Abstract:
:1. The modulation of the gamma-aminobutyric acidA (GABAA) receptor by reduced metabolites of progesterone and deoxycorticosterone has been compared with that produced by depressant barbiturates in: (a) voltage-clamp recordings from bovine enzymatically isolated chromaffin cells in cell culture, and (b) an assay of the specific binding of [3H]-muscimol to a preparation of porcine brain membranes. 2. The progesterone metabolites 5 alpha- and 5 beta-pregnan-3 alpha-ol-20-one (greater than or equal to 30 nM) reversibly and dose-dependently enhanced the amplitude of membrane currents elicited by locally applied GABA (100 microM), and over the concentration range 30 nM-100 microM stimulated the binding of [3H]-muscimol. In contrast, 5 alpha- and 5 beta-pregnan-3 beta-ol-20-one (30 nM-100 microM) had little effect in either assay, indicating a marked stereoselectivity of steroid action. 3. Scatchard analysis of the ligand binding data suggested an apparent increase in the number, rather than the affinity, of detectable [3H]-muscimol binding sites as the principle action of the active steroid isomers. 4. GABA-evoked currents were also potentiated by androsterone (1 microM) and the deoxycorticosterone metabolite 5 alpha-pregnane-3 alpha,21-diol-20-one (100 nM). 5. Secobarbitone (10-100 microM), pentobarbitone (10-300 microM) and phenobarbitone (100-500 microM) reversibly and dose-dependently potentiated the amplitude of GABA-evoked currents in the absence of any change in their reversal potential. 6. At relatively high concentrations (greater than or equal to 30 microM) secobarbitone and pentobarbitone directly elicited a membrane current. It is concluded that such currents result from GABAA receptor-channel activation since they share a common reversal potential with GABA-evoked responses (approximately 0 mV), are reversibly antagonized by bicuculline (3 microM), and potentiated by either diazepam (1 microM) or 5 beta-pregnan-3 alpha-ol-20-one (500 nM). 7. Secobarbitone (1 microM-1 mM) dose-dependently enhanced the binding of [3H]-muscimol. In common with the active steroids, an increase in the apparent number of binding sites was responsible for this effect. 8. A saturating concentration (1 mM) of secobarbitone in the ligand binding assay did not suppress the degree of enhancement of control binding produced by 5 beta-pregnan-3 alpha-ol-20-one (30 nM-100 microM). Similarly the steroid, at a concentration of 100 microM, did not influence the enhancement of [3H]-muscimol binding by secobarbitone (1 microM-1 mM). In all combinations of concentrations tested, the effects of secobarbitone and 5#-pregnan-3a-ol-20-one on [3H]-muscimol binding were additive. 9. In conjunction with previously published observations, the present data indicate close similarities in the GABA-mimetic and potentiating actions of barbiturates and steroids. However, the results obtained with combinations of steroids and barbiturates in the ligand binding assay appear inconsistent with the two classes of compound interacting with a common site to modulate the GABAA receptor activity.
journal_name
Br J Pharmacoljournal_title
British journal of pharmacologyauthors
Peters JA,Kirkness EF,Callachan H,Lambert JJ,Turner AJdoi
10.1111/j.1476-5381.1988.tb11646.xsubject
Has Abstractpub_date
1988-08-01 00:00:00pages
1257-69issue
4eissn
0007-1188issn
1476-5381journal_volume
94pub_type
杂志文章abstract:BACKGROUND AND PURPOSE:Inhibitors of phosphodiesterase 5 (PDE5) affect signalling pathways by elevating cGMP, which is a second messenger involved in processes of neuroplasticity. In the present study, the effects of the PDE5 inhibitor, sildenafil, on the pathological features of Alzheimer's disease and on memory-relat...
journal_title:British journal of pharmacology
pub_type: 杂志文章
doi:10.1111/j.1476-5381.2011.01517.x
更新日期:2011-12-01 00:00:00
abstract::Pulmonary fibrosis represents the end stage of a number of heterogeneous conditions and is, to a greater or lesser degree, the hallmark of the interstitial lung diseases. It is characterized by the excessive deposition of extracellular matrix proteins within the pulmonary interstitium leading to the obliteration of fu...
journal_title:British journal of pharmacology
pub_type: 杂志文章,评审
doi:10.1111/j.1476-5381.2011.01247.x
更新日期:2011-05-01 00:00:00
abstract::1. SCA40 (1nM-10 microM), isoprenaline (1-300 nM) and levcromakalim (100 nM-10 microM) each produced concentration-dependent suppression of the spontaneous tone of guinea-pig isolated trachea. Propranolol (1 microM) markedly (approximately 150 fold) antagonized isoprenaline but did not antagonize SCA40. The tracheal r...
journal_title:British journal of pharmacology
pub_type: 杂志文章
doi:10.1111/j.1476-5381.1995.tb14918.x
更新日期:1995-01-01 00:00:00
abstract::1. In a first series of experiments, male Long Evans rats were chronically instrumented for the measurement of internal carotid blood flow and systemic arterial blood pressure; cardiovascular changes were assessed during and after 30 min infusions of human alpha-calcitonin gene-related peptide (CGRP) (0.06 and 0.6 nmo...
journal_title:British journal of pharmacology
pub_type: 杂志文章
doi:10.1111/j.1476-5381.1990.tb13015.x
更新日期:1990-04-01 00:00:00
abstract::1. Contraction of the rabbit isolated saphenous vein is mediated by a heterogeneous endothelin (ET) receptor population. This study has characterized these receptor subtypes by use of several pharmacologically distinct ET receptor agonists and antagonists. 2. ET-1, ET-3, sarafotoxin S6c (STXc) and [Ala3,11]ET-1 produc...
journal_title:British journal of pharmacology
pub_type: 杂志文章
doi:10.1111/j.1476-5381.1995.tb14936.x
更新日期:1995-04-01 00:00:00
abstract::1. Prostaglandins and the vasodilator neuropeptide, calcitonin-gene related peptide (CGRP), have both been implicated in the pathogenesis of migraine headache. We have used primary cultures of adult rat trigeminal neurones to examine the effects of prostanoids on CGRP release in vitro. 2. CGRP release was stimulated b...
journal_title:British journal of pharmacology
pub_type: 杂志文章
doi:10.1038/sj.bjp.0704357
更新日期:2001-11-01 00:00:00
abstract:BACKGROUND AND PURPOSE:4-[3,5-Bis(2-chlorobenzylidene)-4-oxo-piperidine-1-yl]-4-oxo-2-butenoic acid CLEFMA is a new anti-cancer molecule. Here, we investigated changes in apoptosis and inflammatory markers during CLEFMA-induced tumour suppression. EXPERIMENTAL APPROACH:Lung adenocarcinoma H441 and A549, and normal lun...
journal_title:British journal of pharmacology
pub_type: 杂志文章
doi:10.1111/bph.12406
更新日期:2013-12-01 00:00:00
abstract::The interaction of ketamine with the 5-HT3 receptor of rabbit nodose ganglion neurones is described. Ketamine (3-30 microM) enhanced 5-HT3 receptor-mediated currents recorded under voltage-clamp conditions. This action did not appear to be related to the known effect of ketamine of inhibiting 5-HT uptake. ...
journal_title:British journal of pharmacology
pub_type: 杂志文章
doi:10.1111/j.1476-5381.1991.tb09837.x
更新日期:1991-07-01 00:00:00
abstract::A method is described for the determination of halothane-induced sleeping time in the rat. 2 The sleeping time exhibited a diurnal variation which was due, at least in part, to a change in the sensitivity of the central nervous system (CNS) to the anaesthetic. 3 Tolerance to halothane did not develop in rats repeatedl...
journal_title:British journal of pharmacology
pub_type: 杂志文章
doi:10.1111/j.1476-5381.1976.tb07689.x
更新日期:1976-09-01 00:00:00
abstract::1. Previous patch clamp studies of oesophageal circular muscle cells showed that nitric oxide (NO) modulated the opening of Ca2(+)-activated K+ channels involved in mediating the inhibitory junction potentials (i.j.ps). This study clarified the role of Ca2+ release from the superficial sarcoplasmic reticulum (SR) in t...
journal_title:British journal of pharmacology
pub_type: 杂志文章
doi:10.1111/j.1476-5381.1996.tb15661.x
更新日期:1996-08-01 00:00:00
abstract:BACKGROUND AND PURPOSE:Partial agonists selective for α4β2 nicotinic ACh receptors have been developed for smoking cessation as they induce weak activation of native α4β2* receptors and inhibit effect of nicotine. However, it is unclear whether at brain functions there is an existence of receptor reserve that allows we...
journal_title:British journal of pharmacology
pub_type: 杂志文章
doi:10.1111/j.1476-5381.2011.01628.x
更新日期:2012-02-01 00:00:00
abstract::Chronic itch poses major health care and economic burdens worldwide. In 2013, B-type natriuretic peptide (BNP) was identified as an itch-selective neuropeptide and shown to be both necessary and sufficient to produce itch behaviour in mice. Since then, mechanistic studies of itch have increased, not only at central le...
journal_title:British journal of pharmacology
pub_type: 杂志文章,评审
doi:10.1111/bph.14952
更新日期:2020-03-01 00:00:00
abstract:BACKGROUND AND PURPOSE:Two of the most relevant unmet needs in epilepsy are represented by the development of disease-modifying drugs able to affect epileptogenesis and/or the study of related neuropsychiatric comorbidities. No systematic study has investigated the effects of chronic treatment with antipsychotics or an...
journal_title:British journal of pharmacology
pub_type: 杂志文章
doi:10.1111/bph.13121
更新日期:2015-06-01 00:00:00
abstract:BACKGROUND AND PURPOSE:Although the stoichiometry of the major synaptic αβγ subunit-containing GABAA receptors has consensus support for 2α:2β:1γ, a clear view of the stoichiometry of extrasynaptic receptors containing δ subunits has remained elusive. Here we examine the subunit stoichiometry of recombinant α4β3δ recep...
journal_title:British journal of pharmacology
pub_type: 杂志文章
doi:10.1111/bph.12514
更新日期:2014-02-01 00:00:00
abstract::Since its discovery over 50 years ago, cAMP has been the archetypal second messenger introducing students to the concept of cell signalling at the simplest level. As explored in this review, however, there are many more facets to cAMP signalling than the path from Gs-coupled receptor to adenylyl cyclase (AC) to cAMP t...
journal_title:British journal of pharmacology
pub_type: 杂志文章,评审
doi:10.1111/j.1476-5381.2011.01719.x
更新日期:2012-05-01 00:00:00
abstract::1. It has been reported that activation of beta-adrenoceptors may be responsible for the hyperaemic response of the hepatic artery to portal venous blood flow reduction. 2. The effect of beta-adrenoceptor blockade on the hepatic arterial response to portal vein occlusion was investigated in 6 anaesthetized dogs. A sid...
journal_title:British journal of pharmacology
pub_type: 杂志文章
doi:10.1111/j.1476-5381.1989.tb11825.x
更新日期:1989-02-01 00:00:00
abstract::1. We previously showed that chronic exposure to aspirin (100 mg kg-1 daily, by mouth) is effective in preventing the onset of hypertension in young (28-84 day old) spontaneously hypertensive rats (SHRs). This is contrary to what others have reported using older SHRs. 2. Renal prostaglandin F2 alpha was also reduced i...
journal_title:British journal of pharmacology
pub_type: 杂志文章
doi:10.1111/j.1476-5381.1988.tb11585.x
更新日期:1988-07-01 00:00:00
abstract:BACKGROUND AND PURPOSE:Nitric oxide (NO) is known to activate NO-sensitive guanylyl cyclase (NO-GC) and to elicit cGMP production. However, NO has also been proposed to induce cGMP-independent effects. It is accepted practice to use specific NO-GC inhibitors, such as ODQ or NS2028, to assess cGMP-dependent NO effects. ...
journal_title:British journal of pharmacology
pub_type: 杂志文章
doi:10.1111/bph.12275
更新日期:2013-09-01 00:00:00
abstract::1. The effects of the lipoxygenase inhibitor nordihydroguaiaretic acid (NDGA) on the ionic currents of rat carotid body type I cells were investigated by use of whole-cell and outside-out patch clamp techniques. 2. NDGA (5-50 microM) produced a concentration-dependent inhibition of whole-cell K+ currents at all activa...
journal_title:British journal of pharmacology
pub_type: 杂志文章
doi:10.1038/sj.bjp.0701452
更新日期:1997-11-01 00:00:00
abstract::1. The presence of an endogenous digitalis-like factor (EDLF) in the plasma of both normal and volume expanded animals is well documented. In this study we have used ouabain and bufalin as pharmacological analogues to mimic the renal effects of EDLF and to investigate whether any interaction occurs between atrial natr...
journal_title:British journal of pharmacology
pub_type: 杂志文章
doi:10.1111/j.1476-5381.1993.tb12852.x
更新日期:1993-03-01 00:00:00
abstract:BACKGROUND AND PURPOSE:11β-hydroxysteroid dehydrogenase type I (11β-HSD1), a target for Type 2 diabetes mellitus, converts inactive glucocorticoids into bioactive forms, increasing tissue concentrations. We have compared the pharmacokinetic-pharmacodynamic (PK/PD) relationship of target inhibition after acute and repea...
journal_title:British journal of pharmacology
pub_type: 杂志文章
doi:10.1111/bph.13251
更新日期:2015-10-01 00:00:00
abstract::1 The effects of indomethacin and eicosa-5,8,11,14-tetraynoic acid (ETYA) on the contractile response of the transmurally stimulated rabbit portal vein were studied in vitro.2 When the veins were stimulated for 240 pulses at 1 and 2 Hz, the responses were potentiated by indomethacin and ETYA. However, responses to 4 a...
journal_title:British journal of pharmacology
pub_type: 杂志文章
doi:10.1111/j.1476-5381.1974.tb09687.x
更新日期:1974-09-01 00:00:00
abstract:BACKGROUND AND PURPOSE:Tooth eruption is a complicated process regulated by the dental follicles (DF). Our recent study discovered that tooth eruption was inhibited upon injection of bleomycin into DF. However, the mechanisms were unknown. EXPERIMENTAL APPROACH:Human dental follicle cells (hDFCs) were treated by bleom...
journal_title:British journal of pharmacology
pub_type: 杂志文章
doi:10.1111/bph.15281
更新日期:2020-10-17 00:00:00
abstract::G protein-coupled receptors are the largest group of membrane proteins and are the targets for approximately 30% of drugs currently used therapeutically. These 7-transmembrane-spanning proteins continue to provide new opportunities to develop therapeutics based on emerging knowledge of their structure, signalling prop...
journal_title:British journal of pharmacology
pub_type: 社论
doi:10.1111/j.1476-5381.2010.00695.x
更新日期:2010-03-01 00:00:00
abstract::1. N(G)-monomethyl-L-arginine (L-NMMA) constricts human forearm resistance vasculature and selectively attenuates vasodilator responses to endothelium-dependent vasodilators. Incomplete inhibition of such responses could be due to an inadequate dose of L-NMMA or to NO-independent vasodilator mechanisms. 2. This study ...
journal_title:British journal of pharmacology
pub_type: 临床试验,杂志文章
doi:10.1038/sj.bjp.0704338
更新日期:2001-11-01 00:00:00
abstract:BACKGROUND AND PURPOSE:While arachidonyl ethanolamine (anandamide) produces pharmacological effects mediated by cannabinoid CB1 receptors, it is also an agonist at the transient receptor potential vanilloid type 1 (TRPV1) ion channel. This study examined the cellular actions of anandamide in the midbrain periaqueductal...
journal_title:British journal of pharmacology
pub_type: 杂志文章
doi:10.1111/j.1476-5381.2010.01157.x
更新日期:2011-07-01 00:00:00
abstract::1 Burimamide injected intravenously in the anaesthetized or conscious cat produced significant increases in gastric acid secretion: in the anaesthetized cat it produced increased gastric mucosal blood flow. 2 Metiamide, in doses which inhibited pentagastrin-stimulated acid secretion, produced no increase in gastric ac...
journal_title:British journal of pharmacology
pub_type: 杂志文章
doi:10.1111/j.1476-5381.1975.tb07361.x
更新日期:1975-02-01 00:00:00
abstract::1. Stimulation of the murine macrophage cell line RAW 264.7 with thapsigargin, an endomembrane Ca(2+)-ATPase inhibitor, induced histamine production in a time- and concentration-dependent manner. 2. The protein kinase C activator, 12-O-tetradecanoylphorbol 13-acetate (TPA), also enhanced histamine production. 3. alpha...
journal_title:British journal of pharmacology
pub_type: 杂志文章
doi:10.1038/sj.bjp.0703085
更新日期:2000-02-01 00:00:00
abstract::1 Adenosine, adenosine monophosphate and adenosine triphosphate (ATP) depressed the firing rate of neurones in the rat cerebral cortex when applied by microinontophoresis. 2 4-Aminopyridine, also applied iontophoretically blocked the depressant effects of the purines, without affecting responses to gamma-aminobutyric ...
journal_title:British journal of pharmacology
pub_type: 杂志文章
doi:10.1111/j.1476-5381.1980.tb08720.x
更新日期:1980-11-01 00:00:00
abstract::1. We have investigated the inhibitory effects of RP 73401 (piclamilast) and rolipram against human monocyte cyclic AMP-specific phosphodiesterase (PDE4) in relation to their effects on prostaglandin (PG)E2-induced cyclic AMP accumulation and lipopolysaccharide (LPS)-induced TNF alpha production and TNF alpha mRNA exp...
journal_title:British journal of pharmacology
pub_type: 杂志文章
doi:10.1111/j.1476-5381.1996.tb15450.x
更新日期:1996-06-01 00:00:00