Abstract:
:1 Cumulative concentration-response relationships for the chronotropic effects of histamine, oxymetazoline, clonidine and thirteen clonidine-like imidazolidine derivatives were examined in isolated spontaneously beating guinea-pig atria.2 The following compounds induced positive chronotropic effects: histamine, clonidine (2,6-dichloro-phenyliminoimidazolidine) and the 2,6-dibromo, 2,6-dimethyl, 2,6-diethyl, 2,6-dihydroxy, 2,4,6-trimethyl, 3,4-dihydroxy and 2-methyl-5-fluoro analogues of clonidine. These compounds appeared to act as partial agonists on histamine H(2)-receptors, with potencies ranging from one tenth to one hundredth and intrinsic activities from approximately 20% to 75% of those of histamine.3 The following compounds did not induce positive chronotropic effects but rather decreased the atrial rate, usually at high concentrations: oxymetazoline and the 2,3-dichloro, 4-dichloro, 5-dichloro, 2-chloro-4-methyl, 2-methyl-5-chloro, 2,4,6-trichloro analogues of clonidine.4 The effects of histamine were antagonized by cimetidine, the pA(2) value being 6.68 (s.e. mean = 0.16, n = 3), and also in a concentration-dependent manner by clonidine. Cimetidine antagonized the response to clonidine in a concentration-dependent manner; however, high concentrations of cimetidine depressed the maximal response to clonidine and the slope of the concentration-response curve was no longer parallel to the control curve.5 The effects of the other compounds which induced positive chronotropic effects were also antagonized by cimetidine (1 mumol/l); however, the effect of the 3,4-dihydroxy derivative was unaffected by cimetidine (1 mumol/l) but was abolished by propranolol (0.3 mumol/l).6 In general, phenyliminoimidazolidine derivatives with 2,6-substitution on the phenyl ring are active on histamine H(2)-receptors, whereas derivatives with 2,3-, 2,4- or 2,5-substitutions are weakly active or inactive. Thus the restriction imposed on the free rotation of the phenyl ring about the carbon-imino nitrogen bond by the introduction of two ortho substituents appears to result in increased agonist activity on the histamine H(2)-receptor. The introduction of substituents in the 3, 4 or 5 positions in the phenyl ring may lead to compounds sterically hindered from combining with the histamine H(2)-receptor.7 There is no apparent relationship between the activities of clonidine-like imidazolidine derivatives as agonists on histamine H(2)-receptors and their hypotensive activities (as reported in the literature).
journal_name
Br J Pharmacoljournal_title
British journal of pharmacologyauthors
McCulloch MW,Medgett IC,Rand MJ,Story DFdoi
10.1111/j.1476-5381.1980.tb07028.xsubject
Has Abstractpub_date
1980-07-01 00:00:00pages
397-405issue
3eissn
0007-1188issn
1476-5381journal_volume
69pub_type
杂志文章abstract::1. The effect on membrane currents of infection of mouse neuroblastoma NA cells with rabies virus was studied by using the whole-cell patch clamp technique. 2. Three types of membrane currents, namely voltage-dependent Na+ current (I(Na)), delayed rectifier K+ current (I(K-DR)) and inward rectifier K+ current (I(K-IR)...
journal_title:British journal of pharmacology
pub_type: 杂志文章
doi:10.1038/sj.bjp.0702473
更新日期:1999-04-01 00:00:00
abstract::1 A method is described for repeated sampling of plasma noradrenaline (NA) in freely moving rats. Na concentration does not change during the day or after adrenalectomy. 2 Exogenous NA has a half-life of 1.5 min; drugs which block neuronal and extra-neuronal uptake lengthen this to 6.3 min. 3 Swim-stress leads to a st...
journal_title:British journal of pharmacology
pub_type: 杂志文章
doi:10.1111/j.1476-5381.1978.tb17305.x
更新日期:1978-10-01 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::1. We studied the role of bradykinin (BK) and its active metabolite Des-Arg9-BK on noradrenaline release in association with the incidence of ventricular arrhythmias at reperfusion of the ischaemic myocardium. 2. Experiments were performed in Langendorff perfused isolated hearts of rats subjected to 30 min no flow fol...
journal_title:British journal of pharmacology
pub_type: 杂志文章
doi:10.1111/j.1476-5381.1993.tb12802.x
更新日期:1993-02-01 00:00:00
abstract::1 The prostaglandin synthesizing enzymes were found to be present in fat cell ghosts isolated from rabbit adipose tissue. 2 Prostaglandin E2 (PGE2) and PGF2, were synthesized by ghosts after stimulation with adrenocorticotrophic hormone (ACTH). 3 Indomethacin was found to inhibit this synthesis but not the synthesis o...
journal_title:British journal of pharmacology
pub_type: 杂志文章
doi:
更新日期:1979-11-01 00:00:00
abstract::The effects of dopamine receptor and alpha-adrenoceptor agonists and antagonists on the stimulation-evoked overflow of radioactivity from strips of dog saphenous vein previously loaded with [3H]-noradrenaline have been examined alone and in combination. In the presence of neuronal and extraneuronal catecholamine uptak...
journal_title:British journal of pharmacology
pub_type: 杂志文章
doi:10.1111/j.1476-5381.1984.tb10098.x
更新日期:1984-03-01 00:00:00
abstract::The cardiovascular effects of doxazosin, a quinazoline derivative related to prasozin were investigated and compared to prazosin in the rabbit. Radioligand binding studies using rabbit cerebral membranes showed that both doxazosin and prazosin were roughly equipotent at displacing [3H]-prazosin from specific binding s...
journal_title:British journal of pharmacology
pub_type: 杂志文章
doi:10.1111/j.1476-5381.1985.tb09437.x
更新日期:1985-09-01 00:00:00
abstract::1. The relationship between the capacity of the chick biventer preparation, both intact tissue and homogenate, to inactivate acetylcholine and the ability of eserine to increase the sensitivity of the tissue to acetylcholine have been investigated.2. At concentrations of eserine of 2.69 x 10(-9)M and 2.69 x 10(-8)M th...
journal_title:British journal of pharmacology
pub_type: 杂志文章
doi:10.1111/j.1476-5381.1971.tb07126.x
更新日期:1971-07-01 00:00:00
abstract::The severity of anaemic decerebrate rigidity was quantitatively determined by measuring the frequency of electromyographic potentials in the rat. Some oxazolidinones markedly reduced the severity of this decerebrate rigidity in a dose-dependent manner, (4S,5R)-4-(2-methylpropyl)-3- [3-(perhydroazepin-1-yl)propyl]-5-ph...
journal_title:British journal of pharmacology
pub_type: 杂志文章
doi:10.1111/j.1476-5381.1986.tb11138.x
更新日期:1986-09-01 00:00:00
abstract::1. TRPM2 is a Ca2+ -permeable nonselective cation channel activated by intracellular ADP-ribose (ADPR) and by hydrogen peroxide (H2O2). We investigated the modulation of TRPM2 activity by N-(p-amylcinnamoyl)anthranilic acid (ACA). ACA has previously been reported to inhibit phospholipase A2 (PLA2). 2. Using patch-clam...
journal_title:British journal of pharmacology
pub_type: 杂志文章
doi:10.1038/sj.bjp.0706739
更新日期:2006-06-01 00:00:00
abstract:BACKGROUND AND PURPOSE:GoSlo-SR compounds are efficacious BK (KCa 1.1) channel openers, but little is known about their mechanism of action or effect on bladder contractility. We examined the effects of two closely related compounds on BK currents and bladder contractions. EXPERIMENTAL APPROACH:A combination of electr...
journal_title:British journal of pharmacology
pub_type: 杂志文章
doi:10.1111/bph.13085
更新日期:2015-05-01 00:00:00
abstract::The electrically-evoked contractions of the rat vas deferens were selectively inhibited by beta-endorphin, the preparation being much less sensitive to enkephalins and narcotic analgesic drugs. However, introduction of D-Ala in position 2 of [Leu]-enkephalin enhanced the activity of the opioid peptide to the order of ...
journal_title:British journal of pharmacology
pub_type: 杂志文章
doi:10.1111/j.1476-5381.1978.tb08653.x
更新日期:1978-11-01 00:00:00
abstract::1. The modulation of L-type calcium channel current (ICa) by fendiline, a diphenylalkylamine type of calcium channel blocker was investigated on guinea-pig ventricular myocytes by use of the whole-cell patch-clamp technique. 2. Fendiline-induced block of ICa is accompanied by modulation of the channel kinetics in a co...
journal_title:British journal of pharmacology
pub_type: 杂志文章
doi:10.1111/j.1476-5381.1992.tb14308.x
更新日期:1992-05-01 00:00:00
abstract::A new canine model of endotoxin shock has been developed in which spontaneous recovery of cardiovascular function is largely prevented, the haemodynamic effects of anaesthesia are minimized and intravascular volume replacement is given. This model has been evaluated using two groups of five adult mongrel dogs anaesthe...
journal_title:British journal of pharmacology
pub_type: 杂志文章
doi:10.1111/j.1476-5381.1984.tb16504.x
更新日期:1984-10-01 00:00:00
abstract::1. Increased calcium (Ca2+) influx has been incriminated as a potential pathological mechanism in the chronic skeletal muscle degeneration exhibited by Duchenne muscular dystrophy (DMD) patients. We have studied the influence of the glucocorticoid alpha-methylprednisolone (PDN), the only drug known to have a beneficia...
journal_title:British journal of pharmacology
pub_type: 杂志文章
doi:10.1111/j.1476-5381.1995.tb15930.x
更新日期:1995-12-01 00:00:00
abstract:UNLABELLED:Increasing evidence suggests that an overactive endocannabinoid system (ECS) may contribute to the development of diabetes by promoting energy intake and storage, impairing both glucose and lipid metabolism, by exerting pro-apoptotic effects in pancreatic beta cells and by facilitating inflammation in pancre...
journal_title:British journal of pharmacology
pub_type: 杂志文章,评审
doi:10.1111/bph.13226
更新日期:2016-04-01 00:00:00
abstract::1 Morphine, Met-enkephalin, kyotorphin and D-phenylalanine have been applied by microiontophoresis to neurones in the globus pallidus and cerebral cortex of rats anaesthetized with urethane. 2 In the pallidum, most cells were inhibited by all the agonists, with a high correspondence between cells inhibited by Met-enke...
journal_title:British journal of pharmacology
pub_type: 杂志文章
doi:10.1111/j.1476-5381.1983.tb10525.x
更新日期:1983-05-01 00:00:00
abstract::Glycogen synthase kinase 3 (GSK3), a constitutively acting multi-functional serine threonine kinase is involved in diverse physiological pathways ranging from metabolism, cell cycle, gene expression, development and oncogenesis to neuroprotection. These diverse multiple functions attributed to GSK3 can be explained by...
journal_title:British journal of pharmacology
pub_type: 杂志文章,评审
doi:10.1111/j.1476-5381.2008.00085.x
更新日期:2009-03-01 00:00:00
abstract::Research into the pharmacology of individual cannabinoids that began in the 1940s, several decades after the presence of a cannabinoid was first detected in cannabis, is concisely reviewed. Also described is how this pharmacological research led to the discovery of cannabinoid CB(1) and CB(2) receptors and of endogeno...
journal_title:British journal of pharmacology
pub_type: 历史文章,杂志文章
doi:10.1038/sj.bjp.0706406
更新日期:2006-01-01 00:00:00
abstract::1. The rat spinal cord in vitro has been used to assess the effect of 6-cyano-7-nitroquinoxaline-2,3-dione (CNQX) on the dorsal root evoked extracellular ventral root reflex (DR-VRR) and the intracellular excitatory postsynaptic potential (e.p.s.p.) in ventral horn neurones and motoneurones. 2. CNQX (1-5 microM) produ...
journal_title:British journal of pharmacology
pub_type: 杂志文章
doi:10.1111/j.1476-5381.1992.tb12754.x
更新日期:1992-10-01 00:00:00
abstract:BACKGROUND AND PURPOSE:N-arachidonoyl 5-HT (NA-5HT) has anti-nociceptive effects reported to be mediated by inhibitory actions at the transient receptor potential vanilloid receptor 1 (TRPV1) and fatty acid amide hydrolase (FAAH). Anandamide and N-arachidonoyl dopamine (NA-DA), endocannabinoids that activate TRPV1 or a...
journal_title:British journal of pharmacology
pub_type: 杂志文章
doi:10.1111/j.1476-5381.2012.02047.x
更新日期:2012-11-01 00:00:00
abstract:BACKGROUND AND PURPOSE:While remifentanil can be used either during labour or fetal surgery, more should be known about the transplacental transfer of this opioid. The aim of this study was to investigate the placental transfer and haemodynamic effects of remifentanil after i.v. administration to pregnant ewes. EXPERI...
journal_title:British journal of pharmacology
pub_type: 杂志文章
doi:10.1111/j.1476-5381.2010.00783.x
更新日期:2010-12-01 00:00:00
abstract:BACKGROUND AND PURPOSE:Dysfunction and injury of endothelial cells in the pulmonary artery play critical roles in the hypertension induced by chronic hypoxia. One consequence of hypoxia is increased activity of 15-hydroxyprostaglandin dehydrogenase (PGDH). Here, we have explored, in detail, the effects of hypoxia on th...
journal_title:British journal of pharmacology
pub_type: 杂志文章
doi:10.1111/bph.12594
更新日期:2014-07-01 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. Phenylarsine oxide (PAO) is commonly used to inhibit tyrosine phosphatase activity. However, PAO can affect a variety of different processes because of its ability to promote sulfhydryl oxidation. In the present study, we investigated the effects that PAO has on basal and beta-adrenergically stimulated L-type Ca(2+...
journal_title:British journal of pharmacology
pub_type: 杂志文章
doi:10.1038/sj.bjp.0705845
更新日期:2004-06-01 00:00:00
abstract::1. Lowering of the extracellular Mg(2+)-concentration induces various patterns of epileptiform activity in combined rat entorhinal cortex-hippocampal brain slices. After a prolonged period of exposure to Mg(2+)-free medium seizure-like events in the entorhinal cortex change to a state of late recurrent discharges whic...
journal_title:British journal of pharmacology
pub_type: 杂志文章
doi:10.1111/j.1476-5381.1996.tb15710.x
更新日期:1996-10-01 00:00:00
abstract::Bradykinin, angiotensin II, arginine vasopressin (AVP) or des-amino-D-arginine vasopressin (DDAVP) were administered by intravenous infusion to 10 healthy men. The concentration of 6-oxo-prostaglandin F1 alpha (6-oxo-PGF1 alpha), the stable hydrolysis product of prostacyclin (PGI2), was measured in plasma using gas ch...
journal_title:British journal of pharmacology
pub_type: 杂志文章
doi:10.1111/j.1476-5381.1986.tb10177.x
更新日期:1986-01-01 00:00:00
abstract:BACKGROUND AND PURPOSE:K(v)11.1 channels are involved in regulating cellular excitability in various tissues including brain, heart and smooth muscle. In these tissues, at least two isoforms, K(v)11.1a and K(v)11.1b, with different kinetics, are expressed. K(v)11.1 activators are potential therapeutic agents, but their...
journal_title:British journal of pharmacology
pub_type: 杂志文章
doi:10.1111/j.1476-5381.2010.00897.x
更新日期:2010-10-01 00:00:00
abstract:BACKGROUND AND PURPOSE:Inflammasomes are multimeric complexes that facilitate caspase-1-mediated processing of the pro-inflammatory cytokines IL-1β and IL-18. Clinical hypertension is associated with renal inflammation and elevated circulating levels of IL-1β and IL-18. Therefore, we investigated whether hypertension i...
journal_title:British journal of pharmacology
pub_type: 杂志文章
doi:10.1111/bph.13230
更新日期:2016-02-01 00:00:00
abstract:BACKGROUND AND PURPOSE:Tanshinol borneol ester (DBZ) is a novel synthetic compound derived from Dantonic® , a botanical drug approved in 26 countries outside the United States for angina pectoris and currently undergoing FDA Phase III clinical trial. Here, we investigated the angiogenic effects of (S)-DBZ and (R)-DBZ i...
journal_title:British journal of pharmacology
pub_type: 杂志文章
doi:10.1111/bph.14714
更新日期:2019-09-01 00:00:00