Abstract:
:1. Rabbit left atrial preparations driven electrically at different rates were used for studies on inotropic effects of cations, drugs and coupled pacing. Sino-atrial node-atrial preparations were used for investigating the chronotropic effect of noradrenaline.2. The contractile tension-driving rate relationship was moved upwards by an elevation of [Ca(++)]o, coupled pacing and noradrenaline. In preparations exposed to Na(+)-poor and K(+)-free solutions the contractile strength at low driving rates (6 to 30 c/min) was markedly enhanced, but at high rates (120 to 240 c/min) it was not influenced. The contractile strength was reduced at low [Ca(++)]o and at high [K(+)]o.3. The positive inotropic effect of noradrenaline was markedly inhibited by a reduction of [Ca(++)]o and to some extent by a reduction of [K(+)]o. The noradrenaline-inotropy was not appreciably affected by an elevation of [Ca(++)]o and a reduction of [Na(+)]o.4. Cardiac excitability studied in preparations driven at high rates was enhanced by noradrenaline, a reduction of [K(+)]o and an elevation of [Ca(++)]o, but was reduced at low [Ca(++)]o, low [Na(+)]o and high [K(+)]o.5. The positive chronotropic response to noradrenaline was enhanced at high [Ca(++)]o, low [Na(+)]o and low [K(+)]o, but was reduced in solutions deficient in Ca(++) or rich in K(+).6. Inotropic effects of the ions and of coupled pacing were compared with those of ouabain. It is suggested that characteristic changes in the tension-rate curve seen in Na(+)-poor, K(+)-free and ouabain-containing solutions are correlated with an inhibition of active processes in the cardiac cell membrane, which affect ionic movements across it. It seems likely that mechanisms mediating adrenergic responses of the contractile tissue and the S-A node are associated with [Ca(++)]o.
journal_name
Br J Pharmacoljournal_title
British journal of pharmacologyauthors
Toda Ndoi
10.1111/j.1476-5381.1969.tb09510.xsubject
Has Abstractpub_date
1969-06-01 00:00:00pages
350-67issue
2eissn
0007-1188issn
1476-5381journal_volume
36pub_type
杂志文章abstract::1. The effects of prejunctional beta-adrenoceptor activation on electrically evoked noradrenaline (NA) and adenosine 5'-triphosphate (ATP) were studied by use of continuous amperometry and conventional intracellular recording techniques. Excitatory junction potentials (e.j.ps) were used as a measure of ATP release, an...
journal_title:British journal of pharmacology
pub_type: 杂志文章
doi:10.1038/sj.bjp.0700959
更新日期:1997-03-01 00:00:00
abstract::1. The endothelial modulation of the relaxant responses to the nitric oxide (NO) donor sodium nitroprusside (SNP) and the KATP channel opener levcromakalim (LEM) and the interactions between these agents were analysed in isolated rat aorta. 2. LEM-induced relaxation was unchanged by endothelium removal or by the prese...
journal_title:British journal of pharmacology
pub_type: 杂志文章
doi:10.1038/sj.bjp.0702924
更新日期:1999-12-01 00:00:00
abstract::Ischaemia is amongst the leading causes of death. Despite this importance, there are only a few therapeutic approaches to protect from ischaemia-reperfusion injury (IRI). In experimental studies, the amino acid glycine effectively protected from IRI. In the prevention of IRI by glycine in cells and isolated perfused o...
journal_title:British journal of pharmacology
pub_type: 杂志文章,评审
doi:10.1111/j.1476-5381.2011.01711.x
更新日期:2012-04-01 00:00:00
abstract::1. The aim of the present study was to examine whether ramipril induces delayed myocardial protection against free radical injuries ex vivo and to determine the possible role of the bradykinin B2-nitric oxide (NO) pathway, prostaglandins(PGs) and protein synthesis in this delayed adaptive response. 2. Rats were pretre...
journal_title:British journal of pharmacology
pub_type: 杂志文章
doi:10.1038/sj.bjp.0702089
更新日期:1998-10-01 00:00:00
abstract::1. The effect of in vivo desensitization to leukotriene B4 (LTB4) on eosinophil infiltration in response to recombinant C5a was examined in guinea-pig skin. 2. LTB4 (10-300 ng) and C5a (1-10 micrograms) caused a dose-dependent increase in the levels of eosinophil peroxidase activity (a measure of eosinophil infiltrati...
journal_title:British journal of pharmacology
pub_type: 杂志文章
doi:10.1111/j.1476-5381.1994.tb16182.x
更新日期:1994-09-01 00:00:00
abstract::In the clinic, low efficacy positive GABAA modulators might be preferred to high efficacy positive modulators insofar as low efficacy modulators might have comparatively less abuse and dependence liability. Drug discrimination was used to examine the behavioral effects of L-838,417 and bretazenil, two low efficacy pos...
journal_title:British journal of pharmacology
pub_type: 杂志文章
doi:10.1038/sj.bjp.0706550
更新日期:2006-02-01 00:00:00
abstract::1. Action potentials from guinea-pig single ventricular myocytes were interrupted by application of a 300 ms voltage clamp to -40 mV in order to evoke the Ca-activated tail current which is thought to be carried by Na:Ca exchange. Stimulation frequency was 1 Hz and temperature 36 degrees C. 2. The actions of ryanodine...
journal_title:British journal of pharmacology
pub_type: 杂志文章
doi:10.1111/j.1476-5381.1990.tb12721.x
更新日期:1990-10-01 00:00:00
abstract:BACKGROUND AND PURPOSE:The effect of age on the distribution of morphine and morphine-3-glucuronide (M3G) across the blood-brain barrier (BBB) was studied in a sheep model utilizing intracerebral microdialysis. The effect of neonatal asphyxia on brain drug distribution was also studied. EXPERIMENTAL APPROACH:Microdial...
journal_title:British journal of pharmacology
pub_type: 杂志文章
doi:10.1111/j.1476-5381.2009.00242.x
更新日期:2009-07-01 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:BACKGROUND AND PURPOSE:The chemokine receptor CXCR3 is implicated in a variety of clinically important diseases, notably rheumatoid arthritis and atherosclerosis. Consequently, antagonists of CXCR3 are of therapeutic interest. In this study, we set out to characterize binding sites of the specific low MW CXCR3 antagoni...
journal_title:British journal of pharmacology
pub_type: 杂志文章
doi:10.1111/bph.13027
更新日期:2015-04-01 00:00:00
abstract::1. In the presence of indomethacin (IM, 10 microM) and N omega-nitro-L- arginine (L-NOARG, 0.3 mM), acetylcholine (ACh) induces an endothelium-dependent smooth muscle hyperpolarization and relaxation in the rat isolated hepatic artery. The potassium (K) channel inhibitors, tetrabutylammonium (TBA, 1 mM) and to a lesse...
journal_title:British journal of pharmacology
pub_type: 杂志文章
doi:10.1111/j.1476-5381.1996.tb15327.x
更新日期:1996-04-01 00:00:00
abstract::1. The purpose of the present study was to develop an experimental strategy for the quantification of the cardiovascular effects of non-selective adenosine receptor ligands at the adenosine A1 and A2a receptor in vivo. 2-Chloroadenosine (CADO) was used as a model compound. 2. Three groups of normotensive conscious rat...
journal_title:British journal of pharmacology
pub_type: 杂志文章
doi:10.1111/j.1476-5381.1996.tb15412.x
更新日期:1996-05-01 00:00:00
abstract::1. The involvement of nitric oxide (NO) in the regulation of angiogenesis was examined in the in vivo system of the chorioallantoic membrane (CAM) of the chick embryo and in the matrigel tube formation assay. 2. Sodium nitroprusside (SNP) (0.37-28 nmol/disc), which releases NO spontaneously, caused a dose-dependent in...
journal_title:British journal of pharmacology
pub_type: 杂志文章
doi:10.1111/j.1476-5381.1994.tb14822.x
更新日期:1994-03-01 00:00:00
abstract::1. The hyperpolarization of the resting membrane potential, Vm, induced by isoprenaline in the lumbrical muscle fibres of the mouse, was investigated by use of intracellular microelectrodes. 2. In normal Krebs-Henseleit solution (potassium concentration: K+o = 5.7 mM, 'control'), Vm was -7.40 +/- 0.2 mV; lowering K+o ...
journal_title:British journal of pharmacology
pub_type: 杂志文章
doi:10.1111/j.1476-5381.1995.tb15940.x
更新日期:1995-12-01 00:00:00
abstract::1. This study investigated whether a single administration of a range of doses (1, 4 and 8 mg kg-1, i.p.) of paroxetine, citalopram or venlafaxine may simultaneously increase extracellular levels of 5-HT ([5-HT]ext) and noradrenaline ([NA]ext) by using in vivo microdialysis in the frontal cortex (FCx) of awake, freely...
journal_title:British journal of pharmacology
pub_type: 杂志文章
doi:10.1038/sj.bjp.0705538
更新日期:2003-11-01 00:00:00
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journal_title:British journal of pharmacology
pub_type: 杂志文章
doi:10.1111/j.1476-5381.1991.tb12311.x
更新日期:1991-05-01 00:00:00
abstract::AM-36 is a novel neuroprotective agent incorporating both antioxidant and Na(+) channel blocking actions. In cerebral ischaemia, loss of cellular ion homeostasis due to Na(+) channel activation, together with increased reactive oxygen species (ROS) production, are thought to contribute to neuronal death. Since neurona...
journal_title:British journal of pharmacology
pub_type: 杂志文章
doi:10.1038/sj.bjp.0704018
更新日期:2001-04-01 00:00:00
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journal_title:British journal of pharmacology
pub_type: 杂志文章
doi:10.1038/sj.bjp.0705961
更新日期:2004-10-01 00:00:00
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pub_type: 杂志文章
doi:10.1038/sj.bjp.0704303
更新日期:2001-10-01 00:00:00
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journal_title:British journal of pharmacology
pub_type: 社论
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更新日期:2019-01-01 00:00:00
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journal_title:British journal of pharmacology
pub_type: 临床试验,杂志文章
doi:10.1111/j.1476-5381.1970.tb10596.x
更新日期:1970-05-01 00:00:00
abstract::1. The beta-adrenoceptor blocking and calcitonin gene-related peptide (CGRP)-releasing properties of capsinolol (N-[4-(2-hydroxy-3 (isopropylamino) propoxy)-3-methoxybenzyl]-nonanamide), derived from nonivamide, were investigated under in vivo and in vitro conditions. 2. Capsinolol (0.1, 0.5, 1.0 mg kg-1, i.v.), as we...
journal_title:British journal of pharmacology
pub_type: 杂志文章
doi:10.1111/j.1476-5381.1996.tb15670.x
更新日期:1996-09-01 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::1. Nociceptin, the endogenous ORL(1) receptor agonist inhibited the motor response to electrical-field stimulation in the rat anococcygeus muscle. This effect was characterized using the peptide ligands acetyl-Arg-Tyr-Tyr-Arg-Trp-Lys-NH(2) (Ac-RYYRWK-NH(2)), acetyl-Arg-Tyr-Tyr-Arg-Ile-Lys-NH(2) (Ac-RYYRIK-NH(2)) and [...
journal_title:British journal of pharmacology
pub_type: 杂志文章
doi:10.1038/sj.bjp.0703583
更新日期:2000-09-01 00:00:00
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journal_title:British journal of pharmacology
pub_type: 杂志文章
doi:10.1038/sj.bjp.0704646
更新日期:2002-04-01 00:00:00
abstract:BACKGROUND AND PURPOSE:(-)-Englerin A (EA) is a potent cytotoxic agent against renal carcinoma cells. It achieves its effects by activation of transient receptor potential canonical (TRPC)4/TRPC1 heteromeric channels. It is also an agonist at channels formed by the related protein, TRPC5. Here, we sought an EA analogue...
journal_title:British journal of pharmacology
pub_type: 杂志文章
doi:10.1111/bph.14128
更新日期:2018-03-01 00:00:00
abstract::Tannins are a heterogeneous group of high MW, water-soluble, polyphenolic compounds, naturally present in cereals, leguminous seeds and, predominantly, in many fruits and vegetables, where they provide protection against a wide range of biotic and abiotic stressors. Tannins exert several pharmacological effects, inclu...
journal_title:British journal of pharmacology
pub_type: 杂志文章,评审
doi:10.1111/bph.13630
更新日期:2017-06-01 00:00:00
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journal_title:British journal of pharmacology
pub_type: 杂志文章
doi:10.1111/j.1476-5381.1992.tb12771.x
更新日期:1992-10-01 00:00:00
abstract::Preclinical and clinical data suggest that a modification in GABA(B) receptor expression and function may contribute to the symptoms of major depression and the response to antidepressants. This includes laboratory animal experiments demonstrating that antidepressants modify brain GABA(B) receptor expression and funct...
journal_title:British journal of pharmacology
pub_type: 杂志文章,评审
doi:10.1111/j.1476-5381.2010.01004.x
更新日期:2011-01-01 00:00:00
abstract::1. The effect of a single injection of the monoamine oxidase inhibitor, tranylcypromine, administered intravenously (20 mg/kg) or into the lateral cerebral ventricle (5-10 mg), on hypothalamic and rectal temperature, has been investigated.2. Intravenous tranylcypromine causes a significant rise in body temperature, wh...
journal_title:British journal of pharmacology
pub_type: 杂志文章
doi:10.1111/j.1476-5381.1970.tb10594.x
更新日期:1970-05-01 00:00:00