Abstract：
:1. Pharmacological studies of alpha7 nicotinic acetylcholine receptors are confounded by the fact that rapid desensitization to high agonist concentration causes alpha7 peak responses to occur well in advance of complete solution exchange. For this reason, peak currents are an invalid measure of response to applied agonist concentrations. We show that results comparable to those that have been corrected for instantaneous concentration are obtained if net charge is used as the measure of receptor response. 2. Dose response curves obtained with these methods indicate that alpha7 receptors are approximately 10 fold more sensitive to agonist than previously reported. The agonists, ACh, choline, cytisine, GTS-21, 4OH-GTS-21 and 4-MeO-CA have the same rank order potency for both human and rat receptors: 4-MeO-CA > 4OH-GTS-21 > GTS-21 > cytisine > ACh > choline. However, differences in efficacy exist between rat and human receptors. GTS-21 is more efficacious for rat than human alpha7 receptors and cytosine more efficacious for human than rat alpha7 receptors. 3. Choline is the least potent agonist for both human and rat alpha7, with a potency approximately 10 fold lower than that of ACh. While the EC50 for the activation of alpha7 receptors by choline (400-500 microM) is outside the normal physiological range (10-100 microM), choline can nonetheless produce detectable levels of channel activation in the physiological concentration range. Since these concentrations are relatively non-desensitizing, the contribution of choline-activated alpha7 receptor current may play a significant role in the regulation of calcium homeostasis in alpha7-expressing neurons.
journal_name
Br J Pharmacoljournal_title
British journal of pharmacologyauthors
Papke RL,Porter Papke JKdoi
10.1038/sj.bjp.0704833subject
Has Abstractpub_date
2002-09-01 00:00:00pages
49-61issue
1eissn
0007-1188issn
1476-5381journal_volume
137pub_type
杂志文章abstract：:1. The experiment investigated the effects of psychotropic drugs on enzymes in vitro.2. Chlorpromazine inhibits mitochondrial malate dehydrogenase in concentrations of 1.4x10(-4)M and above. No effect was observed below this concentration.3. A sharp inflection in the [unk]/drug plot was also seen with chlorpromazine (...
journal_title：British journal of pharmacology
pub_type： 杂志文章
doi：10.1111/j.1476-5381.1969.tb10582.x
更新日期：1969-10-01 00:00:00
abstract：BACKGROUND AND PURPOSE:The endocannabinoid system and the cannabinoid CB(1) receptor have been identified in human sperm, and it is well known that endocannabinoids have pronounced adverse effects on male and female reproduction. In order to elucidate further the pathophysiological role of the endocannabinoid system in...
journal_title：British journal of pharmacology
pub_type： 杂志文章
doi：10.1111/j.1476-5381.2009.00570.x
更新日期：2010-02-01 00:00:00
abstract：:N-methyl-d-aspartate (NMDA) receptors have been demonstrated to be a pivotal target for ethanol action. The present study examined the actions of acute ethanol exposure on NMDA-induced responses and the acute tolerance to ethanol actions in rat sympathetic preganglionic neurons (SPNs) in vitro and in vivo. NMDA (50 mi...
journal_title：British journal of pharmacology
pub_type： 杂志文章
doi：10.1038/sj.bjp.0705512
更新日期：2003-11-01 00:00:00
abstract：:1. Effects of oestradiol on the electrical and mechanical properties of the rabbit basilar artery were investigated by use of microelectrode, patch-clamp and isometric tension recording methods. 2. Oestradiol (10 nM-100 microM) relaxed arterial tissue pre-contracted by excess [K]o solution (30 mM) in a concentration-d...
journal_title：British journal of pharmacology
pub_type： 杂志文章
doi：10.1111/j.1476-5381.1996.tb15198.x
更新日期：1996-01-01 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 studied the effects of the weak bases chloroquine, NH4Cl and amantadine on the handling of certain cardiac glycosides by HeLa cells. When these weak bases are applied acutely to HeLa cells they have only minor effects on the binding of cardiac glycosides to the sodium pumps and on the recovery of pump function...
journal_title：British journal of pharmacology
pub_type： 杂志文章
doi：10.1111/j.1476-5381.1983.tb10532.x
更新日期：1983-08-01 00:00:00
abstract：:1. The effect of the potassium channel openers, NIP-121 and cromakalim, on agonist-induced relaxation of the guinea-pig isolated trachea was investigated and the results were compared with those in the epithelium-denuded trachea. 2. Tracheal strips were incubated with a potassium channel opener or vehicle for 30 min i...
journal_title：British journal of pharmacology
pub_type： 杂志文章
doi：10.1111/j.1476-5381.1992.tb13416.x
更新日期：1992-12-01 00:00:00
abstract：:1. The mechanisms by which nicorandil causes relaxation of rat isolated small mesenteric arteries mounted on a Mulvany myograph was investigated by use of a combination of putatively mechanism-specific antagonists. 2. In arteries precontracted by the thromboxane-mimetic, U46619, the EC50 for cromakalim and levcromakal...
journal_title：British journal of pharmacology
pub_type： 杂志文章
doi：10.1111/j.1476-5381.1996.tb16071.x
更新日期：1996-12-01 00:00:00
abstract：:Despite its long-standing reputation as a foul smelling and toxic gas that is associated with the decay of biological matter,hydrogen sulphide (H2S) has emerged as an important regulator of cardiovascular homoeostasis. H2S promotes a number of cellular signals that regulate metabolism, cardiac function and cell surviv...
journal_title：British journal of pharmacology
pub_type： 杂志文章
doi：10.1038/bjp.2008.359
更新日期：2008-11-01 00:00:00
abstract：:1. Experiments were designed to investigate the effects of the inducible nitric oxide synthase (iNOS) stimulator, lipopolysaccharide (LPS), on noradrenaline (NA) responses and on NOS activity and its expression in intact mesenteric resistance arteries (MRAs) from Wistar Kyoto (WKY) and spontaneously hypertensive (SHR)...
journal_title：British journal of pharmacology
pub_type： 杂志文章
doi：10.1038/sj.bjp.0703552
更新日期：2000-09-01 00:00:00
abstract：:1. The influence of angiotensin II (AII) on resting blood pressure and on sympathetic nerve-mediated pressor responses in the pithed rat was investigated either by inhibiting the renin-angiotensin system or by infusing AII. 2. Plasma AII levels in the pithed rat were approximately 20 fold higher than in normotensive r...
journal_title：British journal of pharmacology
pub_type： 杂志文章
doi：10.1111/j.1476-5381.1988.tb11759.x
更新日期：1988-12-01 00:00:00
abstract：:1 The effect of 5-hydroxytryptamine (5-HT) on acid secretion by a rat isolated stomach preparation has been studied. 2 5-HT at 10(-5)M in the serosal bathing fluid produced significant inhibition of the acid secretory responses to histamine, pentagastrin and isoprenaline but was without effect on basal secretion or th...
journal_title：British journal of pharmacology
pub_type： 杂志文章
doi：10.1111/j.1476-5381.1983.tb09371.x
更新日期：1983-01-01 00:00:00
abstract：BACKGROUND AND PURPOSE:Tumour cell-induced platelet aggregation (TCIPA) facilitates cancer cell invasion, angiogenesis and the formation of metastatic foci. TCIPA can be modulated by pharmacological inhibitors of MMP-2 and ADP; however, the COX inhibitor aspirin did not prevent TCIPA. In this study, we have tested the ...
journal_title：British journal of pharmacology
pub_type： 杂志文章
doi：10.1111/j.1476-5381.2011.01794.x
更新日期：2012-06-01 00:00:00
abstract：:The detrimental actions of leptin on cardiovascular function are well established. Smith et al. report the novel finding of a reduction of infarct size by exogenous leptin when given at reperfusion. The involvement of the reperfusion injury salvage kinase (RISK) pathway in such reduction of infarct size and its relati...
journal_title：British journal of pharmacology
pub_type： 评论,杂志文章
doi：10.1038/sj.bjp.0706833
更新日期：2006-09-01 00:00:00
abstract：:1. We have investigated the in vitro interaction between chloride ions and endothelium as revealed by alterations in vascular contractility and smooth muscle cell membrane potential in isolated pulmonary arteries from Dahl salt-resistant normotensive and salt-sensitive hypertensive rats. 2. Exposure to nitro-l-arginin...
journal_title：British journal of pharmacology
pub_type： 杂志文章
doi：10.1038/sj.bjp.0705703
更新日期：2004-03-01 00:00:00
abstract：:The binding of DL-[3,4-3H] 2-amino-4-phosphonobutyric acid DL[3H]-APB to rat whole brain synaptic membranes was investigated. Binding was linear with membrane protein concentration, and optimal at physiological pH and temperature. The association rate was rapid, achieving equilibrium within 10 min. Prolonged incubatio...
journal_title：British journal of pharmacology
pub_type： 杂志文章
doi：10.1111/j.1476-5381.1983.tb10041.x
更新日期：1983-10-01 00:00:00
abstract：:Pulmonary arterial hypertension (PAH) is a complex disease characterized by elevated pulmonary arterial pressure, pulmonary vascular remodelling and occlusive pulmonary vascular lesions, leading to right heart failure. Evidence from recent epidemiological studies suggests the influence of gender on the development of ...
journal_title：British journal of pharmacology
pub_type： 杂志文章,评审
doi：10.1111/bph.12281
更新日期：2014-02-01 00:00:00
abstract：:1. Insulin antibodies were induced in young guinea-pigs of both sexes weighing 300-400 g and housed in a room maintained at 28 degrees C+/-2 degrees C, by subcutaneous injection of 2 ml of freshly prepared insulin antigen emulsion between the shoulders once every month.2. To estimate the titre of serum antibody the se...
journal_title：British journal of pharmacology
pub_type： 杂志文章
doi：10.1111/j.1476-5381.1971.tb07087.x
更新日期：1971-05-01 00:00:00
abstract：:1. Tyrosine kinases have been proposed as regulators of voltage-operated calcium channels. The effects of a range of structurally different inhibitors of protein tyrosine kinases (PTK) were examined on voltage-operated calcium channel currents (I(Ba)) and pp60(c-src) kinase (c-src) activity in vitro. 2. I(Ba) was meas...
journal_title：British journal of pharmacology
pub_type： 杂志文章
doi：10.1038/sj.bjp.0703186
更新日期：2000-04-01 00:00:00
abstract：:This paper is intended to assist pharmacologists to make the most of statistical analysis and avoid common errors. A scenario, in which an experimenter performed an experiment in two separate stages, combined the control groups for analysis and found some surprising results, is presented. The consequences of combined ...
journal_title：British journal of pharmacology
pub_type： 杂志文章,评审
doi：10.1038/bjp.2008.350
更新日期：2008-11-01 00:00:00
abstract：:1. We have investigated the effects of RP 73401, a novel, potent and highly selective cyclic nucleotide phosphodiesterase (PDE) type IV inhibitor, in guinea-pig and rat models of bronchoconstriction and allergic inflammation. In some models, the effects of RP 73401 have been compared with those of the standard PDE typ...
journal_title：British journal of pharmacology
pub_type： 杂志文章
doi：10.1111/j.1476-5381.1994.tb17156.x
更新日期：1994-12-01 00:00:00
abstract：:1. The effects of an intrathecally administered benzodiazepine receptor (BZR) agonist (midazolam, up to 50 micrograms), antagonist (flumazenil, Ro 15-1788, 5 micrograms) and inverse agonist (Ro 19-4603, 15 micrograms) on nociception and on morphine-induced antinociception were studied in rats. 2. By themselves, none o...
journal_title：British journal of pharmacology
pub_type： 杂志文章
doi：10.1111/j.1476-5381.1988.tb11486.x
更新日期：1988-04-01 00:00:00
abstract：:1. In order to define the electrophysiological mechanism(s) responsible for bradykinin (BK)-induced positive inotropic and chronotropic responses in isolated guinea-pig atria, effects of BK on the membrane currents were examined in isolated atrial cells using patch clamp techniques. 2. BK (0.1-1000 nM) increased the L...
journal_title：British journal of pharmacology
pub_type： 杂志文章
doi：10.1038/sj.bjp.0702060
更新日期：1998-09-01 00:00:00
abstract：:1. The effects of some rapidly metabolized sympathomimetic amines, such as beta-phenylethylamine and p-tyramine, in eliciting hypertensive responses to reserpine in the anaesthetized rat, have been studied.2. Retardation of metabolism, by pretreatment with the monoamineoxidase inhibitors iproniazid or phenelzine, caus...
journal_title：British journal of pharmacology
pub_type： 杂志文章
doi：10.1111/j.1476-5381.1972.tb07256.x
更新日期：1972-02-01 00:00:00
abstract：:1 A rat isolated gastric mucosal preparation was used to monitor histamine output and acid secretion during stimulation by different secretagogues. 2 In non-stimulated preparations, spontaneous histamine output decreased over 450 min. 3 Stimulation of secretion with 4 (5)-methylhistamine or dibutyryl cyclic adenosine ...
journal_title：British journal of pharmacology
pub_type： 杂志文章
doi：10.1111/j.1476-5381.1982.tb09190.x
更新日期：1982-05-01 00:00:00
abstract：:The mechanism of action of prostacyclin (PGI2) on isolated segments of guinea-pig terminal ileum was studied by recording the changes in isometric tension. In these preparations PGI2 (1 nM-1 microM) caused a concentration-dependent increase in muscle tension. This effect was rapid and short-lasting. PGI2-induced contr...
journal_title：British journal of pharmacology
pub_type： 杂志文章
doi：10.1111/j.1476-5381.1983.tb10031.x
更新日期：1983-10-01 00:00:00
abstract：:1 Noradrenaline and clonidine were applied by microiontophoresis to single neurones in the cerebral cortex and medullary reticular formation of anaesthetized rats.2 Of a total of 247 neurones studied, 79% of medullary units and 60% of cortical units responded in the same manner to both noradrenaline and clonidine. The...
journal_title：British journal of pharmacology
pub_type： 杂志文章
doi：10.1111/j.1476-5381.1974.tb10670.x
更新日期：1974-07-01 00:00:00
abstract：BACKGROUND AND PURPOSE:Sublesional osteoporosis predisposes individuals with spinal cord injury (SCI) to an increased risk of low-trauma fracture. The aim of the present work was to investigate the effect of treatment with resveratrol (RES) on sublesional bone loss in spinal cord-injured rats. EXPERIMENTAL APPROACH:Co...
journal_title：British journal of pharmacology
pub_type： 杂志文章
doi：10.1111/bph.12301
更新日期：2013-10-01 00:00:00
abstract：:1. Prostaglandin E2 (PGE2) relaxes circular smooth muscle of the rabbit isolated jugular vein at very low concentrations (mean pIC50 against histamine-induced contraction = 9.34). This effect is not blocked by the EP1-receptor antagonist, AH 6809 (2 microM). 2. From a group of prostaglandin E analogues examined, 16,16...
journal_title：British journal of pharmacology
pub_type： 杂志文章
doi：10.1111/j.1476-5381.1992.tb09063.x
更新日期：1992-04-01 00:00:00
abstract：:1. The present experiments were designed to investigate the mechanisms causing intimal hyperplasia in connection with the impaired synergism between prostaglandin I2 (PGI2) and nitric oxide (NO) in human uterine arteries (UAs). 2. In order to assess the magnitude of intimal hyperplasia, the intima:media ratio (%) was ...
journal_title：British journal of pharmacology
pub_type： 杂志文章
doi：10.1111/j.1476-5381.1996.tb15779.x
更新日期：1996-11-01 00:00:00
