Abstract:
:The profiles of four analogues of idazoxan have been examined at alpha-adrenoceptors and the results compared to those obtained with idazoxan and yohimbine. The compounds possessed either a methyl (RX 801079), ethyl (RX 811033), n-propyl (RX 811054) or isopropenyl (RX 811005) group at the two position of idazoxan. The rank order of antagonist potency against UK-14,304 at prejunctional alpha 2-adrenoceptors of the rat isolated vas deferens was RX 811054 greater than RX 811033 greater than idazoxan greater than RX 811005 greater than yohimbine = RX 801079. All compounds were competitive antagonists. The rank order of antagonist potency against noradrenaline at postjunctional alpha 1-adrenoceptors of the rat isolated anococcygeus muscle was RX 811054 = RX 811033 = idazoxan = yohimbine greater than RX 811005 = RX801079. All compounds were competitive antagonists. The rank order of alpha-adrenoceptor selectivity (alpha 2/alpha 1) was RX 811005 greater than RX 801079 greater than RX 811054 greater than RX 811033 greater than idazoxan greater than yohimbine. In pithed rats, intravenous administration of all compounds fully reversed the prejunctional alpha 2-adrenoceptor agonist effects of clonidine and guanabenz on electrically-induced contractions of the vas deferens and anococcygeus muscle respectively. In pithed rats the rank order of antagonist potency against UK-14,304 at cardiac prejunctional alpha 2-adrenoceptors was RX 811054 greater than RX 811033 greater than idazoxan greater than yohimbine greater than RX 811005 greater than RX 801079. In contrast, the rank order of antagonist potency against cirazoline pressor effects (vascular postjunctional alpha 1-adrenoceptors) was RX 811054 greater than RX 811033 greater than yohimbine greater than idazoxan greater than RX 811005 greater than RX 801079. The rank order of alpha 2-adrenoceptor selectivity was RX 811033 = RX 801079 = RX 801005 greater than RX 811054 greater than idazoxan greater than yohimbine. Although idazoxan produced contractions of the anococcygeus muscle and increased blood pressure in pithed rats, three of the analogues (RX 811005, RX 801079 and RX 811033) were inactive. In conclusion, alkyl substitution in the 2-position of idazoxan can enhance either alpha 2-adrenoceptor antagonist potency or selectivity or both and furthermore, the weak partial alpha 1-adrenoceptor agonist properties of idazoxan can be removed.
journal_name
Br J Pharmacoljournal_title
British journal of pharmacologyauthors
Doxey JC,Roach AG,Strachan DA,Virdee NKdoi
10.1111/j.1476-5381.1984.tb16225.xsubject
Has Abstractpub_date
1984-11-01 00:00:00pages
713-22issue
3eissn
0007-1188issn
1476-5381journal_volume
83pub_type
杂志文章abstract::The histamine H3 receptor, first described in 1983 as a histamine autoreceptor and later shown to also function as a heteroreceptor that regulates the release of other neurotransmitters, has been the focus of research by numerous laboratories as it represents an attractive drug target for a number of indications inclu...
journal_title:British journal of pharmacology
pub_type: 杂志文章,评审
doi:10.1038/bjp.2008.147
更新日期:2008-07-01 00:00:00
abstract::1. The modification by Bay K 8644 of the vasodilator effects of nifedipine, diltiazem, nicorandil and nitroglycerin was investigated in the femoral arterial bed of anaesthetized dogs. 2. The right femoral artery was cannulated and its arterial bed was perfused with autologous blood at a constant pressure slightly high...
journal_title:British journal of pharmacology
pub_type: 杂志文章
doi:10.1111/j.1476-5381.1988.tb11415.x
更新日期:1988-01-01 00:00:00
abstract::1. The aims of this study were first, to examine whether deficits in nerve conduction in streptozotocin-diabetic rats could be reversed by a 10% dietary supplement of evening primrose oil. Second, to determine the time-course of reversal, and third, to assess whether the effects could be blocked by the cyclo-oxygenase...
journal_title:British journal of pharmacology
pub_type: 杂志文章
doi:10.1111/j.1476-5381.1993.tb13716.x
更新日期:1993-08-01 00:00:00
abstract::Vasoactive intestinal peptide (VIP) caused concentration-dependent relaxation in precontracted segments of trachea, hilar bronchus, intrapulmonary bronchus and intrapulmonary artery (IPA) isolated from cat lungs. VIP-induced relaxation responses were abolished by preincubation of tissues with the proteolytic enzyme, a...
journal_title:British journal of pharmacology
pub_type: 杂志文章
doi:10.1111/j.1476-5381.1984.tb10766.x
更新日期:1984-06-01 00:00:00
abstract:BACKGROUND AND PURPOSE:Non-alcoholic hepatic fatty liver disease (NAFLD) is a manifestation of the metabolic syndrome in the liver and non-alcoholic steatohepatitis (NASH) represents its advanced stage. R17 derived from bouchardatine, shows benefits in the metabolic syndrome, but has not been tested in the liver. The p...
journal_title:British journal of pharmacology
pub_type: 杂志文章
doi:10.1111/bph.14713
更新日期:2019-08-01 00:00:00
abstract::1. The effects of low oxygen tension on tone and on the responsiveness to contractile and relaxant agents were examined on circumflex coronary artery rings isolated from sheep. 2. When artery rings (2-2.5 mm o.d.) were set at their optimal resting tension, introduction of hypoxia (0% O2) caused a sustained contraction...
journal_title:British journal of pharmacology
pub_type: 杂志文章
doi:10.1111/j.1476-5381.1989.tb11894.x
更新日期:1989-04-01 00:00:00
abstract::1. Electrical stimulation of the mid-brain raphé in anaesthetized adrenalectomized rats produced a significant decrease in the forebrain content of 5-hydroxytryptamine (5-HT) and an increase in the concentration of 5-hydroxyindol-3-ylacetic acid (5-HIAA).2. Stimulation of peripheral sensory nerves did not influence ei...
journal_title:British journal of pharmacology
pub_type: 杂志文章
doi:10.1111/j.1476-5381.1970.tb09550.x
更新日期:1970-05-01 00:00:00
abstract::Leukotriene B4 (LTB4) is a potent leukocyte chemoattractant, acting on specific receptors, BLT receptors. The aim of this study was to examine the mechanism of action of LTB4 in the guinea-pig lung, using strips of lung parenchyma (GPLP), spirals of trachea (GPT) and bronchus (GPB) and rings of pulmonary artery (GPPA)...
journal_title:British journal of pharmacology
pub_type: 杂志文章
doi:10.1038/sj.bjp.0705641
更新日期:2004-02-01 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:BACKGROUND AND PURPOSE:Interstitial lung disease accounts for a group of chronic and progressive disorders associated with severe pulmonary vascular remodelling, peripheral vascular rarefaction and fibrosis, thus limiting lung function. We have previously shown that Akt is necessary for myofibroblast differentiation, a...
journal_title:British journal of pharmacology
pub_type: 杂志文章
doi:10.1111/bph.13203
更新日期:2015-08-01 00:00:00
abstract::1. The effect of adenosine A1-receptor and P2-purinoceptor agonists on [3H]-inositol phosphate accumulation has been investigated in CHO-K1 cells transfected with the human adenosine A1-receptor. 2. Adenosine receptor agonists stimulated [3H]-inositol phosphate accumulation in CHO-K1 cells with a rank potency order of...
journal_title:British journal of pharmacology
pub_type: 杂志文章
doi:10.1111/j.1476-5381.1995.tb16632.x
更新日期:1995-08-01 00:00:00
abstract::Effects of hypoxia on atrioventricular conduction were investigated in the Langendorff-perfused isolated heart of the rabbit with various extracellular calcium concentrations ([Ca2+]) as well as in the presence of verapamil, nifedipine, N-(6-aminohexyl)-5-chloro-1-naphthalenesulphonamide (W-7) and chlorpromazine. The ...
journal_title:British journal of pharmacology
pub_type: 杂志文章
doi:10.1111/j.1476-5381.1986.tb09496.x
更新日期:1986-05-01 00:00:00
abstract::1. CS-747 is a novel antiplatelet agent that generates an active metabolite, R-99224, in vivo. CS-747 itself was totally inactive in vitro. This study examined in vivo pharmacological profiles of CS-747 after single oral administration to rats. 2. Orally administered CS-747 (0.3 - 10 mg kg(-1)) partially but significa...
journal_title:British journal of pharmacology
pub_type: 杂志文章
doi:10.1038/sj.bjp.0703237
更新日期:2000-04-01 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::In recent years, late-stage clinical drug development that primarily focuses on urogenital targets has centered around four areas of medical need (both unmet need and aiming to improve on existing therapies). These include male sexual dysfunction (MSD), female sexual dysfunction (FSD), prostatic pathology (neoplastic,...
journal_title:British journal of pharmacology
pub_type: 杂志文章,评审
doi:10.1038/sj.bjp.0706638
更新日期:2006-02-01 00:00:00
abstract::Despite the importance of members of the GPCR superfamily as targets of a broad range of effective medicines many GPCRs remain poorly characterised. GPR84 is an example. Expression of GPR84 is strongly up regulated in immune cells in a range of pro-inflammatory settings and clinical trials to treat idiopathic pulmonar...
journal_title:British journal of pharmacology
pub_type: 杂志文章,评审
doi:10.1111/bph.15248
更新日期:2020-09-01 00:00:00
abstract::1. Sigma (sigma) receptors have generated a great deal of interest on the basis of their possible roles in various pathologies, including cytoprotection. Although the exact function of sigma-1 (sigma(1)) receptors is not yet known, their role in the regulation of intracellular Ca(2+) levels and sterol biosynthesis, fu...
journal_title:British journal of pharmacology
pub_type: 杂志文章
doi:10.1038/sj.bjp.0704626
更新日期:2002-04-01 00:00:00
abstract::1. Chronic administration of the benzodiazepine inverse agonist FG 7142 has previously been shown to induce seizure activity in mice. In the present study we have investigated the effects of acute and chronic treatment with FG 7142 in mice on the levels of acetylcholinesterase activity in cortex, hippocampus, midbrain...
journal_title:British journal of pharmacology
pub_type: 杂志文章
doi:10.1111/j.1476-5381.1990.tb14127.x
更新日期:1990-11-01 00:00:00
abstract::1. This study was undertaken to evaluate in vivo the influence of amiodarone on the effects of triiodothyronine (T3) in brown adipose tissue (BAT) which are independent of thyroid hormone synthesis and of the conversion of thyroxine (T4) to T3. Thyroidectomized rats were given a replacement dose of T3 (0.5 mg kg(-1) p...
journal_title:British journal of pharmacology
pub_type: 杂志文章
doi:10.1038/sj.bjp.0702456
更新日期:1999-03-01 00:00:00
abstract::Recent genome-wide analyses of rare and common sequence variations have brought greater clarity to the genetic architecture of pulmonary arterial hypertension and implicated novel genes in disease development. Transcriptional signatures have been reported in whole lung tissue, pulmonary vascular cells and peripheral c...
journal_title:British journal of pharmacology
pub_type: 杂志文章,评审
doi:10.1111/bph.15056
更新日期:2021-01-01 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. The inhibitory effect of erythrocyte suspensions and haemoglobin solutions on the response of the bovine retractor penis muscle (BRP) and the rat anococcygeus to field stimulation of their non-adrenergic non-cholinergic (NANC) nerves has been compared. Haemoglobin 3 microM greatly reduced the relaxant response in b...
journal_title:British journal of pharmacology
pub_type: 杂志文章
doi:10.1111/j.1476-5381.1989.tb12616.x
更新日期:1989-10-01 00:00:00
abstract::1. Steady state fever has been produced in rabbits with a priming injection followed by a sustaining infusion of homologous plasma containing endogenous pyrogen (EP). This fever appears to last as long as the infusion continues.2. Intravenous salicylate given 1 h after the start of the EP infusion produced only a smal...
journal_title:British journal of pharmacology
pub_type: 杂志文章
doi:10.1111/j.1476-5381.1971.tb08035.x
更新日期:1971-02-01 00:00:00
abstract::Until recently, hydrogen sulfide (H2 S) was exclusively viewed a toxic gas and an environmental hazard, with its toxicity primarily attributed to the inhibition of mitochondrial Complex IV, resulting in a shutdown of mitochondrial electron transport and cellular ATP generation. Work over the last decade established mu...
journal_title:British journal of pharmacology
pub_type: 杂志文章,评审
doi:10.1111/bph.12369
更新日期:2014-04-01 00:00:00
abstract::1. The distribution of sympathetic adrenergic nerves on the rat middle cerebral artery and on the arterioles which originated from it was determined by use of gloxylic histochemistry. 2. Whereas the middle cerebral artery and proximal arterioles arising from this artery received a sympathetic innervation, the distal r...
journal_title:British journal of pharmacology
pub_type: 杂志文章
doi:10.1111/j.1476-5381.1989.tb11884.x
更新日期:1989-04-01 00:00:00
abstract:BACKGROUND AND PURPOSE:Alterations in the tyrosine kinase enzyme RET are found in thyroid and lung cancer. While RET TK inhibitors (TKIs) are used to treat thyroid cancer and are in clinical trials for RET fusion-positive non-small cell lung cancer, the impact of mutations in the RET kinase domain on drug sensitivity i...
journal_title:British journal of pharmacology
pub_type: 杂志文章
doi:10.1111/bph.14395
更新日期:2018-09-01 00:00:00
abstract::The sensitivity of the uterus to the inhibition of contractions by salbutamol, diltiazem or nifedipine was assessed in the ovariectomized, post-partum rat by dose-response curves following bolus intravenous (i.v.) administration. These tests were performed before (day 1), immediately after a 20 h i.v. infusion of salb...
journal_title:British journal of pharmacology
pub_type: 杂志文章
doi:10.1111/j.1476-5381.1986.tb10238.x
更新日期:1986-07-01 00:00:00
abstract::1. Fenclozic acid (2-(4-chlorophenyl)thiazol-4-ylacetic acid; I.C.I. 54,450; "Myalex") is one representative of a new class of compounds with antiinflammatory, analgesic and antipyretic properties as evidenced by its activity in a variety of tests in rats, mice and guinea-pigs.2. In tests of short duration the potency...
journal_title:British journal of pharmacology
pub_type: 杂志文章
doi:10.1111/j.1476-5381.1969.tb08290.x
更新日期:1969-03-01 00:00:00
abstract::In circular smooth muscle cells of the guinea-pig stomach (antrum), diltiazem (10(-6)-10(-5)M) blocked the overshooting spike potential generated either spontaneously or by electrical stimulation in the presence of 2 mM tetraethylammonium chloride, but did not block the slow wave and the abortive spike potential. The ...
journal_title:British journal of pharmacology
pub_type: 杂志文章
doi:10.1111/j.1476-5381.1985.tb11100.x
更新日期:1985-12-01 00:00:00
abstract::Nociceptive tail flick latencies (TFL) were recorded in response to noxious thermal stimuli applied to lightly anaesthetized rats. The effects of intrathecally administered dopamine receptor agonists alone and combined with dopamine receptor antagonists were examined upon the TFL. Experiments were repeated on animals ...
journal_title:British journal of pharmacology
pub_type: 杂志文章
doi:10.1111/j.1476-5381.1987.tb16820.x
更新日期:1987-01-01 00:00:00