Abstract:
:The modulation of the gamma-aminobutyric acidA (GABAA) receptor by alphaxalone has been investigated by use of voltage-clamp recordings from enzymatically isolated bovine chromaffin cells maintained in cell culture. Alphaxalone (greater than 30 nM) reversibly and dose-dependently potentiated the amplitude of membrane currents elicited by locally applied GABA (100 microM). The potentiation was not associated with a change in the reversal potential of GABA-evoked currents and was not influenced by the benzodiazepine receptor antagonist, Ro15-1788 (300 nM). At relatively high concentrations (greater than 1 microM), alphaxalone directly elicited a membrane current. It is concluded that such currents result from GABAA receptor activation since they were reversibly suppressed by bicuculline (3 microM), dose-dependently enhanced by phenobarbitone (100-500 microM), and had a similar reversal potential (approximately 0 mV) to currents elicited by GABA. Additionally, on outside-out membrane patches, alphaxalone activated single channel currents with amplitudes and a reversal potential similar to those evoked by GABA. Alphaxalone (30 nM-1 microM) had no effect upon the amplitude of membrane currents elicited by locally applied acetylcholine (ACh) (100 microM). However, higher concentrations of alphaxalone (10-100 microM) reversibly suppressed ACh-evoked currents, the IC50 for blockade being 20 microM. The beta-hydroxy isomer of alphaxalone, betaxalone (100 nM-1 microM), did not potentiate GABA-induced currents, nor did higher concentrations of the steroid (10-100 microM) directly evoke a membrane current. However, over the latter concentration range, betaxalone suppressed the amplitude of currents elicited either by GABA or ACh. The relevance of the present results to the anaesthetic action of alphaxalone is discussed together with the broader implications of steroidal modulation of the GABAA receptor.
journal_name
Br J Pharmacoljournal_title
British journal of pharmacologyauthors
Cottrell GA,Lambert JJ,Peters JAdoi
10.1111/j.1476-5381.1987.tb11198.xsubject
Has Abstractpub_date
1987-03-01 00:00:00pages
491-500issue
3eissn
0007-1188issn
1476-5381journal_volume
90pub_type
杂志文章abstract::The variety of factors and events involved in neurodegeneration renders the subject a major challenge. Neurodegenerative disorders include a number of different pathological conditions, which share similar critical metabolic processes, such as protein aggregation and oxidative stress, both of which are associated with...
journal_title:British journal of pharmacology
pub_type: 杂志文章,评审
doi:10.1038/sj.bjp.0706416
更新日期:2005-12-01 00:00:00
abstract::1 In cats anaesthetized with pentobarbitone and vagotomized, observations were made on the phrenic nerve action potential and the diaphragm electromyogram (EMG) at constant end-tidal Pco(2). Arterial blood pressure was stabilized by intravenous infusions of noradrenaline.2 Intravenous administration of saxitoxin (STX)...
journal_title:British journal of pharmacology
pub_type: 杂志文章
doi:10.1111/j.1476-5381.1980.tb10419.x
更新日期:1980-02-01 00:00:00
abstract::1. Gastric acid secretory responses to pentagastrin were characterized in the rat isolated gastric mucosa. In particular, the mechanisms underlying fade, declining response upon continued stimulation, and tachyphylaxis, progressively reduced responses upon repeated stimulation, were investigated. 2. Pentagastrin, 10(-...
journal_title:British journal of pharmacology
pub_type: 杂志文章
doi:10.1111/j.1476-5381.1988.tb11738.x
更新日期:1988-12-01 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
abstract::The effects of 5-hydroxytryptamine (5-HT) on the release of gamma-aminobutyric acid (GABA) were examined in the longitudinal muscle-myenteric plexus (LM-MP) preparation of guinea-pig ileum. 5-HT increased the spontaneous release and inhibited the electrically-evoked release of [3H]-GABA. The 5-HT-evoked release was Ca...
journal_title:British journal of pharmacology
pub_type: 杂志文章
doi:10.1111/j.1476-5381.1989.tb12601.x
更新日期:1989-10-01 00:00:00
abstract::1. In rat aortic rings contracted by phenylephrine, the relaxation induced by isoprenaline was partly inhibited by iberiotoxin, (ibTX), tetraethylammonium, 4-aminopyridine (4-AP) and 1,9-dideoxyforskolin, but not by glibenclamide. 2. In the presence of 4-AP, 1,9-dideoxyforskolin failed to inhibit further the relaxant ...
journal_title:British journal of pharmacology
pub_type: 杂志文章
doi:10.1111/j.1476-5381.1996.tb15700.x
更新日期:1996-10-01 00:00:00
abstract::1. It was postulated that swelling dependent chloride channels are involved in the proton secretion of parietal cells. Since omeprazole, lansoprazole and its acid activated sulphenamide form AG2000 are structurally related to phenol derivatives known to block swelling dependent chloride channels, we set out to test, w...
journal_title:British journal of pharmacology
pub_type: 杂志文章
doi:10.1038/sj.bjp.0703070
更新日期:2000-02-01 00:00:00
abstract::British Journal of Pharmacology (BJP) is pleased to publish a new set of guidelines for reporting research involving animals, simultaneously with several other journals; the 'ARRIVE' guidelines (Animals in Research: Reporting In Vivo Experiments). This editorial summarizes the background to the guidelines, gives our v...
journal_title:British journal of pharmacology
pub_type: 社论
doi:10.1111/j.1476-5381.2010.00873.x
更新日期:2010-08-01 00:00:00
abstract:BACKGROUND AND PURPOSE:Chemokines and their receptors form an intricate interaction and signalling network that plays critical roles in various physiological and pathological cellular processes. The high promiscuity and apparent redundancy of this network makes probing individual chemokine/receptor interactions and fun...
journal_title:British journal of pharmacology
pub_type: 杂志文章
doi:10.1111/bph.14132
更新日期:2018-05-01 00:00:00
abstract::1. The pharmacokinetics of cyclophosphamide were investigated in cancer patients. The data can be characterized by a two-compartment open model. The half life of the elimination phase of the drug ranged between 3 and 11 hours.2. Extensive tubular reabsorption of the drug resulted in the excretion of only a small perce...
journal_title:British journal of pharmacology
pub_type: 杂志文章
doi:10.1111/j.1476-5381.1971.tb07199.x
更新日期:1971-11-01 00:00:00
abstract::Burimamide, an H(2)-receptor blocking agent, has been shown capable of blocking the uptake and metabolism of [(14)C]-histamine, both in the guinea-pig isolated atrium and in murine neoplastic mast cells. This occurs even at concentrations far below the dose range capable of blocking the positive chronotropic effect of...
journal_title:British journal of pharmacology
pub_type: 杂志文章
doi:10.1111/j.1476-5381.1973.tb08384.x
更新日期:1973-10-01 00:00:00
abstract::1. We studied the effects of flash photolysis on the novel enantiomeric cardiac inotropes EMD 57033 (a calcium sensitizer) and EMD 57439 (a phosphodiesterase III inhibitor) in rat isolated ventricular trabeculae. 2. In skinned trabeculae, EMD 57439 had no effect on force production, consistent with lack of an active c...
journal_title:British journal of pharmacology
pub_type: 杂志文章
doi:10.1111/j.1476-5381.1996.tb15641.x
更新日期:1996-08-01 00:00:00
abstract::1. Intracerebral microdialysis was used to examine the function of the terminal 5-hydroxytryptamine (5-HT) autoreceptor in the anterior hypothalamus of anaesthetized rats at two points in the light phase of the light-dark cycle. 2. Infusion of the 5-HT1A/1B agonist 5-methoxy-3-(1,2,3,6-tetrahydro-4-pyridyl)-1H-indole ...
journal_title:British journal of pharmacology
pub_type: 杂志文章
doi:10.1038/sj.bjp.0702535
更新日期:1999-04-01 00:00:00
abstract:BACKGROUND AND PURPOSE:A fluorinated derivative (2F-MT-45) of the synthetic μ-opioid receptor agonist MT-45 (1-cyclohexyl-4-(1,2-diphenylethyl)piperazine) was recently identified in a seized illicit tablet. While MT-45 is a Class A drug, banned in a number of countries, nothing is known about the pharmacology of 2F-MT-...
journal_title:British journal of pharmacology
pub_type: 杂志文章
doi:10.1111/bph.15064
更新日期:2020-08-01 00:00:00
abstract::Halothane has many effects on the resting membrane potential (V(m)) of excitable cells and exerts numerous effects on skeletal muscle one of which is the enhancement of Ca(2+) release by the sarcoplasmic reticulum (SR) resulting in a sustained contracture. The aim of this study was to analyse the effects of clinical d...
journal_title:British journal of pharmacology
pub_type: 杂志文章
doi:10.1038/sj.bjp.0703330
更新日期:2000-06-01 00:00:00
abstract::1. The aim of this study was to assess the role of endothelial cells in the modulation of vasocontractile responses to endothelin-1 (ET-1) of human placental vasculature. 2. Isolated stem villi small arteries (diameter = 170-250 microns) were obtained from healthy parturients who underwent caesarean surgery during the...
journal_title:British journal of pharmacology
pub_type: 杂志文章
doi:10.1111/j.1476-5381.1995.tb15915.x
更新日期:1995-07-01 00:00:00
abstract:BACKGROUND AND PURPOSE:Endocannabinoids play an important role in modulating spinal nociceptive signalling, crucial for the development of pain. The cannabinoid CB1 receptor and the TRPV1 cation channel are both activated by the endocannabinoid anandamide, a product of biosynthesis from the endogenous lipid precursor N...
journal_title:British journal of pharmacology
pub_type: 杂志文章
doi:10.1111/bph.13849
更新日期:2018-06-01 00:00:00
abstract::1. Inositol phospholipid hydrolysis was examined in human cerebral cortex slices by a [3H]-inositol prelabelling assay. 2. Enhancement of [3H]-inositol phosphates accumulation was observed in the presence of carbachol, noradrenaline, histamine, 5-hydroxytryptamine (5-HT) and depolarizing concentrations of KCl. 3. Desp...
journal_title:British journal of pharmacology
pub_type: 杂志文章
doi:10.1111/j.1476-5381.1990.tb12048.x
更新日期:1990-05-01 00:00:00
abstract::1. This study compares a cyclo-oxygenase inhibitor (aspirin), a 5-HT2 antagonist (ZM170809) and a combined thromboxane synthase inhibitor/receptor antagonist (ZD1542) as adjuncts to tissue plasminogen activator (rt-PA). 2. Application of an anodal current (332 +/- 4.1 microA) to the stenosed left circumflex coronary a...
journal_title:British journal of pharmacology
pub_type: 杂志文章
doi:10.1111/j.1476-5381.1994.tb13063.x
更新日期:1994-05-01 00:00:00
abstract::1. Selective antagonism of the cardiac beta(1)-adrenoceptors has been studied in normal human volunteers.2. Practolol and UK 6558 produced greater antagonism of the chronotropic and inotropic responses to i.v. isoprenaline than of the vasodilator response to either i.v. or intra-arterial isoprenaline. A third drug, M&...
journal_title:British journal of pharmacology
pub_type: 杂志文章
doi:10.1111/j.1476-5381.1973.tb08272.x
更新日期:1973-09-01 00:00:00
abstract::There is evidence that cannabinoid-based medicines that are selective for different targets in the cannabinoid signalling system (e.g. receptors, inactivation mechanism, enzymes) might be beneficial in basal ganglia disorders, namely Parkinson's disease (PD) and Huntington's disease (HD). These benefits not only inclu...
journal_title:British journal of pharmacology
pub_type: 杂志文章,评审
doi:10.1111/j.1476-5381.2008.00088.x
更新日期:2009-04-01 00:00:00
abstract:BACKGROUND AND PURPOSE:Up-regulation of thioredoxin interacting protein (TXNIP), an endogenous inhibitor of thioredoxin (Trx), compromises cellular antioxidant and anti-apoptotic defences and stimulates pro-inflammatory cytokines expression, implying a role for TXNIP in apoptosis. Here we have examined the causal role ...
journal_title:British journal of pharmacology
pub_type: 杂志文章
doi:10.1111/j.1476-5381.2011.01336.x
更新日期:2011-09-01 00:00:00
abstract::1. The present study was designed to characterize the positive inotropic response to DPI 201-106 in isolated papillary muscle strips obtained from heart failure patients undergoing surgery. 2. The positive inotropic responses to isoprenaline and milrinone and cardiac beta-adrenoceptor density were also determined. 3. ...
journal_title:British journal of pharmacology
pub_type: 杂志文章
doi:10.1111/j.1476-5381.1989.tb16892.x
更新日期:1989-09-01 00:00:00
abstract::Hind paw oedema in rats, measured by plethysmography or extravasation of Evans Blue dye into the skin, after subplantar injection of submaximal doses of carrageenin (1-100 micrograms) was significantly increased for 4 h during kininase II inhibition with captopril (1 mg kg-1, s.c.). Submaximal oedema, as assessed by p...
journal_title:British journal of pharmacology
pub_type: 杂志文章
doi:10.1111/j.1476-5381.1984.tb16435.x
更新日期:1984-05-01 00:00:00
abstract::The Wnt/β-catenin signalling pathway is pivotal for stem cell function and the control of cellular differentiation, both during embryonic development and tissue homeostasis in adults. Its activity is carefully controlled through the concerted interactions of concentration-limited pathway components and a wide range of...
journal_title:British journal of pharmacology
pub_type: 杂志文章,评审
doi:10.1111/bph.14038
更新日期:2017-12-01 00:00:00
abstract::1. The effects of adrenaline, noradrenaline, isoprenaline and terbutaline (PINN), 1-(3,5-dihydroxyphenyl)-2(t-butylamino)-ethanol, on the sphincter of Oddi were studied in anaesthetized cats. Both adrenaline and noradrenaline (1-4 mug/kg) increased resistance to flow through the sphincter. This effect was blocked by d...
journal_title:British journal of pharmacology
pub_type: 杂志文章
doi:10.1111/j.1476-5381.1970.tb10369.x
更新日期:1970-07-01 00:00:00
abstract::1. The present study was designed to test the hypothesis that beneficial effects of angiotensin converting enzyme (ACE)inhibitors are independent of a fall in blood pressure in rat experimental heart failure following coronary ligation. 2. The animals were assigned randomly to six groups; sham operation, controls subj...
journal_title:British journal of pharmacology
pub_type: 杂志文章
doi:10.1111/j.1476-5381.1994.tb13155.x
更新日期:1994-07-01 00:00:00
abstract::1. Recent studies demonstrated that the cardiac calpain system is activated during ischaemic events and is involved in cardiomyocyte injury. The aim of this study was to investigate the contribution of AT(1) and AT(2) receptors in the regulation of calpain-mediated myocardial damage following myocardial infarction (MI...
journal_title:British journal of pharmacology
pub_type: 杂志文章
doi:10.1038/sj.bjp.0703860
更新日期:2001-02-01 00:00:00
abstract::Heart disease is a major cause of morbidity and mortality throughout the world. Some cardiovascular conditions can be modulated by lifestyle factors such as increased exercise or a healthier diet, but many require surgical or pharmacological interventions for their management. More targeted and less invasive therapies...
journal_title:British journal of pharmacology
pub_type: 杂志文章,评审
doi:10.1111/bph.13678
更新日期:2017-10-01 00:00:00
abstract:BACKGROUND AND PURPOSE:SU4312, a potent and selective inhibitor of VEGF receptor-2 (VEGFR-2), has been designed to treat cancer. Recent studies have suggested that SU4312 can also be useful in treating neurodegenerative disorders. In this study, we assessed neuroprotection by SU4312 against 1-methyl-4-phenylpyridinium ...
journal_title:British journal of pharmacology
pub_type: 杂志文章
doi:10.1111/bph.12004
更新日期:2013-03-01 00:00:00