Abstract:
:1. The subtype of alpha1-adrenoceptor mediating contractions to phenylephrine of the rat thoracic aorta, mesenteric artery and pulmonary artery were investigated by use of antagonists which show selectivity between the cloned alpha1-adrenoceptor subtypes in binding studies. 2. Cumulative concentration-contraction curves for phenylephrine were competitively antagonized in the rat thoracic aorta by prazosin (pA2 9.9), WB4101 (pA2 9.6), 5-methylurapidil (pA2 8.1), benoxathian (pA2 9.2) and indoramin (pA2 7.4). These compounds were also competitive antagonists in the mesenteric and pulmonary arteries (except for 5-methylurapidil in the pulmonary artery), (prazosin pA2 9.9 and 9.7; WB4101 pA2 9.8 and 9.6; 5-methylurapidil pA2 7.9 and pK(B) estimate 8.0; benoxathian pA2 8.8 and 9.3; indoramin pA2 7.2 and 7.5, respectively). 3. RS 17053 was not a competitive antagonist in any blood vessel as Schild plot slopes were greater than unity. The pK(B) estimates for RS 17053 were 7.1 in aorta, 7.0 in the mesenteric artery and 7.7 in the pulmonary artery. 4. The alpha1D-subtype selective antagonist BMY 7378 appeared to be non-competitive with shallow Schild plot slopes. The data were better fitted with two lines in all tissues, with Schild plot slopes that were no longer different from unity, except in the pulmonary artery. The higher affinity site for BMY 7378 in the aorta had a pA2 of 9.0, while it was 8.8 and 8.9 in the mesenteric and pulmonary arteries, respectively. 5. MDL73005EF acted in a non-competitive manner in all three blood vessels, with shallow Schild plot slopes. The pK(B) estimates for MDL73005EF were 8.4 in aorta, 7.5 in the mesenteric artery and 8.0 in the pulmonary artery. 6. In all three blood vessels the functionally determined antagonist affinity estimates correlated best with published pKi values for their displacement of [3H]-prazosin binding on membranes expressing cloned alpha1d-adrenoceptors compared with alpha1a- or alpha1b-adrenoceptors. The antagonist affinity estimates in the aorta, mesenteric and pulmonary arteries correlated highly with their previously published pA2 values in rat aorta (alpha1D) and less well with those for alpha1A- and alpha1B-adrenoceptors mediating contraction of the rat epididymal vas deferens and rat spleen, respectively. 7. The results of this study suggest that the contraction to phenylephrine of the rat thoracic aorta, mesenteric artery and pulmonary artery are mediated in part via the alpha1D-subtype of adrenoceptor. The data for both BMY 7378 and MDL73005EF in all three blood vessels are consistent with receptor heterogeneity. However, the identity of the second site is unclear.
journal_name
Br J Pharmacoljournal_title
British journal of pharmacologyauthors
Hussain MB,Marshall Idoi
10.1038/sj.bjp.0701461subject
Has Abstractpub_date
1997-11-01 00:00:00pages
849-58issue
5eissn
0007-1188issn
1476-5381journal_volume
122pub_type
杂志文章abstract::1. Previous studies had shown that adenosine and adenine nucleotides including adenosine 5'-triphosphate (ATP) caused contraction of the rat colon muscularis mucosae via P1 and P2Y-purinoceptors respectively, and that the stable ATP analogue adenylyl 5'-(beta,gama- methylene)diphosphonate (AMPPCP) had an unexpected di...
journal_title:British journal of pharmacology
pub_type: 杂志文章
doi:10.1111/j.1476-5381.1992.tb14265.x
更新日期:1992-02-01 00:00:00
abstract::The effect of trimetazidine (TMZ), an anti-anginal drug, on the mechanical response of the guinea-pig ductus arteriosus placed under conditions of mild hypoxia (PO2 approximately equal to 75 mmHg) was investigated. When the PO2 of the bathing solution was 75 mmHg, TMZ caused a dose-dependent increase in tension. The m...
journal_title:British journal of pharmacology
pub_type: 杂志文章
doi:10.1111/j.1476-5381.1985.tb12936.x
更新日期:1985-02-01 00:00:00
abstract::1. The dihydropyridine calcium channel activator, Bay K 8644, is believed to increase mean arterial blood pressure in several animal models, as a result of direct activation of vascular smooth muscle cells by increasing calcium influx through the voltage-dependent calcium channels. The purpose of the current study was...
journal_title:British journal of pharmacology
pub_type: 杂志文章
doi:10.1111/j.1476-5381.1988.tb11490.x
更新日期:1988-04-01 00:00:00
abstract::1. Incubation of bovine adrenal chromaffin cells with veratridine (10-100 microM) during 24 h, caused a concentration-dependent release of the cytosolic lactate dehydrogenase (LDH) into the bathing medium, an indicator of cell death. Lubeluzole or its R(-) enantiomer, R91154, did not enhance LDH release. Both lubeluzo...
journal_title:British journal of pharmacology
pub_type: 杂志文章
doi:10.1038/sj.bjp.0701955
更新日期:1998-07-01 00:00:00
abstract::Chlorisondamine (CHL) blocks behavioural responses to nicotine for several weeks or months in rats. Persistent blockade has also been demonstrated ex vivo, in assays of nicotine-evoked striatal dopamine release. Central administration of [3H]-CHL leads to long-term retention of radiolabel in nigrostriatal dopaminergic...
journal_title:British journal of pharmacology
pub_type: 杂志文章
doi:10.1038/sj.bjp.0702215
更新日期:1998-11-01 00:00:00
abstract::The concentration of intracellular free Ca2+ ( [Ca2+]i) in human blood platelets was measured by use of the fluorescent probe quin-2. 5-Hydroxytryptamine (5-HT) caused a rapid increase of [Ca2+]i in the presence or absence of Ca2+ in the medium. The [Ca2+]i-rise was less marked in the absence of Ca2+ and could be anta...
journal_title:British journal of pharmacology
pub_type: 杂志文章
doi:10.1111/j.1476-5381.1985.tb12939.x
更新日期:1985-02-01 00:00:00
abstract::1. The effect of synthetic tachykinin selective receptor agonists was studied on the growth of cultured human skin fibroblasts (HF). 2. Human fibroblasts were grown in serum-free conditions in the presence of natural tachykinins (substance P and neurokinin A) and of three synthetic agonists, [beta-Ala4, Sar9, Met(O2)1...
journal_title:British journal of pharmacology
pub_type: 杂志文章
doi:10.1111/j.1476-5381.1990.tb12043.x
更新日期:1990-05-01 00:00:00
abstract::1. Depolarization of rat cerebral cortical slices, prelabelled with [3H]-histidine, in high potassium (40 mM KCl) medium stimulated the release of [3H]-histamine. The K+-evoked release of [3H]-histamine was attenuated by incubation in calcium-free medium and prevented by prior incubation of brain slices with the selec...
journal_title:British journal of pharmacology
pub_type: 杂志文章
doi:10.1111/j.1476-5381.1988.tb11758.x
更新日期:1988-12-01 00:00:00
abstract:BACKGROUND AND PURPOSE:Cloxyquin (5-cloroquinolin-8-ol) has been described as an activator of TRESK (K2P 18.1, TWIK-related spinal cord K+ channel) background potassium channel. We have examined the specificity of the drug by testing several K2P channels. We have investigated the mechanism of cloxyquin-mediated TRESK a...
journal_title:British journal of pharmacology
pub_type: 杂志文章
doi:10.1111/bph.13821
更新日期:2017-07-01 00:00:00
abstract::The binding of a series of amide derivatives of methotrexate to Lactobacillus casei dihydrofolate reductase has been studied by inhibition constant measurements and by 1H n.m.r. spectroscopy. Amide modification of the alpha-carboxylate of methotrexate was found to prevent interaction of the gamma-carboxylate with the ...
journal_title:British journal of pharmacology
pub_type: 杂志文章
doi:10.1111/j.1476-5381.1984.tb10080.x
更新日期:1984-02-01 00:00:00
abstract:BACKGROUND AND PURPOSE:Gain of function mutations in TRPC6 channels can cause autosomal dominant forms of focal segmental glomerulosclerosis (FSGS). Validated inhibitors of TRPC6 channels that are biologically active on FSGS-related TRPC6 mutants are eagerly sought. EXPERIMENTAL APPROACH:We synthesized new TRPC6-inhib...
journal_title:British journal of pharmacology
pub_type: 杂志文章
doi:10.1111/bph.13977
更新日期:2017-11-01 00:00:00
abstract::1. The ratio of the content of vasopressin to that of oxytocin (V/O ratio) was estimated in the supraoptic nucleus (SON), paraventricular nucleus (PVN) and posterior pituitary gland (PIT) of guinea-pigs.2. Extracts were assayed for antidiuretic activity to estimate vasopressin and for milk-ejecting activity to estimat...
journal_title:British journal of pharmacology
pub_type: 杂志文章
doi:10.1111/j.1476-5381.1973.tb06912.x
更新日期:1973-06-01 00:00:00
abstract::1. A technique for the close-arterial administration of substances to the rat stomach in vivo has been developed. 2. Intra-arterial infusion of platelet-activating factor (Paf, 10-50 ng kg-1 min-1 for 10 min) induced macroscopically assessed damage in the corpus mucosa, characterized as vasocongestion and necrosis. 3....
journal_title:British journal of pharmacology
pub_type: 杂志文章
doi:10.1111/j.1476-5381.1988.tb11425.x
更新日期:1988-01-01 00:00:00
abstract:BACKGROUND AND PURPOSE:While selective, bitter tasting, TAS2R agonists can relax agonist-contracted airway smooth muscle (ASM), their mechanism of action is unclear. However, ASM contraction is regulated by Ca²⁺ signalling and Ca²⁺ sensitivity. We have therefore investigated how the TAS2R10 agonists chloroquine, quinin...
journal_title:British journal of pharmacology
pub_type: 杂志文章
doi:10.1111/bph.12460
更新日期:2014-02-01 00:00:00
abstract:BACKGROUND AND PURPOSE:Injury to the lung parenchyma is a constitutional feature shared by many lung diseases. The protein, phosphatase and tensin homologue deleted on chromosome Ten (PTEN) is a major suppressor of phosphoinositide-3 kinase/Akt signalling, a vital survival pathway in lung parenchymal cells. Based on th...
journal_title:British journal of pharmacology
pub_type: 杂志文章
doi:10.1111/j.1476-5381.2008.00020.x
更新日期:2009-01-01 00:00:00
abstract::1. A murine macrophage cell line, J774, expressed nitric oxide (NO) synthase activity in response to interferon-gamma (IFN-gamma, 10 u ml-1) plus lipopolysaccharide (LPS, 10 ng ml-1). The enzyme activity was first detectable 6 h after incubation, peaked at 12 h and became undetectable after 48 h. 2. The decline in the...
journal_title:British journal of pharmacology
pub_type: 杂志文章
doi:10.1111/j.1476-5381.1993.tb12886.x
更新日期:1993-03-01 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::1. Chronic treatment with low doses of the selective monoamine oxidase (MAO) type B inhibitors selegiline [(-)-deprenyl] and rasagiline, causes elevation in extracellular level of 3,4-dihydroxyphenylethylamine (dopamine) in the rat striatum in vivo (Lamensdorf et al., 1996). The present study was carried out to determ...
journal_title:British journal of pharmacology
pub_type: 杂志文章
doi:10.1038/sj.bjp.0702389
更新日期:1999-02-01 00:00:00
abstract::1. The sensitivity of the guinea-pig vas deferens to noradrenaline, histamine, methylfurmethide and potassium was examined in vitro following decentralization and reserpine treatment.2. One day after decentralization or administration of reserpine (1.0 mg/kg daily) the sensitivity of the vas deferens was not increased...
journal_title:British journal of pharmacology
pub_type: 杂志文章
doi:10.1111/j.1476-5381.1970.tb09560.x
更新日期:1970-05-01 00:00:00
abstract::Sodium transport has been measured in the isolated epithelium from colons of male Sprague-Dawley rats. Sodium transport in colons was induced by pretreating the animals with dexamethasone (6 mg kg-1) which caused the appearance of an amiloride-sensitive short circuit current within a few hours. Forskolin, a diterpene,...
journal_title:British journal of pharmacology
pub_type: 杂志文章
doi:10.1111/j.1476-5381.1983.tb10017.x
更新日期:1983-07-01 00:00:00
abstract::1. Tachycardia and bronchodilatation were produced by intravenous dimethylphenylpiperazinium iodide (DMPP) in the spinal or pithed cat. Responses other than those involving beta-adrenoceptors were minimized by appropriate blocking agents.2. With intact adrenals, both the tachycardia and bronchodilatation with 10 mug/k...
journal_title:British journal of pharmacology
pub_type: 杂志文章
doi:10.1111/j.1476-5381.1973.tb08256.x
更新日期:1973-08-01 00:00:00
abstract::1. We have investigated the mechanism of smooth muscle contraction evoked by activation of 5-HT1-like receptors in dog isolated saphenous vein. 2. In the presence of the 5-HT2 receptor antagonist, ritanserin (0.1 microM), concentration-effect curves (10 nM-300 microM) for 5-hydroxytryptamine (5-HT)-induced smooth musc...
journal_title:British journal of pharmacology
pub_type: 杂志文章
doi:10.1111/j.1476-5381.1992.tb09026.x
更新日期:1992-03-01 00:00:00
abstract::1 Tissue was taken from guinea-pigs that had been injected with guanethidine (100 mg/kg, i.p.) 24 h before they were killed, and from paired control animals.2 Pretreatment with guanethidine caused a significant, substantial, and sometimes complete reduction of the nerve-mediated contractions of the vas deferens. There...
journal_title:British journal of pharmacology
pub_type: 杂志文章
doi:10.1111/j.1476-5381.1974.tb09593.x
更新日期:1974-01-01 00:00:00
abstract::[3H]-guanfacine (N-amidino-2-(2,6-dichloro 3[3H] phenyl) acetamide hydrochloride; 24.2 Ci/mmol) has been used as a radioligand in homogenates of rat cerebral cortex. Specific binding of [3H]-guanfacine was linear with respect to tissue concentration (2.5-15 mg/ml), saturable and not markedly affected in the pH range 6...
journal_title:British journal of pharmacology
pub_type: 杂志文章
doi:10.1111/j.1476-5381.1982.tb08801.x
更新日期:1982-02-01 00:00:00
abstract::1. The effects of purinergic stimulation on action potential, force of contraction, 86Rb efflux and 45Ca uptake were investigated in guinea-pig left atria. 2. Adenosine exerted a negative inotropic effect which was antagonized by adenosine deaminase but enhanced by dipyridamole. 3. The negative inotropic effect of ade...
journal_title:British journal of pharmacology
pub_type: 杂志文章
doi:10.1111/j.1476-5381.1989.tb12577.x
更新日期:1989-08-01 00:00:00
abstract:BACKGROUND AND PURPOSE:Our team previously demonstrated that diabetes induces a deterioration in vascular dynamics, in parallel with the enhanced formation of advanced glycation end products. The aim of this study was to determine whether prevention of the arterial stiffening by pyridoxamine in diabetes is associated w...
journal_title:British journal of pharmacology
pub_type: 杂志文章
doi:10.1111/j.1476-5381.2009.00309.x
更新日期:2009-08-01 00:00:00
abstract::1. The effects of 8-bromoguanosine 3':5'-cyclic monophosphate (8-bromo-cyclic GMP) on phenylephrine-induced contractions and phosphatidylinositol (PI) hydrolysis were investigated in rat isolated caudal artery. The effects of the nucleotide were compared to those of felodipine, a dihydropyridine Ca2+ channel antagonis...
journal_title:British journal of pharmacology
pub_type: 杂志文章
doi:10.1111/j.1476-5381.1995.tb16394.x
更新日期:1995-09-01 00:00:00
abstract::The consumption of green tea (Camellia sinensis) has been shown to have many physiological and pharmacological health benefits. In the past two decades several studies have reported that epigallocatechin-3-gallate (EGCG), the main constituent of green tea, has anti-infective properties. Antiviral activities of EGCG wi...
journal_title:British journal of pharmacology
pub_type: 杂志文章,评审
doi:10.1111/bph.12009
更新日期:2013-03-01 00:00:00
abstract:BACKGROUND AND PURPOSE:The development of subtype-selective ligands to inhibit voltage-sensitive sodium channels (VSSCs) has been attempted with the aim of developing therapeutic compounds. Tetrodotoxin (TTX) is a toxin from pufferfish that strongly inhibits VSSCs. Many TTX analogues have been identified from marine an...
journal_title:British journal of pharmacology
pub_type: 杂志文章
doi:10.1111/bph.13985
更新日期:2017-11-01 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