, for example, glutamatergic presynaptic terminals are selectively silenced, creating "mute" synapses, after periods of increased neuronal ...
The psychomotor stimulant effects of caffeine, the most widely consumed psychoactive substance, are mediated through its antagonism of extracellular adenosine receptors in the basal ganglia. In the absence of caffeine, adenosine stimulates inhibitory striatopallidal neurons that suppress motor activity by binding to A2A receptors, ...
NSDL National Science Digital Library
Methylxanthines of either natural or synthetic origin have a number of interesting pharmacological features. Proposed mechanisms of methylxanthine-induced pharmacological effects include competitive antagonism of G-coupled adenosine A(1) and A(2A) receptors and inhibition of phosphodiesterases. A number of studies have indicated that ...
Mitochondrial sterol 27-hydroxylase (CYP27A1) catalyzes oxidative cleavage of the sterol side chain in the bile acid biosynthetic pathway in the liver and 27-hydroxylation of cholesterol in most tissues. Recent studies suggest that 27-hydroxycholesterol (27-HOC) activates liver orphan receptor alpha (LXRalpha) and ...
Spinal cord injury (SCI) triggers the re-expression of inhibitory molecules present in early stages of development, contributing to prevention of axonal regeneration. Upregulation of EphA receptor tyrosine kinases after injury suggest their involvement in the nervous system's response to damage. However, the expression profile of their ephrinA ligands after SCI is unclear. In ...
The appreciation that the inflammatory reaction does not �spontaneously� finish, but rather that inflammatory resolution is an active phenomenon brought about by endogenous anti-inflammatory agonists opens multiple opportunities for a reassessment of the complexity of inflammation and its main mediators. This review dwells on one of these pathways, the one centred around ...
Perforated patch clamp recordings were performed on cultured superficial neonatal rat dorsal horn (DH) spinal cord neurones in order to study the presynaptic modulation of GABA release at unitary synaptic connections. Since ATP can be coreleased with GABA at about two-thirds of GABAergic synapses between DH neurones, and can be rapidly metabolized to adenosine in the extracellular space, we ...
Acute liver injury is associated with renal insufficiency, whose mechanism may be related to activation of the hepatorenal reflex. We previously showed that intrahepatic adenosine is involved in activation of the hepatorenal reflex to restrict urine production in both healthy rats and in rats with cirrhosis. The aim of the present study was to test the ...
Atrazine (ATR) remains a widely used broadleaf herbicide in the United States despite the fact that this s-chlorotriazine has been linked to reproductive abnormalities in fish and amphibians. Here, using zebrafish we report that environmentally relevant ATR concentrations elevated zcyp19a1 expression encoding aromatase (2.2 �g/L), and increased the ratio ...
OBJECTIVE: The antiinflammatory properties of the female sex hormone estrogen have been linked to a reduced incidence of cardiovascular disease. In the present study, we addressed whether estrogen could activate vasculoprotective mechanisms via annexin A1 (AnxA1) mobilization in human ...
... 105.044560 The Orphan Nuclear Receptor NR4A1 Regulates Insulin-Like 3 Gene Transcription in Leydig Cells1Nicholas M. ... 2765; ...
NBII National Biological Information Infrastructure
Cytochrome P450 (P450)1A1 plays a critical role in the metabolic activation and detoxification of polycyclic aromatic hydrocarbons (PAHs), many of which are potent human carcinogens. In this investigation, we tested the hypothesis that MC elicits persistent induction of CYP1A1 expression in human hepatoma cells (HepG2) and that this ...
Purines are important modulators of bone cell biology. ATP is metabolized into adenosine by human primary osteoblast cells (HPOC); due to very low activity of adenosine deaminase, the nucleoside is the end product of the ecto-nucleotidase cascade. We, therefore, investigated the expression and function of adenosine receptor subtypes ...
Following transient global cerebral ischemia (GCI), spontaneous electrocortical activity resumes from the isoelectric line through a sequence of "bursts" of activity alternating with periods of electrical "suppression," commonly referred to as the post-ischemic burst suppression (BS) pattern. Several lines of evidence suggest that BS reflects an impairment ...
The effects of the selective adenosine A1 receptor agonist N6-cyclopentyladenosine (CPA; 1 and 0.1 mg/kg, i.p.) and the A1 selective antagonist 8-cyclopentyl-1,3-dipropylxanthine (CPX) have been examined on the electroencephalogram (EEG) of intact rats. From four EEG leads the EEG signal was subjected to Fast Fourier Transform and ...
In the in vitro perfused rectal gland of the dogfish shark (Squalus acanthias), the adenosine analogue 2-chloroadenosine (2Clado) completely and reversibly inhibited forskolin-stimulated chloride secretion with an IC50 of 5 nM. Other A1 receptor agonists including cyclohexyladenosine (CHA), N-ethylcarboxamideadenosine (NECA) and ...
similar and the two can be used interchange- ably. The alcohol used here was cyclohexanol. The molar
Mucociliary clearance, vital to lung clearance, is dependent on cilia beat frequency (CBF), coordination of cilia, and the maintenance of periciliary fluid. Adenosine, the metabolic breakdown product of ATP, is an important modulator of ciliary motility. However, the contributions of specific adenosine receptors to key airway ciliary motility processes are unclear. We ...
Chemical transmitters released from astrocytes, termed gliotransmitters, modulate synaptic transmission and neuronal function. Using astrocyte-specific inducible transgenicmice (dnSNARE mice), we have demonstrated that inhibiting gliotransmission leads to reduced activation of adenosine A1 receptors ...
AMPA receptors consist of a family of hetero-oligomeric (tetrameric) receptors arising from four genes, each of which encodes a distinct receptor subunit (GluA1-4). Recombinant homo-tetrameric AMPA receptors, comprising four identical subunits, are functionally ...
This study investigates the proliferative effect of adenosine (ADO) in cultured mesangial cells, and the possible mediation of A1 and/or A2 receptors in this proliferative effect of ADO. ADO (10(-5) M) induced a significant increase in the [3H]thymidine incorporation into DNA with respect to quiescent cells. This increase was similar to that obtained with the ADO ...
To ascertain the presence of adenosine receptors in the trout testis, cells isolated from testes at different spermatogenetic stages were cultured in the presence or absence of adenosine, adenosine receptor agonists, or antagonists and of cAMP analogs, for up to 20 min, or 20 hr, or 4.5 days. Cyclic AMP production was then assayed or 3H-thymidine ...
Axon pathfinding and synapse formation rely on precise spatiotemporal localization of guidance receptors. However, little is known about the neuron-specific intracellular trafficking mechanisms that underlie the sorting and activity of these receptors. Here we show that loss of the neuron-specific v-ATPase subunit ...
are ana- lysed in this paper; zinc finger Zif268-DNA complex [18], -receptor-DNA complex, MyoD transcription activation do- main-DNA complex [19], human-chicken estrogen receptor- DNA complex [20], MAT A1 In this subsection, we will describe six different protein-DNA complexes: (1) Zinc finger ...
Sympathetic nervous system regulation by the ?(1)-adrenergic receptor (AR) subtypes (?(1A), ?(1B), ?(1D)) is complex, whereby chronic activity can be either detrimental or protective for both heart and brain function. This review will summarize the evidence that this dual regulation can be mediated through the ...
Amyloid-? peptide (A?) concentration in CSF is potentially a diagnostic and therapeutic target for Alzheimer's disease (AD). The purpose of this study was to clarify the elimination mechanism of human A?(1-40) [hA? (1-40)] from CSF. After intracerebroventricular (ICV) administration, [(125) ...
During sleep, the mammalian CNS undergoes widespread, synchronized slow wave activity (SWA) that directly varies with prior waking duration (Borbely, 1982;Dijk et al., 1990a). When sleep is restricted, an enhanced SWA response follows in the next sleep period. The enhancement of SWA is associated with improved cognitive performance (Huber et al., 2004c), but it is unclear ...
Dioxins are nearly ubiquitous environmental contaminants that are produced as byproducts during industrial processes, including the bleaching of paper and textiles. Contamination of animal bedding material with dioxins has been a concern for both laboratory and farm animals. The objective of this study was to determine whether the presence of cotton balls, provided to mice for enrichment, caused ...
The aim of this study is to set up single molecular secreted phosphoprotein 1 (SPP1) upstream invasive network of lung adenocarcinoma. This paper proposed an integrated method based on linear programming and a decomposition procedure with integrated analysis of the significant function cluster using Kappa statistics and fuzzy heuristic clustering. Our study proved that only modules appearing in ...
CYP1A1, an enzyme of the cytochrome P450 superfamily, is the most important xenobiotic-metabolizing enzyme of the placenta for which relevant inducible activity has been demonstrated throughout pregnancy. CYP1A1 metabolizes several drugs and compounds widely used in pharmacotherapy or present ...
We have previously shown that the p38 MAPK inhibitor SB203580 (SB) significantly induced Cyp1a1 gene expression at the mRNA and activity levels, whereas it dramatically inhibited the induction of Cyp1a1 by TCDD in murine hepatoma Hepa 1c1c7 cells. However, the molecular mechanisms involved were not investigated yet. Therefore, the ...
Cytochrome P-450 1A1 (CYP1A1) is known to be induced by aromatic hydrocarbons, such as 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), through activation of the aryl hydrocarbon receptor (AhR). We found that p38 MAP kinase inhibitors (SB203580 and SB202190; 40 microm each; ...
Activation of the adenosine A1(A1) receptor, Gi protein, and ATP-sensitive K+ (KATP)-channel system has been shown to play an important role in the cardioprotective effects of ischemic preconditioning in dogs. The present study was undertaken to elucidate the possible ...
Modulation of glutamatergic neurotransmission by metabotropic glutamate2/3 (mGlu2/3) receptor agonists effectively treats seemingly diverse neuropsychiatric illness such as generalized anxiety disorder and schizophrenia. Activation of adenosine A1 heteroceptors, like mGlu2 autoreceptors, decreases glutamate release in the medial ...
1. Previous studies have shown that 8-phenyltheophylline (8-PT), a non-selective antagonist at adenosine A1- and A2-receptors, can ameliorate the severity of glycerol-induced acute renal failure (ARF) in the rat. In the present study we have examined the effects of an antagonist with selectivity for adenosine ...
The effects of N6-cyclopentyladenosine (CPA), a highly selective agonist for adenosine A1 receptors, on retention of one-trial inhibitory avoidance behavior were examined in mice. Water-deprived animals were trained to avoid drinking by pairing foot-shock with licks from a water spout. Retention was measured as the suppression of ...
TCDD increases CYP1A1 transcription by activating the Ah receptor, which binds to a specific DNA recognition sequence within an enhancer upstream of the CYP1A1 gene. Cycloheximide produces an additional increase of transcription. Nuclear runoff analyses of mouse hepatoma cells stably transfected with plasmids ...
Binding affinities of 28 adenosine analogs at A1 adenosine receptors (rat whole brain membranes, (/sup 3/H)N6-cyclohexyladenosine, CHA), and at A2 adenosine receptors (rat striatal membranes, (/sup 3/H)NECA) were compared to their EC/sub 25/ values for decreasing heart rate and increasing coronary flow in the isolated rat heart. Heart rate (an ...
Nonstructural (NS) proteins of autonomous parvoviruses can repress expression driven by heterologous promoters, an activity which thus far has not been separated from their cytotoxic effects. It is shown here that, in transient transfection assays, the NS-1 protein of the parvovirus minute virus of mice (MVMp) activates the promoter of the human ...
... Accession Number : ADP008338. Title : Synthesis and Opioid Activity of Dynorphin A(1-13) Analogs Substituted at Positions 2 and 4. ...
DTIC Science & Technology
Distinct from most alginate-assimilating bacteria that secrete polysaccharide lyases extracellularly, a gram-negative bacterium, Sphingomonas sp. A1 (strain A1), can directly incorporate alginate into its cytoplasm, without degradation, through a �superchannel� consisting of a mouth-like pit on the cell ...
Diminished myocardial function can be seen in chronic coronary stenosis (CS) even in the presence of normal resting myocardial blood flow. We hypothesized that adenosine contributes to myocardial depression in this setting, predominantly through activation of the A(1) adenosine receptor. To test this hypothesis we used aminophylline, a nonselective ...
Adenosine, acting through its receptors, exerts effects on almost all organ systems, influencing a diversity of physiological responses, including the inhibition of neurotransmitter release, the modulation of cardiac rhythmicity and contractility, and the potentiation of IgE-dependent mediator release. Adenosine receptors belong to the G protein-coupled ...
Uranium is a naturally occurring heavy metal found in the Earth's crust. It is an alpha-emitter radioactive element from the actinide group that presents both radiotoxicant and chemotoxicant properties. Some studies revealed that uranium could affect the reproductive system. To distinguish chemical versus radiological effects of uranium on the metabolism of the steroids in the testis, rats were ...
Transcriptional activation of the murine Cyp1a-1 (cytochrome P(1)450) gene by inducers such as 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) (dioxin) requires the aromatic hydrocarbon (Ah) receptor and the interaction of an inducer-receptor complex with one or more of the Ah-responsive elements ...
The pre�T cell receptor (TCR) is expressed early during T cell development and imposes a tight selection for differentiating T cell progenitors. Pre-TCR�expressing cells are selected to survive and differentiate further, whereas pre-TCR? cells are �negatively� selected to die. The mechanisms of pre-TCR�mediated survival are poorly understood. ...
The capacity for long-term changes in synaptic efficacy can be altered by prior synaptic activity, a process known as "metaplasticity." Activation of receptors for modulatory neurotransmitters can trigger downstream signaling cascades that persist beyond initial receptor activation and may thus ...
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