Abstract:
:1. The effects of adenosine A1 receptor stimulation on basal and histamine-stimulated levels of intracellular free calcium ion concentration ([Ca2+]i) have been investigated in primary astrocyte cultures derived from neonatal rat forebrains. 2. Histamine (0.1 microM-1 mM) caused rapid, concentration-dependent increases in [Ca2+]i over basal levels in single type-2 astrocytes in the presence of extracellular calcium. A maximum mean increase of 1,468 +/- 94 nM over basal levels was recorded in 90% of type-2 cells treated with 1 mM histamine (n = 49). The percentage of type-2 cells exhibiting calcium increases in response to histamine appeared to vary in a concentration-dependent manner. However, the application of 1 mM histamine to type-1 astrocytes had less effect, eliciting a mean increase in [Ca2+]i of 805 +/- 197 nM over basal levels in only 30% of the cells observed (n = 24). 3. In the presence of extracellular calcium, the A1 receptor-selective agonist, N6-cyclopentyladenosine (CPA, 10 microM), caused a maximum mean increase in [Ca2+]i of 1,110 +/- 181 nM over basal levels in 30% of type-2 astrocytes observed (n = 53). The size of this response was concentration-dependent; however, the percentage of type-2 cells exhibiting calcium increases in response to CPA did not appear to vary in a concentration-dependent manner. A mean calcium increase of 605 +/- 89 nM over basal levels was also recorded in 23% of type-1 astrocytes treated with 10 microM CPA (n = 30). 4. In the absence of extracellular calcium, in medium containing 0.1 mM EGTA, a mean increase in [Ca2+]i of 504 +/- 67 nM over basal levels was recorded in 41% of type-2 astrocytes observed (n = 41) after stimulation with 1 microM CPA. However, in the presence of extracellular calcium, pretreatment with the A1 receptor-selective antagonist, 8-cyclopentyl-1,3-dipropylxanthine, for 5-10 min before stimulation with 1 microM CPA, completely antagonized the response in 100% of the cells observed. 5. In type-2 astrocytes, prestimulation with 10 nM CPA significantly increased the size of the calcium response produced by 0.1 microM histamine and the percentage of responding cells. Treatment with 0.1 microM histamine alone caused a mean calcium increase of 268 +/- 34 nM in 41% of the cells observed (n = 34). After treatment with 10 nM CPA, mean calcium increase of 543 +/- 97 nM was recorded in 100% of the cells observed (n = 33). 6. These data indicate that adenosine Al receptors couple to intracellular calcium mobilization and extracellular calcium influx in type-1 and type-2 astrocytes in primary culture. In addition, the simultaneous activation of adenosine Al receptors on type-2 astrocytes results in an augmentation of the calcium response to histamine H1 receptor stimulation.
journal_name
Br J Pharmacoljournal_title
British journal of pharmacologyauthors
Peakman MC,Hill SJdoi
10.1111/j.1476-5381.1995.tb15004.xsubject
Has Abstractpub_date
1995-07-01 00:00:00pages
801-10issue
5eissn
0007-1188issn
1476-5381journal_volume
115pub_type
杂志文章abstract::1. Receptor phosphorylation and down-regulation by protein kinases may be a key event initiating desensitization. The present studies were designed to investigate the effect of a potent protein kinase C (PKC) activator, phorbol 12,13-dibutyrate (PDBu), on antinociception induced by intrathecal (i.t.) administration of...
journal_title:British journal of pharmacology
pub_type: 杂志文章
doi:10.1111/j.1476-5381.1996.tb15610.x
更新日期:1996-08-01 00:00:00
abstract::Amyotrophic lateral sclerosis (ALS) is the most common motor neuron neurodegenerative disease. Although it has been classically considered as a disease limited to the motor system, there is increasing evidence for the involvement of other neural and non-neuronal systems. In this review, we will discuss currently exist...
journal_title:British journal of pharmacology
pub_type: 杂志文章,评审
doi:10.1111/bph.15202
更新日期:2020-07-16 00:00:00
abstract::1 A rat isolated gastric mucosal preparation was used to monitor histamine output and acid secretion during stimulation by different secretagogues. 2 In non-stimulated preparations, spontaneous histamine output decreased over 450 min. 3 Stimulation of secretion with 4 (5)-methylhistamine or dibutyryl cyclic adenosine ...
journal_title:British journal of pharmacology
pub_type: 杂志文章
doi:10.1111/j.1476-5381.1982.tb09190.x
更新日期:1982-05-01 00:00:00
abstract::1 The effect of thiopentone, methohexitone, urethane and ketamine on the uptake and release of gamma-aminobutyric acid (GABA) and D-aspartate by rat thalamic slices has been investigated. 2 A high, supra-anaesthetic concentration of methohexitone increased the uptake of both D-aspartate and GABA. 3 None of the anaesth...
journal_title:British journal of pharmacology
pub_type: 杂志文章
doi:10.1111/j.1476-5381.1982.tb08776.x
更新日期:1982-01-01 00:00:00
abstract::1 Very highly purified (greater than 100,000 u/mg) slow reacting substance of anaphylaxis (SRS-A) has been prepared by reversed phase high pressure liquid chromatographic (HPLC) techniques. 2 High resolution liquid chromatography suggests that SRS-A may exist in at least three distinct forms which are possible tautome...
journal_title:British journal of pharmacology
pub_type: 杂志文章
doi:10.1111/j.1476-5381.1980.tb10696.x
更新日期:1980-01-01 00:00:00
abstract:BACKGROUND AND PURPOSE:A functional link between seizure-induced P-glycoprotein overexpression at the blood-brain barrier and therapeutic failure has been suggested by several studies using rodent epilepsy models and human epileptic tissue. Recently, we reported that interference with the mechanisms that up-regulate P-...
journal_title:British journal of pharmacology
pub_type: 杂志文章
doi:10.1111/j.1476-5381.2010.00765.x
更新日期:2010-07-01 00:00:00
abstract::1 The relationship of agonist efficacy to the rate of G protein-coupled receptor signaling desensitization is controversial. 2 Expressing inwardly rectifying potassium channels (GIRKs) in Xenopus oocytes, we have devised a signaling assay that clearly identifies CB1 cannabinoid receptor agonists with low intrinsic eff...
journal_title:British journal of pharmacology
pub_type: 杂志文章
doi:10.1038/sj.bjp.0705792
更新日期:2004-06-01 00:00:00
abstract::1. The relative proportions of beta 1- and beta 2-adrenoceptors were determined by radioligand binding studies in three different rat myocardial preparations: membranes prepared from rat ventricle (ventricular membranes), membranes prepared from rat isolated ventricular myocytes (myocyte membranes), and myocytes isola...
journal_title:British journal of pharmacology
pub_type: 杂志文章
doi:10.1111/j.1476-5381.1995.tb16384.x
更新日期:1995-09-01 00:00:00
abstract::G protein-coupled receptors are one of the most actively studied families of proteins. However, despite the ubiquity of protein dimerization and oligomerization as a structural and functional motif in biology, until the last decade they were generally considered as monomeric, non-interacting polypeptides. For the meta...
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pub_type: 杂志文章,评审
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更新日期:2008-03-01 00:00:00
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doi:10.1111/bph.13161
更新日期:2015-07-01 00:00:00
abstract:BACKGROUND AND PURPOSE:Quercetin lowers plasma glucose, normalizes glucose tolerance tests and preserves pancreatic β-cell integrity in diabetic rats. However, its mechanism of action has never been explored in insulin-secreting β-cells. Using the INS-1 β-cell line, the effects of quercetin were determined on glucose- ...
journal_title:British journal of pharmacology
pub_type: 杂志文章
doi:10.1111/j.1476-5381.2010.00910.x
更新日期:2010-10-01 00:00:00
abstract::1. Human big-endothelin-1 (big-ET-1) and endothelin-1 (ET-1) are equipotent as pressor agents and produce a significant change in mean arterial blood pressure (MAP) in anaesthetized guinea-pigs (2 nmol kg-1: peak delta MAP: 23 +/- 6 mmHg and 26 +/- 5 mmHg, respectively). 2. Unlike big-ET-1, big-endothelin-3 (big-ET-3)...
journal_title:British journal of pharmacology
pub_type: 杂志文章
doi:10.1111/j.1476-5381.1991.tb12448.x
更新日期:1991-10-01 00:00:00
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journal_title:British journal of pharmacology
pub_type: 杂志文章
doi:10.1038/sj.bjp.0701310
更新日期:1997-08-01 00:00:00
abstract::Chronic heart failure (HF) is characterized by left ventricular (LV) structural remodeling, impaired function, increased circulating noradrenaline (NA) levels and impaired responsiveness of the myocardial beta-adrenoceptor (betaAR)-adenylyl cyclase (AC) system. In failing hearts, inhibition of the sodium/proton-exchan...
journal_title:British journal of pharmacology
pub_type: 杂志文章
doi:10.1038/sj.bjp.0706714
更新日期:2006-05-01 00:00:00
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journal_title:British journal of pharmacology
pub_type: 杂志文章
doi:10.1038/sj.bjp.0704198
更新日期:2001-08-01 00:00:00
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journal_title:British journal of pharmacology
pub_type: 杂志文章
doi:10.1111/j.1476-5381.1992.tb14508.x
更新日期:1992-11-01 00:00:00
abstract::1. We have investigated the cellular target of K(+) channel blockers responsible for the inhibition of the EDHF-mediated relaxation in the rat mesenteric artery by studying their effects on tension, smooth muscle cell (SMC) membrane potential and endothelial cell Ca(2+) signal ([Ca(2+)](endo)). 2. In arteries contract...
journal_title:British journal of pharmacology
pub_type: 杂志文章
doi:10.1038/sj.bjp.0704348
更新日期:2001-11-01 00:00:00
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更新日期:2014-02-01 00:00:00
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pub_type: 杂志文章,评审
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更新日期:2015-04-01 00:00:00
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journal_title:British journal of pharmacology
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doi:10.1111/j.1476-5381.2009.00553.x
更新日期:2010-02-01 00:00:00
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journal_title:British journal of pharmacology
pub_type: 杂志文章
doi:10.1111/j.1476-5381.1991.tb12278.x
更新日期:1991-04-01 00:00:00
abstract::1. Inhibition of nitric oxide generation with Nw-nitro-L-arginine (nitroarginine) reduced vasodilator responses to bradykinin and acetylcholine and enhanced those to nitroprusside in the rat isolated perfused kidney, preconstricted with phenylephrine. 2. Inhibition of cyclo-oxygenase with indomethacin, decreased the v...
journal_title:British journal of pharmacology
pub_type: 杂志文章
doi:10.1111/j.1476-5381.1992.tb14513.x
更新日期:1992-11-01 00:00:00
abstract::1. In cortical slices from rat brain incubated in a medium containing the irreversible cholinesterase inhibitor, soman (0.005 mM) and a high concentration of KCl (25 mM), atropine exerts a stimulating action on the release of acetylcholine (ACh).2. Two possible explanations for this action were examined. Atropine migh...
journal_title:British journal of pharmacology
pub_type: 杂志文章
doi:10.1111/j.1476-5381.1971.tb07068.x
更新日期:1971-04-01 00:00:00
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journal_title:British journal of pharmacology
pub_type: 杂志文章
doi:10.1038/sj.bjp.0704293
更新日期:2001-10-01 00:00:00
abstract::1. 1-3(Chlorophenyl)piperazine (mCPP) (5 mg kg-1, i.p.) inhibited 2 h food intake in rats previously deprived of food for one day. Ten 5-hydroxytryptamine (5-HT) antagonists given s.c. opposed this hypophagic response. Calculated ID50 values correlated significantly with reported affinities (r = 0.81, n = 10, P less t...
journal_title:British journal of pharmacology
pub_type: 杂志文章
doi:10.1111/j.1476-5381.1991.tb12369.x
更新日期:1991-08-01 00:00:00
abstract::1. An investigation into the effects of cholecystokinin octapeptide (CCK-8S) and its pentapeptide analogue, pentagastrin, on neurones located in ventromedial nuclei of rat hypothalamic slices maintained in vitro has been undertaken. 2. CCK-8S (0.01-1.0 microM) applied in the perfusion medium produced a concentration-d...
journal_title:British journal of pharmacology
pub_type: 杂志文章
doi:10.1111/j.1476-5381.1988.tb11521.x
更新日期:1988-05-01 00:00:00
abstract::The effect of adenosine on transepithelial ion transport was investigated in isolated preparations of murine trachea mounted in Ussing chambers. The possible regulation of adenosine receptors in an established model of allergic airway inflammation was also investigated. Mucosally applied adenosine caused increases in ...
journal_title:British journal of pharmacology
pub_type: 杂志文章
doi:10.1038/sj.bjp.0706133
更新日期:2005-04-01 00:00:00
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journal_title:British journal of pharmacology
pub_type: 杂志文章
doi:10.1111/j.1476-5381.1985.tb12936.x
更新日期:1985-02-01 00:00:00
abstract:BACKGROUND AND PURPOSE:Pyrazole derivatives have recently been suggested as selective blockers of transient receptor potential cation (TRPC) channels but their ability to distinguish between the TRPC and Orai pore complexes is ill-defined. This study was designed to characterize a series of pyrazole derivatives in term...
journal_title:British journal of pharmacology
pub_type: 杂志文章
doi:10.1111/j.1476-5381.2012.02126.x
更新日期:2012-12-01 00:00:00
abstract:BACKGROUND AND PURPOSE:Our team previously demonstrated that diabetes induces a deterioration in vascular dynamics, in parallel with the enhanced formation of advanced glycation end products. The aim of this study was to determine whether prevention of the arterial stiffening by pyridoxamine in diabetes is associated w...
journal_title:British journal of pharmacology
pub_type: 杂志文章
doi:10.1111/j.1476-5381.2009.00309.x
更新日期:2009-08-01 00:00:00