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 (1 microM and 10 microM) and caffeine (1 mM and 10 mM) on Ca-activated tail currents were investigated. 3. Exposure to 10 mM caffeine and ryanodine reduced tail currents associated with very abbreviated (12 ms duration) action potentials and greatly reduced the difference between first and steady-state tail currents at this action potential duration. These observations were interpreted in terms of suppression of Ca release from the sarcoplasmic reticulum (SR) stores. 4. Tail current decay during the voltage clamp is thought to reflect the fall in [Ca]i which accompanies muscle relaxation. Current decay is dependent on Ca extrusion via Na:Ca exchange and on Ca accumulation by the SR stores. Time constants of tail current decay were seen to decrease with increasing action potential duration. This relationship was not affected by 1 mM caffeine or 1 microM ryanodine. Ryanodine at 10 microM and 10 mM caffeine abolished this relationship and increased the time constants of current decay. An increase in the time constant of tail current decay was thought to reflect a reduction in the rate of Ca accumulation by the sarcoplasmic reticulum. 5. The actions of caffeine and ryanodine on the Ca-activated tail currents are consistent with a dose-dependent leakage of Ca from the SR Ca stores. The Ca-activated tail current appears to be a useful tool in the study of Ca homeostasis.
journal_name
Br J Pharmacoljournal_title
British journal of pharmacologyauthors
White E,Terrar DAdoi
10.1111/j.1476-5381.1990.tb12721.xsubject
Has Abstractpub_date
1990-10-01 00:00:00pages
399-405issue
2eissn
0007-1188issn
1476-5381journal_volume
101pub_type
杂志文章abstract:BACKGROUND AND PURPOSE:Excessive production of nitric oxide (NO) by inducible NO synthase (iNOS) is thought to underlie the vascular dysfunction, systemic hypotension and organ failure that characterize endotoxic shock. Plasma levels of atrial natriuretic peptide (ANP), brain natriuretic peptide (BNP) and C-type natriu...
journal_title:British journal of pharmacology
pub_type: 杂志文章
doi:10.1111/j.1476-5381.2010.00830.x
更新日期:2010-08-01 00:00:00
abstract:BACKGROUND AND PURPOSE:Sphingosine-1-phosphate (S1P) has been shown to be involved in the asthmatic disease as well in preclinical mouse experimental models of this disease. The aim of this study was to understand the mechanism(s) underlying S1P effects on the lung. EXPERIMENTAL APPROACH:BALB/c, mast cell-deficient an...
journal_title:British journal of pharmacology
pub_type: 杂志文章
doi:10.1111/bph.13033
更新日期:2015-04-01 00:00:00
abstract::1. Angiotensin-converting enzyme (ACE) inhibitors exert their cardiovascular effects not only by preventing the formation of angiotensin II (AII), but also by promoting the accumulation of bradykinin in or at the vessel wall. In addition, certain ACE inhibitors have been shown to augment the vasodilator response to br...
journal_title:British journal of pharmacology
pub_type: 杂志文章
doi:10.1038/sj.bjp.0701281
更新日期:1997-08-01 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::1. Inhibition of rat platelet aggregation by the nitric oxide (NO) donor MAHMA NONOate (Z-1-N-methyl-N-[6-(N-methylammoniohexyl)amino]diazen-1-ium-1,2-diolate) was investigated. The aims were to compare its anti-aggregatory effect with vasorelaxation, to determine the effects of the soluble guanylate cyclase inhibitor...
journal_title:British journal of pharmacology
pub_type: 杂志文章
doi:10.1038/sj.bjp.0704971
更新日期:2002-12-01 00:00:00
abstract::1. The effects of chronic oral administration of desmethylimipramine (DMI) or zimelidine (1.25 and 5 mg kg-1 twice daily for 21 days) were studied on rat whole cortical gamma-aminobutyric acidB (GABAB) binding sites. No changes in receptor affinity or number were found with either drug. 2. A subsequent study of GABAB ...
journal_title:British journal of pharmacology
pub_type: 杂志文章
doi:10.1111/j.1476-5381.1988.tb11438.x
更新日期:1988-02-01 00:00:00
abstract::Conductance increases to gamma-aminobutyric acid (GABA) were recorded in the gm6b and opener muscle of the spiny lobsters, Panulirus interruptus and P. argus. GABA-evoked responses were insensitive to picrotoxin at concentrations as high as 5 X 10(-5) M. Some blockade by picrotoxin was observed at higher concentration...
journal_title:British journal of pharmacology
pub_type: 杂志文章
doi:10.1111/j.1476-5381.1986.tb14596.x
更新日期:1986-04-01 00:00:00
abstract::We have recently shown that in polymorphonuclear leukocytes, 11-keto boswellic acids (KBAs) induce Ca2+ mobilisation and activation of mitogen-activated protein kinases (MAPK). Here we addressed the effects of BAs on central signalling pathways in human platelets and on various platelet functions. We found that beta-B...
journal_title:British journal of pharmacology
pub_type: 杂志文章
doi:10.1038/sj.bjp.0706366
更新日期:2005-10-01 00:00:00
abstract::Arthritis-associated inflammatory pain represents a serious medical problem worldwide. Current treatments for arthritic pain are not very effective and cause unwanted side effects. Resolvins, including the resolvin D and resolvin E series, are a family of novel endogenous lipid mediators derived from ω-3 polyunsaturat...
journal_title:British journal of pharmacology
pub_type: 杂志文章
doi:10.1111/j.1476-5381.2011.01348.x
更新日期:2011-09-01 00:00:00
abstract::1. Recent studies have shown antagonists at the NK1 subtype of receptor for tachykinins are antiemetics and suggested that this may result from blockade of tachykinin-mediated synaptic transmission at a central site in the emetic reflex. 2. We have used intracellular recording in vitro to study the pharmacology of tac...
journal_title:British journal of pharmacology
pub_type: 杂志文章
doi:10.1038/sj.bjp.0701482
更新日期:1997-11-01 00:00:00
abstract::The presence of functional cannabinoid CB2 receptors in the CNS has provoked considerable controversy over the past few years. Formerly considered as an exclusively peripheral receptor, it is now accepted that it is also present in limited amounts and distinct locations in the brain of several animal species, includin...
journal_title:British journal of pharmacology
pub_type: 杂志文章,评审
doi:10.1038/sj.bjp.0707505
更新日期:2008-01-01 00:00:00
abstract::1. The effect of the novel ET(A) receptor antagonist LBL 031 and other selective and mixed endothelin receptor antagonists on endothelin-1 (ET-1)-induced and lipopolysaccharide (LPS)-induced microvascular leakage was assessed in rat airways. 2. Intravenously administered ET-1 (1 nmole kg(-1)) or LPS (30 mg kg(-1)) cau...
journal_title:British journal of pharmacology
pub_type: 杂志文章
doi:10.1038/sj.bjp.0703691
更新日期:2000-11-01 00:00:00
abstract::1. Experiments were performed in anaesthetized rabbits to examine the effects of calcitonin gene-related peptide (CGRP) and the CGRP antagonist CGRP8-37 on blood flow to the medial collateral ligament of the knee joint. 2. Topical application of CGRP (10(-13) to 10(-9) mol) to the exposed external surface of eight kne...
journal_title:British journal of pharmacology
pub_type: 杂志文章
doi:10.1038/sj.bjp.0701265
更新日期:1997-08-01 00:00:00
abstract::1. Receptor phosphorylation and down-regulation by protein kinases may be a key event initiating desensitization. The present studies were designed to investigate the effect of a potent protein kinase C (PKC) activator, phorbol 12,13-dibutyrate (PDBu), on antinociception induced by intrathecal (i.t.) administration of...
journal_title:British journal of pharmacology
pub_type: 杂志文章
doi:10.1111/j.1476-5381.1996.tb15610.x
更新日期:1996-08-01 00:00:00
abstract::1. The aim of this study was to investigate whether the hypotensive effect of rat alpha-calcitonin gene-related peptide (alpha CGRP) in conscious rats is mediated by endothelium-derived nitric oxide (NO) or the opening of adenosine 5'-triphosphate (ATP)-sensitive potassium (KATP) channels. 2. Dose-mean arterial pressu...
journal_title:British journal of pharmacology
pub_type: 杂志文章
doi:10.1111/j.1476-5381.1992.tb14290.x
更新日期:1992-05-01 00:00:00
abstract::1. The electrophysiological effects of prazosin, a highly specific alpha 1-adrenoceptor antagonist, on transmembrane action potential characteristics were studied in guinea-pig papillary muscles. 2. At concentrations between 10(-6) M and 10(-5) M, prazosin produced a concentration-dependent decrease in the maximum ups...
journal_title:British journal of pharmacology
pub_type: 杂志文章
doi:10.1111/j.1476-5381.1994.tb14796.x
更新日期:1994-03-01 00:00:00
abstract::Adenosine alone at 0.1 and 1.0 mg per tracheal segment stimulated mucus secretion by 52% and 88%, respectively, compared to baseline (P less than 0.0001). The site of the potent secretagogue effect of adenosine in canine trachea was consistent with A2 activation. A2 site activation and enhanced secretion were also ind...
journal_title:British journal of pharmacology
pub_type: 杂志文章
doi:10.1111/j.1476-5381.1985.tb09435.x
更新日期:1985-09-01 00:00:00
abstract::1 Effects of dopamine and noradrenaline were compared in helically-cut strips of canine cerebral arteries. 2 Dopamine caused a greater maximal contraction than noradrenaline, although the ED50 for noradrenaline was appreciably less. The contraction induced by these amines was reversed to a relaxation by treatment with...
journal_title:British journal of pharmacology
pub_type: 杂志文章
doi:10.1111/j.1476-5381.1976.tb07700.x
更新日期:1976-09-01 00:00:00
abstract::1 Prolonged exposure (6-12 h) of rat aorta to alpha1-adrenergic receptor (alpha(1)AR) agonist phenylephrine (Phe) leads to a decrease in alpha(1)AR-mediated vasoconstriction. This reduced responsiveness to alpha(1)AR stimulation was strongly dependent on the intactness of the endothelium. 2 We examined the effect of P...
journal_title:British journal of pharmacology
pub_type: 杂志文章
doi:10.1038/sj.bjp.0706177
更新日期:2005-05-01 00:00:00
abstract::We have characterized the contribution of endothelial nitric oxide synthase (eNOS), cyclo-oxygenase (COX) and cytochrome P450 (CYP450) to the bradykinin (BK)- induced vasodilation in isolated hearts from wildtype (WT) and eNOS deficient mice (eNOS-/-). The endothelium-dependent vasodilation by bradykinin (BK, 1 microM...
journal_title:British journal of pharmacology
pub_type: 杂志文章
doi:10.1038/sj.bjp.0704472
更新日期:2002-02-01 00:00:00
abstract::The aim of this study was to evaluate the potency of YM-53601 ((E)-2-[2-fluoro-2-(quinuclidin-3-ylidene) ethoxy]-9H-carbazole monohydrochloride), a new inhibitor of squalene synthase, in reducing both plasma cholesterol and triglyceride levels, compared with 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase in...
journal_title:British journal of pharmacology
pub_type: 杂志文章
doi:10.1038/sj.bjp.0703545
更新日期:2000-09-01 00:00:00
abstract::C-C chemokine receptor-1 (CCR1) has been implicated in mediating a variety of inflammatory conditions including multiple sclerosis and organ rejection. Although originally referred to as the MIP-1alpha/RANTES receptor, CCR1 is quite promiscuous and can be activated by numerous chemokines. We used radioligand binding a...
journal_title:British journal of pharmacology
pub_type: 杂志文章
doi:10.1038/sj.bjp.0704907
更新日期:2002-11-01 00:00:00
abstract:BACKGROUND AND PURPOSE:Bleomycin (BLM), one of the most common sclerosants, is often used to treat venous malformations (VMs). The present study was designed to investigate whether endothelial mesenchymal transition (EndoMT) contributes to the therapeutic effects of BLM. EXPERIMENTAL APPROACH:Endothelial and mesenchym...
journal_title:British journal of pharmacology
pub_type: 杂志文章
doi:10.1111/bph.12355
更新日期:2013-11-01 00:00:00
abstract:BACKGROUND AND PURPOSE:We have previously shown that lipid mediators, produced by phospholipase D and C, are generated in OX(1) orexin receptor signalling with high potency, and presumably mediate some of the physiological responses to orexin. In this study, we investigated whether the ubiquitous phospholipase A(2) (PL...
journal_title:British journal of pharmacology
pub_type: 杂志文章
doi:10.1111/j.1476-5381.2009.00535.x
更新日期:2010-01-01 00:00:00
abstract::1. Therapeutic doses of colistin sulphomethate sodium B.P. (Colomycin), pento-N sulphomethylpolymyxin B sodium (Thiosporin) and ampicillin B.P. (Penbritin) as well as normal saline have been given to volunteers with normal kidney function.2. A blind crossover technique was used and the effects of the compounds on bloo...
journal_title:British journal of pharmacology
pub_type: 临床试验,杂志文章,随机对照试验
doi:10.1111/j.1476-5381.1969.tb09545.x
更新日期:1969-09-01 00:00:00
abstract:BACKGROUND AND PURPOSE:Saponins isolated from Panax notoginseng (Burk.) F.H. Chen have been shown to relieve thrombogenesis and facilitate haemostasis. However, it is not known which saponin accounts for this haemostatic effect. Hence, in the present study we aimed to identify which saponins contribute to its haemostat...
journal_title:British journal of pharmacology
pub_type: 杂志文章
doi:10.1111/bph.12435
更新日期:2014-01-01 00:00:00
abstract::1. Recent studies demonstrated that inhibition or genetic inactivation of the enzyme poly (ADP-ribose) polymerase (PARP) is beneficial in myocardial reperfusion injury. PARP activation in the reperfused myocardium has been assumed, but not directly demonstrated. Furthermore, the issue whether pharmacological PARP inhi...
journal_title:British journal of pharmacology
pub_type: 杂志文章
doi:10.1038/sj.bjp.0704185
更新日期:2001-08-01 00:00:00
abstract::1. Heterologous desensitization or intermolecular cross-talk plays a critical role in regulating intracellular signalling by diverse members of the G-protein-coupled receptor superfamily. We have previously established that the alpha and beta isoforms of the human thromboxane A(2) receptor (TP) undergo differential de...
journal_title:British journal of pharmacology
pub_type: 杂志文章
doi:10.1038/sj.bjp.0705695
更新日期:2004-05-01 00:00:00
abstract::1. Skins of the lizard Anolis carolinensis darken in vitro in response to melanophore stimulating hormone (MSH), a peptide hormone, as well as to catecholamines. These hormones darken Anolis skins by dispersing the sub-cellular organelle, the melanosome, out into the dendritic processes of the dermal melanophores.2. D...
journal_title:British journal of pharmacology
pub_type: 杂志文章
doi:10.1111/j.1476-5381.1970.tb09565.x
更新日期:1970-05-01 00:00:00
abstract:BACKGROUND AND PURPOSE:In addition to typical GPCR kinase (GRK)-/β-arrestin-dependent internalization, dopamine D3 receptor employed an additional GRK-independent sequestration pathway. In this study, we investigated the molecular mechanism of this novel sequestration pathway. EXPERIMENTAL APPROACH:Radioligand binding...
journal_title:British journal of pharmacology
pub_type: 杂志文章
doi:10.1111/bph.12357
更新日期:2013-11-01 00:00:00