Abstract:
:1. The effects of diprafenone and propafenone on transmembrane action potential were examined and compared in papillary muscles and single ventricular myocytes isolated from guinea-pig hearts. 2. In papillary muscles, both diprafenone and propafenone > or = 10(-6) M caused a significant and dose-dependent decrease in the maximum upstroke velocity (Vmax) of the action potential. 3. In the presence of either drug, trains of stimuli at rates > or = 0.1 Hz led to an exponential decline in Vmax. A time constant (tau R) for Vmax recovery from the use-dependent block was 15.5 s for diprafenone and 8.8 s for propafenone. 4. The use-dependent block of Vmax with diprafenone was enhanced when the resting potential was depolarized by high (8, 10 mM) [K+]o, whereas that with propafenone was virtually unchanged. tau R with diprafenone was shortened by the depolarization, while that with propafenone was rather prolonged. 5. In single myocytes perfused with diprafenone or propafenone, 10 ms conditioning clamp to 0 mV caused a significant decrease in Vmax of subsequent action potential. A prolongation of the clamp pulse duration resulted in a modest enhancement of the Vmax inhibition with diprafenone, while a large enhancement of the Vmax inhibition occurred with propafenone. 6. These findings suggest that diprafenone, like propafenone, may block the sodium channel during both the activated and inactivated states. The relative contribution of inactivation block is less important for diprafenone than for propafenone. The different voltage-dependence of use-dependent block with diprafenone from propafenone would contribute to its high antiarrhythmic potency.
journal_name
Br J Pharmacoljournal_title
British journal of pharmacologyauthors
Kodama I,Suzuki R,Honjo H,Toyama Jdoi
10.1111/j.1476-5381.1992.tb14529.xsubject
Has Abstractpub_date
1992-11-01 00:00:00pages
813-20issue
3eissn
0007-1188issn
1476-5381journal_volume
107pub_type
杂志文章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 ...
journal_title:British journal of pharmacology
pub_type: 杂志文章
doi:10.1111/j.1476-5381.1987.tb11198.x
更新日期:1987-03-01 00:00:00
abstract::The neuroprotective drug riluzole has multiple effects on cellular signaling. We found that riluzole rapidly and reversibly inhibited spontaneous Ca2+ oscillations in both immortalized GnRH-secreting hypothalamic neurons (GT1 cells) and in the prolactin and growth-hormone-secreting GH3 cell line. At lower concentratio...
journal_title:British journal of pharmacology
pub_type: 杂志文章
doi:10.1038/sj.bjp.0705491
更新日期:2003-11-01 00:00:00
abstract:BACKGROUND AND PURPOSE:High resting heart rate is a predictor for total and cardiovascular mortality independent of other risk factors in patients with coronary artery disease. We tested the hypothesis that a reduction of resting heart rate with the cardiac pacemaker I(f) current inhibitor ivabradine prevents the endot...
journal_title:British journal of pharmacology
pub_type: 杂志文章
doi:10.1038/bjp.2008.116
更新日期:2008-06-01 00:00:00
abstract:BACKGROUND AND PURPOSE:Cultured pre-adipocytes accumulate and metabolize zidovudine (ZDV), but its mode of accumulation into these cells is unclear. We investigated the mode of accumulation of [(3)H]-ZDV, and the impact of changes in external pH and modulators of drug transporters on its accumulation and metabolism. E...
journal_title:British journal of pharmacology
pub_type: 杂志文章
doi:10.1111/j.1476-5381.2009.00552.x
更新日期:2010-01-01 00:00:00
abstract::Perivascular adipose tissue (PVAT) is now recognized as an active player in vascular homeostasis. The expansion of PVAT in obesity and its possible role in vascular dysfunction have attracted much interest. In terms of the regulation of vascular tone and blood pressure, PVAT has been shown to release vasoactive mediat...
journal_title:British journal of pharmacology
pub_type: 杂志文章,评审
doi:10.1111/bph.13767
更新日期:2017-10-01 00:00:00
abstract:BACKGROUND AND PURPOSE:Melanocortins reverse circulatory shock and improve survival by counteracting the systemic inflammatory response, and through the activation of the vagus nerve-mediated cholinergic anti-inflammatory pathway. To gain insight into the potential therapeutic value of melanocortins against multiple or...
journal_title:British journal of pharmacology
pub_type: 杂志文章
doi:10.1111/j.1476-5381.2010.01098.x
更新日期:2011-02-01 00:00:00
abstract::1. Catecholamine release from cat adrenal glands perfused at a high rate (4 ml min-1) at 37 degrees C with modified Krebs solutions lacking Ca and containing 1.2 mM K (hyperpolarizing solution) or 118 mM K (depolarizing solution) was triggered by 10-s pulses of Ca (0.5 mM) in the presence of 118 mM K. Hyperpolarized g...
journal_title:British journal of pharmacology
pub_type: 杂志文章
doi:10.1111/j.1476-5381.1989.tb11874.x
更新日期:1989-03-01 00:00:00
abstract:BACKGROUND AND PURPOSE:Venoms are a rich source of ligands for ion channels, but very little is known about their capacity to modulate G-protein coupled receptor (GPCR) activity. We developed a strategy to identify novel toxins targeting GPCRs. EXPERIMENTAL APPROACH:We studied the interactions of mamba venom fractions...
journal_title:British journal of pharmacology
pub_type: 杂志文章
doi:10.1111/j.1476-5381.2009.00532.x
更新日期:2010-01-01 00:00:00
abstract::1. The effector mechanism of intestinal necrosis in rat anaphylaxis was studied following several complementary approaches: (i) the use of monoclonal antibodies (mAb) belonging to different classes (IgG1, IgG2b and IgE anti-DNP), (ii) the assay of mediators, and (iii) the use of pharmacological tools. 2. Lethality and...
journal_title:British journal of pharmacology
pub_type: 杂志文章
doi:10.1111/j.1476-5381.1994.tb13197.x
更新日期:1994-08-01 00:00:00
abstract::1. Murine left atrium lacks inotropic beta(2)-adrenoceptor function. We investigated whether beta(2)-adrenoceptors are involved in the cardiostimulant effects of (-)-adrenaline on spontaneously beating right atria and paced right ventricular myocardium of C57BL6 mice. We also studied a negative inotropic effect of (-)...
journal_title:British journal of pharmacology
pub_type: 杂志文章
doi:10.1038/sj.bjp.0704700
更新日期:2002-05-01 00:00:00
abstract::1. This study analyses the neural pathway involved in the modulation of gastric motor function by stress. 2. Systemic administration of low doses of endotoxin (40 microg kg(-1), i.v.) prevents the increase in gastric tone induced by 2-deoxy-D-glucose (200 mg kg(-1), i.v., 2-DG) in urethane-anaesthetized rats. 3. Funct...
journal_title:British journal of pharmacology
pub_type: 杂志文章
doi:10.1038/sj.bjp.0704258
更新日期:2001-09-01 00:00:00
abstract::1. ATP, UTP, ADP and ADP-beta-S elicited Ca2+ -signals in cultured aortic smooth muscle cells although ADP, UDP and ADP-beta-S gave approximately 40% of the maximal response seen with ATP and UTP. Adenosine, AMP or alpha,beta-methylene-ATP had no effect. These responses were attributed to P2Y2/4 and P2Y1 receptors, wh...
journal_title:British journal of pharmacology
pub_type: 杂志文章
doi:10.1038/sj.bjp.0702470
更新日期:1999-04-01 00:00:00
abstract::1 The vasopressor response to prostaglandin F2 alpha (PGF2 alpha) and to ((15S)-hydroxy-11 alpha, 9 alpha-(epoxymethano)-prosta-5Z, 13E-dienoic acid) (U-46619) in the canine isolated lung lobe was significantly attenuated following the administration of verapamil. 2 The pressor response to arachidonic acid (AA) was no...
journal_title:British journal of pharmacology
pub_type: 杂志文章
doi:10.1111/j.1476-5381.1981.tb16777.x
更新日期:1981-05-01 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
abstract::We synthesized a small-molecule opioid receptor-like 1 (ORL1) receptor agonist, 2-{3-[1-((1R)-acenaphthen-1-yl)piperidin-4-yl]-2,3-dihydro-2-oxo-benzimidazol-1-yl}-N-methylacetamide (W-212393), and investigated its effect on the circadian body temperature rhythm of rats. W-212393 has high affinity for ORL1 receptors i...
journal_title:British journal of pharmacology
pub_type: 杂志文章
doi:10.1038/sj.bjp.0706311
更新日期:2005-09-01 00:00:00
abstract::Bacteria have existed on Earth for three billion years or so and have become adept at protecting themselves against toxic chemicals. Antibiotics have been in clinical use for a little more than 6 decades. That antibiotic resistance is now a major clinical problem all over the world attests to the success and speed of ...
journal_title:British journal of pharmacology
pub_type: 杂志文章,评审
doi:10.1038/sj.bjp.0707607
更新日期:2008-03-01 00:00:00
abstract::1 The effects of the prostaglandin synthetase inhibitor, indomethacin and the prostaglandin antagonist SC-19220 (1-acetyl-2-[8-chloro-10,11-dihydrodibenz (b,f) (1,4)oxazepine-10-carbonyl] hydrazine), were examined on the tone of the guinea-pig isolated tracheal preparation and on the responses of the preparation to pr...
journal_title:British journal of pharmacology
pub_type: 杂志文章
doi:10.1111/j.1476-5381.1974.tb09724.x
更新日期:1974-12-01 00:00:00
abstract::(1) UNC-49B and UNC-49C are gamma-aminobutyric acid (GABA) receptor subunits encoded by the Caenorhabditis elegans unc-49 gene. UNC-49B forms a homomeric GABA receptor, or can co-assemble with UNC-49C to form a heteromeric receptor. The pharmacological properties of UNC-49B homomers and UNC-49B/C heteromers were inves...
journal_title:British journal of pharmacology
pub_type: 杂志文章
doi:10.1038/sj.bjp.0705119
更新日期:2003-03-01 00:00:00
abstract::Knowledge of the cardiac safety of emerging new drugs is an important aspect of assuring the expeditious advancement of the best candidates targeted at unmet medical needs while also assuring the safety of clinical trial subjects or patients. Present methodologies for assessing drug-induced torsades de pointes (TdP) a...
journal_title:British journal of pharmacology
pub_type:
doi:10.1038/bjp.2008.279
更新日期:2008-08-01 00:00:00
abstract::A dispersed rat anterior pituitary cell system has been used to investigate the effects of cyproheptadine and metergoline on prolactin secretion. Both drugs were potent inhibitors of prolactin secretion. However, the inhibition was not antagonized by either 5-hydroxytryptamine or a variety of dopamine antagonists. We ...
journal_title:British journal of pharmacology
pub_type: 杂志文章
doi:10.1111/j.1476-5381.1980.tb10896.x
更新日期:1980-09-01 00:00:00
abstract::1. Goblet cell secretion in guinea-pig airways is under neural control. Opioids have previously been shown to inhibit neurogenic plasma exudation and bronchoconstriction in guinea-pig airways. We have now examined the effects of morphine and opioid peptides on tracheal goblet cell secretion induced by either electrica...
journal_title:British journal of pharmacology
pub_type: 杂志文章
doi:10.1111/j.1476-5381.1992.tb14259.x
更新日期:1992-02-01 00:00:00
abstract::Ligands targeting GPCRs can be categorized according to their intrinsic efficacy to trigger a specific, receptor-mediated response. A ligand endowed with the same level of efficacy as the endogenous agonist can be classified as a full agonist, whereas a compound that displays greater efficacy, that is, higher receptor...
journal_title:British journal of pharmacology
pub_type: 杂志文章,评审
doi:10.1111/bph.13278
更新日期:2016-10-01 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::The effect of the imidazolidine Sgd 101/75 (2-[2-methylindazol-4-imino]-imidazolidine HCl) on blood pressure, as well as its alpha-adrenoceptor agonist activity and affinity for these receptors, were examined in various animal preparations. After both intravenous administration to conscious spontaneously hypertensive ...
journal_title:British journal of pharmacology
pub_type: 杂志文章
doi:10.1111/j.1476-5381.1984.tb10072.x
更新日期:1984-02-01 00:00:00
abstract::1. To examine further the potentiation by endothelin-1 on the vascular response to sympathetic stimulation, we studied the isometric response of isolated segments, 2 mm long, from the rabbit central ear artery to electrical field stimulation (1-8 Hz), under different conditions, at 37 degrees C and during cooling (30 ...
journal_title:British journal of pharmacology
pub_type: 杂志文章
doi:10.1038/sj.bjp.0701324
更新日期:1997-08-01 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::The contractile responses of the rabbit isolated coeliac and mesenteric arteries to five agonists (angiotensin, adrenaline, histamine, acetylcholine and 5-hydroxytryptamine), but not to K+, were potentiated by indomethacin (8.4 microM) The potentiation was similar whether indomethacin was added 1 h before or during th...
journal_title:British journal of pharmacology
pub_type: 杂志文章
doi:10.1111/j.1476-5381.1983.tb10714.x
更新日期:1983-11-01 00:00:00
abstract::Although previous reports have suggested that the sigma 1 (sigma(1)) receptor may be involved in pain sensation, its specific site of action has not been elucidated. The aim of present study was to determine the role of the spinal sigma(1) receptor in formalin-induced pain behavior, spinal cord Fos expression and phos...
journal_title:British journal of pharmacology
pub_type: 杂志文章
doi:10.1038/sj.bjp.0706764
更新日期:2006-06-01 00:00:00
abstract::1. Block by philanthotoxin-343 (PhTX-343), a neurotoxin from wasps, of ionic currents mediated through neuronal nicotinic acetylcholine (ACh) receptor/channels was characterized in rat phaeochromocytoma PC12 cells, by use of whole cell voltage-clamp techniques. 2. In the cells held at -60 mV, PhTX-343 at 0.1 and 1 mic...
journal_title:British journal of pharmacology
pub_type: 杂志文章
doi:10.1038/sj.bjp.0701373
更新日期:1997-09-01 00:00:00
abstract:BACKGROUND AND PURPOSE:Haem oxygenase-1 (HO-1) is induced by thiazolidinediones including rosiglitazone and exerts anti-inflammatory effects in various models. However, the molecular mechanisms underlying rosiglitazone-induced HO-1 expression remain largely unknown in human pulmonary alveolar epithelial cells (HPAEpiCs...
journal_title:British journal of pharmacology
pub_type: 杂志文章
doi:10.1111/bph.14465
更新日期:2018-10-01 00:00:00