Abstract:
:1. Simultaneous computer modelling of control and guanfacine-masked [3H]-MK 912 saturation curves as well as guanfacine competition curves revealed that the drugs bound to two alpha 2-adrenoceptor subtypes in the rat cerebral cortex with very different selectivities. These alpha 2-adrenoceptor subtypes were designated alpha 2A and alpha 2C. The Kd value of [3H]-MK 912 for the alpha 2A-subtype was 1.77 nM and for the alpha 2C-subtype 0.075 nM; the receptor sites showing capacities 296 and 33 fmol mg-1 protein, respectively. The Kds of guanfacine were 19.9 and 344 nM, respectively. 2. Binding constants of 26 compounds for the two rat cerebral cortex alpha 2-adrenoceptor subtypes were determined by simultaneous computer modelling of control and guanfacine-masked drug competition curves as well as plain guanfacine competition curves using [3H]-MK912 as labelled ligand (i.e. a '3-curve assay'). Of the tested drugs WB4101, corynanthine, rauwolscine, yohimbine, ARC 239 and prazosin were found to be clearly alpha 2C-selective with selectivities ranging from 16 to 30 fold whereas guanfacine, oxymetazoline, BRL 44408 and BRL 41992 were found to be alpha 2A-selective with selectivities ranging from 9 to 22 fold. 3. The Kds of compounds obtained for the cerebral cortex alpha 2C-adrenoceptors showed an almost 1:1 correlation with the corresponding Kds for alpha 2-adrenoceptors expressed by the pA2d-gene (the rat 'alpha 2-C4' adrenoceptor) in CHO-cells. The cerebral cortex alpha 2A-adrenoceptors did not correlate well with the pA2d alpha 2-adrenoceptor Kds. 4. In the rat spinal cord [3H]-MK 912 bound to alpha 2A- and alpha 2C-adrenoceptor sites with similar affinities as in the cerebral cortex and with densities 172 and 7.4 fmol mg-1 protein, respectively. Drug affinities for some compounds showing major selectivity for alpha 2A- and alpha 2C-adrenoceptors were fully compatible with the notion that the spinal cord sites were alpha 2A- and alpha 2C-adrenoceptors.
journal_name
Br J Pharmacoljournal_title
British journal of pharmacologyauthors
Uhlén S,Xia Y,Chhajlani V,Felder CC,Wikberg JEdoi
10.1111/j.1476-5381.1992.tb14446.xsubject
Has Abstractpub_date
1992-08-01 00:00:00pages
986-95issue
4eissn
0007-1188issn
1476-5381journal_volume
106pub_type
杂志文章abstract::1 The effects of alpha- and beta-adrenoceptor stimulants on the histamine-forming capacity (HFC) of human isolated leucocytes have been studied, in vitro.2 It was confirmed that antigen significantly stimulates the HFC of human leucocytes.3 beta-Adrenoceptor stimulants, such as isoprenaline and salbutamol (10(-6)-10(-...
journal_title:British journal of pharmacology
pub_type: 杂志文章
doi:10.1111/j.1476-5381.1974.tb09702.x
更新日期:1974-10-01 00:00:00
abstract::In vitro preparations of rabbit heart were made from which measurements of effective refractory period (ERP), atrio-Hisian (A-H) and His-Purkinje (H-P) conduction times could be obtained, analogous to electrophysiological measurements customarily carried out in vivo. Intracellular potentials also were recorded from th...
journal_title:British journal of pharmacology
pub_type: 杂志文章
doi:10.1111/j.1476-5381.1983.tb10007.x
更新日期:1983-07-01 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::In ring preparations of the rabbit external jugular vein contracted with the thromboxane-mimetic U-46619, submicromolar concentrations of 5-hydroxytryptamine (5-HT) and chemically related analogues produced relaxations that were dependent on the integrity of the vascular endothelium. The receptor mediating endothelium...
journal_title:British journal of pharmacology
pub_type: 杂志文章
doi:10.1111/j.1476-5381.1987.tb10287.x
更新日期:1987-06-01 00:00:00
abstract::1. Repeated allergen challenge has been shown to increase the role of Rho-kinase in airway smooth muscle (ASM) contraction. We considered the possibility that active allergic sensitization by itself, that is, without subsequent allergen exposure, could be sufficient to enhance Rho-kinase-mediated ASM contraction. 2. G...
journal_title:British journal of pharmacology
pub_type: 杂志文章
doi:10.1038/sj.bjp.0705903
更新日期:2004-10-01 00:00:00
abstract::1 We have investigated the effects of loperamide on intracellular Ca(2+) stores and membrane K(+) channels in insulin-secreting hamster insulinoma (HIT-T15) cells. 2 In cell-attached patch-clamp mode, loperamide (3-250 micro M) activated large single-channel currents. The loperamide-activated currents were tentatively...
journal_title:British journal of pharmacology
pub_type: 杂志文章
doi:10.1038/sj.bjp.0705263
更新日期:2003-05-01 00:00:00
abstract::1 Ca(2+)-activated Cl(-) currents (I(Cl(Ca))) evoked by K(+)-free pipette solutions containing 500 nM Ca(2+) were recorded in rabbit pulmonary artery smooth muscle cells. A voltage step protocol in which the cells were stepped to +70 mV and then to -80 mV produced outward and inward Cl(-) currents respectively that ex...
journal_title:British journal of pharmacology
pub_type: 杂志文章
doi:10.1038/sj.bjp.0705000
更新日期:2003-01-01 00:00:00
abstract:BACKGROUND AND PURPOSE:The non-nucleoside analogue reverse transcriptase inhibitor efavirenz is associated with hepatic toxicity and metabolic disturbances. Although the mechanisms involved are not clear, recent evidence has pinpointed a specific mitochondrial action of efavirenz accompanied by the induction of an endo...
journal_title:British journal of pharmacology
pub_type: 杂志文章
doi:10.1111/bph.13018
更新日期:2015-04-01 00:00:00
abstract::1 Both phasic and tonic responses to KCl 160 mM were reduced by Ca2+ deprivation. After 90 min, the phasic response was abolished but 13 +/- 1.5% of the tonic response remained. This resistant component was still present if the Ca2+-free solution contained EGTA 0.1 mM. The tonic response was more resistant to deprivat...
journal_title:British journal of pharmacology
pub_type: 杂志文章
doi:10.1111/j.1476-5381.1982.tb09195.x
更新日期:1982-05-01 00:00:00
abstract::1. The tachykinin receptor mediating contraction of the guinea-pig isolated proximal urethra has been characterized by use of receptor selective agonists and antagonists. All experiments were performed in the presence of peptidase inhibitors (bestatin, captopril and thiorphan, 1 microM each) in order to reduce peptide...
journal_title:British journal of pharmacology
pub_type: 杂志文章
doi:10.1111/j.1476-5381.1992.tb14430.x
更新日期:1992-08-01 00:00:00
abstract::The ability of chemically detoxified E. coli endotoxins and membrane-active agents to modify the toxicity of native E. coli endotoxin in vivo was examined. The time- and dose-dependent increase in plasma acid phosphatase activity following toxin administration to rats provided a convenient quantitative measure of in v...
journal_title:British journal of pharmacology
pub_type: 杂志文章
doi:10.1111/j.1476-5381.1983.tb11015.x
更新日期:1983-06-01 00:00:00
abstract::Serotonin 5-HT(7) receptors are present in astrocytes. Understanding their role in this type of cell would greatly benefit from the identification of astroglial cell lines expressing this receptor type. The aim of the present study was to assess the expression of native 5-HT(7) receptors and 5-HT(7) receptor mRNA in a...
journal_title:British journal of pharmacology
pub_type: 杂志文章
doi:10.1038/sj.bjp.0705936
更新日期:2004-10-01 00:00:00
abstract::1. The effectiveness of alpha 1- and alpha 2-adrenoceptor activation was compared at different levels of the saphenous and cephalic vein of the dog in vitro. 2. Helically cut strips were used to determine concentration-response curves to phenylephrine, noradrenaline, UK-14,304 (5-bromo-6-(imidazoline-2-ylamino)-quinox...
journal_title:British journal of pharmacology
pub_type: 杂志文章
doi:10.1111/j.1476-5381.1990.tb12719.x
更新日期:1990-10-01 00:00:00
abstract::1. The action of angiotensin on the circular and longitudinal muscle of the human colon has been studied in vitro. The ED50 value (g/ml) of circular muscle was 8.7 x 10(-8) and of longitudinal muscle 3.1 x 10(-8), while the corresponding figures for acetylcholine were 1.6 x 10(-6) and 1.1 x 10(-6), respectively. Angio...
journal_title:British journal of pharmacology
pub_type: 杂志文章
doi:10.1111/j.1476-5381.1970.tb09553.x
更新日期:1970-05-01 00:00:00
abstract::1. The effects of some drugs known to inhibit transmission in the superior cervical ganglion and at the neuromuscular junction were investigated on the cholinergic nerve-smooth muscle junction, using the rat isolated innervated urinary bladder preparation.2. HC-3 and Win 4981 inhibited the indirectly evoked contractio...
journal_title:British journal of pharmacology
pub_type: 杂志文章
doi:10.1111/j.1476-5381.1970.tb09900.x
更新日期:1970-08-01 00:00:00
abstract::1 Plasma noradrenaline concentrations were similar in rats following unilateral renal arterial constriction (two kidney Goldblatt model) and in sham-operated control rats. 2 The development of hypertension was not affected by pretreatment with intracisternal injections of 6-hydroxydopamine. 3 These data suggest that s...
journal_title:British journal of pharmacology
pub_type: 杂志文章
doi:10.1111/j.1476-5381.1977.tb08406.x
更新日期:1977-10-01 00:00:00
abstract::1. The interactions between N-methyl-D-aspartate (NMDA) and metabotropic glutamate receptors (mGluRs) were investigated in striatal slices, by utilizing intracellular recordings, both in current- and voltage-clamp mode. 2. Bath-application (50 microM) or focal application of NMDA induced a transient membrane depolariz...
journal_title:British journal of pharmacology
pub_type: 杂志文章
doi:10.1038/sj.bjp.0700999
更新日期:1997-03-01 00:00:00
abstract::1. The purpose of this study was to determine the in vivo inhibitory efficacy of azapropazone on neutrophil migration. The effects of azapropazone given at a dose of 100 mg kg-1 i.v. every 2 h on the neutrophil migration into skin inflammation sites (blister fluid) as well as into an autologous serum (+/- chemoattract...
journal_title:British journal of pharmacology
pub_type: 杂志文章
doi:10.1111/j.1476-5381.1990.tb14686.x
更新日期:1990-02-01 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:Leucocyte infiltration is a rate-limiting step in the pathophysiology of acute pancreatitis (AP) although the adhesive mechanisms supporting leucocyte-endothelium interactions in the pancreas remain elusive. The aim of this study was to define the role of lymphocyte function antigen-1 (LFA-1) in ...
journal_title:British journal of pharmacology
pub_type: 杂志文章
doi:10.1111/j.1476-5381.2011.01225.x
更新日期:2011-05-01 00:00:00
abstract::1. The effects of inhibiting endogenous nitric oxide (NO) synthesis with NG-monomethyl-L-arginine (L-NMMA) on the systemic and splanchnic circulation have been investigated in rats with experimental chronic portal hypertension, anaesthetized with ketamine. 2. Portal hypertension was induced by partial portal vein liga...
journal_title:British journal of pharmacology
pub_type: 杂志文章
doi:10.1111/j.1476-5381.1992.tb14233.x
更新日期:1992-01-01 00:00:00
abstract::1. We examined the gastric mucosal blood flow (GMBF) and ulcerogenic responses following barrier disruption induced by sodium taurocholate (TC) in diabetic rats and investigated the role of capsaicin-sensitive sensory neurons in these responses. 2. Animals were injected streptozotocin (STZ: 70 mg kg(-1), i.p.) and use...
journal_title:British journal of pharmacology
pub_type: 杂志文章
doi:10.1038/sj.bjp.0701974
更新日期:1998-08-01 00:00:00
abstract::1. Caerulein displayed a potent stimulant action on pancreatic secretion in the dog. Threshold doses were 1-5 ng/kg by rapid intravenous injection, 0.25-1 ng/kg per min by intravenous infusion and 50-100 ng/kg by subcutaneous injection. There was a conspicuous increase not only in the volume flow of pancreatic juice b...
journal_title:British journal of pharmacology
pub_type: 杂志文章
doi:10.1111/j.1476-5381.1969.tb09537.x
更新日期:1969-09-01 00:00:00
abstract::1. Inhibition of mechanical activity in longitudinal muscle strips of rabbit duodenum was induced by perivascular and intramural nerve stimulation.2. The effects of perivascular stimulation were abolished by phentolamine + propranolol, guanethidine, reserpine and by tetrodotoxin. The effects of intramural stimulation ...
journal_title:British journal of pharmacology
pub_type: 杂志文章
doi:10.1111/j.1476-5381.1973.tb06916.x
更新日期:1973-06-01 00:00:00
abstract::1. In the presence of atropine, mepyramine and ranitidine, electric field stimulation of the guinea-pig isolated ileum longitudinal muscle-myenteric plexus preparation resulted in a two component non-adrenergic non-cholinergic contraction. The initial contraction had a duration of approximately 1 s whereas the second ...
journal_title:British journal of pharmacology
pub_type: 杂志文章
doi:10.1111/j.1476-5381.1992.tb09036.x
更新日期:1992-03-01 00:00:00
abstract::1. The mechanisms involved in tachykinin-induced oedema were investigated in rat skin and interactions between the tachykinins and calcitonin gene-related peptide (CGRP) were studied. 2. Intradermal injections of the tachykinins, substance P, neurokinin A and neurokinin B, stimulated local oedema formation which was i...
journal_title:British journal of pharmacology
pub_type: 杂志文章
doi:10.1111/j.1476-5381.1989.tb11926.x
更新日期:1989-05-01 00:00:00
abstract:BACKGROUND AND PURPOSE:beta-Amyloid peptide (Abeta) is implicated in the pathogenesis of Alzheimer's disease by initiating a cascade of events from mitochondrial dysfunction to neuronal death. The metabolic enhancer piracetam has been shown to improve mitochondrial dysfunction following brain aging and experimentally i...
journal_title:British journal of pharmacology
pub_type: 杂志文章
doi:10.1111/j.1476-5381.2010.00656.x
更新日期:2010-05-01 00:00:00
abstract:BACKGROUND AND PURPOSE:Cloxyquin (5-cloroquinolin-8-ol) has been described as an activator of TRESK (K2P 18.1, TWIK-related spinal cord K+ channel) background potassium channel. We have examined the specificity of the drug by testing several K2P channels. We have investigated the mechanism of cloxyquin-mediated TRESK a...
journal_title:British journal of pharmacology
pub_type: 杂志文章
doi:10.1111/bph.13821
更新日期:2017-07-01 00:00:00
abstract:BACKGROUND AND PURPOSE:We previously demonstrated that chronic hyperinsulinaemia induced by drinking high levels of fructose augments adrenergic nerve-mediated vasoconstriction and suppresses vasodilatation mediated by calcitonin gene-related peptide (CGRP)-containing (CGRPergic) vasodilator nerves. In this study, the ...
journal_title:British journal of pharmacology
pub_type: 杂志文章
doi:10.1038/bjp.2008.8
更新日期:2008-04-01 00:00:00
abstract::Forty-eight isolated rat hearts were perfused with Krebs solution and with [(3)H]-(-)-noradrenaline ([(3)H]-NA) containing 4.5 nCi/ml in 50 ng/ml, as described by Iversen (1963). To groups of six, cocaine was added to [(3)H]-NA in concentrations of 400 nM, 2 and 10 muM. To the rest Tween 80, 25 mug/ml was added to [(3...
journal_title:British journal of pharmacology
pub_type: 杂志文章
doi:10.1111/j.1476-5381.1974.tb10686.x
更新日期:1974-07-01 00:00:00