bluuebunny/crossref_metadata_2025_split huggingface dataset:
Nitric oxide (NO) modulation of PAF‐induced cardiopulmonary action: interaction between NO synthase and cyclo‐oxygenase‐2 pathways
Authors: Fabi Fulvia , Calabrese Roberto , Stati Tonino , Del Basso Paola 
Published: January 2005

To further investigate into the mechanisms of PAF‐induced cardiopulmonary actions, we examined the effects of the nitric oxide synthase (NOS) inhibitor L‐Nω‐nitro‐L‐arginine (L‐NNA), of the specific cyclooxygenase‐2 (COX‐2) inhibitor NS 398, and of the combined presence of both COX and NOS inhibitors on the PAF responses in the heart lung preparation of guinea‐pig (HLP).
In HLPs perfused with homologous blood, dose‐response curves for the haemodynamic and bronchial effects of PAF (1 – 32 ng) were carried out in the absence or presence of L‐NNA (200 μM). L‐NNA caused an increase in the resting pulmonary arterial pressure (PAP) without affecting the other basal values, and strongly potentiated the bronchoconstriction and pulmonary hypertension elicited by PAF. An enhancement of the PAF‐induced actions on right atrial pressure (RAP) and cardiac output (CO) was also observed. All the effects of L‐NNA were antagonized by L‐arginine (2 mM).
The presence of L‐NNA in the perfusing blood of HLPs failed to affect the pulmonary hypertensive and bronchoconstrictor responses induced by the thromboxane A2 mimetic U46619 (0.05 – 1.6 μg), 5‐hydroxytryptamine (0.1 – 1.6 μg), and histamine (0.1 – 1.6 μg), thus suggesting that these PAF secondary mediators are not responsible for the hyper‐responsiveness to PAF induced by L‐NNA.
Blocking COX‐2 pathway with NS 398 (15 – 30 μM) did not alter the cardiopulmonary resting variables. However, a reduction of the PAF‐mediated pulmonary hypertension, but not of bronchoconstriction, was observed. When L‐NNA was added to the perfusing medium of HLPs pre‐treated with NS 398 or with indomethacin (15 μM), the basal PAP values were enhanced. However, in the combined presence of COX and NOS inhibitors, only a slight increase in the hypertensive responses to the highest doses of PAF was observed, whereas the PAF mediated actions at bronchial and cardiac level were unaffected.
This study indicates that (i) the cardiopulmonary actions induced by PAF are specifically modulated by endogenous NO through the NOS pathway, and (ii) COX‐2 isoform is involved in the pulmonary hypertensive, but not bronchoconstrictor, effects of PAF. Furthermore, an interaction between PAF stimulated COX, particularly COX‐2, and NOS pathways appears to take a functional role at both bronchial and cardiovascular level.

British Journal of Pharmacology (2001) 134, 777–788; doi:10.1038/sj.bjp.0704311
Formation of functional α3β4α5 human neuronal nicotinic receptors in Xenopus oocytes: a reporter mutation approach
Authors: Groot‐Kormelink Paul J , Boorman James P , Sivilotti Lucia G 
Published: January 2005

The α5 subunit participates to the formation of native neuronal nicotinic receptors, particularly in autonomic ganglia. Like the related β3 subunit, α5 forms functional recombinant receptors if expressed together with a pair of typical α and β subunits, but its effect on the properties of the resulting αβα5 receptor depends on the α and β subunits chosen and on the expression system. We used a reporter mutation approach to test whether α5, like β3, is incorporated as a single copy in human α3β4α5 receptors expressed in oocytes.
As previously reported, the main indication of the presence of α5 in α3β4α5wt was an increase in apparent receptor desensitization (compared with α3β4 receptors). If the α3β4α5 receptor bore a 9′T mutation in the second transmembrane domain of either α3 or β4, α5 incorporation produced a decrease in ACh sensitivity (by 4 fold for α3LTβ4α5 vs α3LTβ4 and by 40 fold for α3β4LTα5 vs α3β4LT). The much greater effect observed in α3β4LTα5 receptors accords with the hypothesis that α5 takes the place of a β subunit in the receptor.
Introducing a 9′T mutation in α5 had no effect on the agonist sensitivity of α3β4α5 receptors, but reduced apparent desensitisation, as judged by the sag in the current response to high agonist concentrations.
Introducing the 9′T mutation in α3 or β4 in the triplet receptor reduced the EC50 for ACh by a similar extent (7 and 9 fold, respectively), suggesting that α3β4α5 receptors contain two copies each of α and β and therefore only one copy of α5.

British Journal of Pharmacology (2001) 134, 789–796; doi:10.1038/sj.bjp.0704313
Ketamine and its preservative, benzethonium chloride, both inhibit human recombinant α7 and α4β2 neuronal nicotinic acetylcholine receptors in Xenopus oocytes
Authors: Coates Kristen M , Flood Pamela 
Published: January 2005

Ketamine is a dissociative anaesthetic that is formulated as Ketalar, which contains the preservative benzethonium chloride (BCl). We have studied the effects of pure racemic ketamine, the preservative BCl and the Ketalar mixture on human neuronal nicotinic acetylcholine receptors (nAChRs) composed of the α7 subunit or α4 and β2 subunits expressed in Xenopus laevis oocytes.
Ketamine inhibited responses to 1 mM acetylcholine (ACh) in both the human α7 and α4β2 nAChRs, with IC50 values of 20 and 50 μM respectively. Inhibition of the α7 nAChRs occurred within a clinically relevant concentration range, while inhibition of the α4β2 nAChR was observed only at higher concentrations. The Ketalar formulation inhibited nAChR function more effectively than was expected given its ketamine concentration. The surprising increased inhibitory potency of Ketalar compared with pure ketamine appeared to be due to the activity of BCl, which inhibited both α7 (IC50 value of 122 nM) and α4β2 (IC50 value of 49 nM) nAChRs at concentrations present in the clinical formulation of Ketalar.
Ketamine is a noncompetitive inhibitor at both the α7 and α4β2 nAChR. In contrast, BCl causes a parallel shift in the ACh dose‐response curve at the α7 nAChR suggesting competitive inhibition. Ketamine causes both voltage‐dependent and use‐dependent inhibition, only in the α4β2 nAChR.
Since α7 nAChRs are likely to be inhibited during clinical use of Ketalar, the actions of ketamine and BCl on this receptor subtype may play a role in the profound analgesia, amnesia, immobility and/or autonomic modulation produced by this anaesthetic.

British Journal of Pharmacology (2001) 134, 871–879; doi:10.1038/sj.bjp.0704315
Mechanism of trypsin‐induced endothelium‐dependent vasorelaxation in the porcine coronary artery
Authors: Nakayama Tetsuzo , Hirano Katsuya , Nishimura Junji , Takahashi Shosuke , Kanaide Hideo 
Published: January 2005

To investigate the mechanism underlying the trypsin‐induced endothelium‐dependent relaxation, cytosolic Ca2+ concentration ([Ca2+]i) and tension development of smooth muscle were simultaneously monitored in the porcine coronary artery, and [Ca2+]i of in situ endothelial cells were monitored in the porcine aortic valvular strips, using fura‐2 fluorometry.
During the contraction induced by 30 nM U46619, a thromboxane A2 analogue, 100 nM trypsin induced a rapid transient significant decrease in both [Ca2+]i (from 67.9±5.1 to 15.7±4.4%) and tension (from 97.5±9.2 to 16.8±3.5%) of smooth muscle only in the presence of endothelium (100% level was assigned to the level obtained with the 118 mM K+‐induced contraction). [Ca2+]i and the tension thus returned to the levels prior to the application of trypsin by 5 and 10 min, respectively.
The initial phase of this relaxation was partly inhibited by 100 μM Nω‐nitro‐L‐arginine (L‐NOARG), and was completely inhibited by L‐NOARG plus 40 mM K+ or L‐NOARG plus 100 nM charybdotoxin and 100 nM apamin, while the late phase of the relaxation was inhibited by L‐NOARG alone.
Trypsin induced a transient [Ca2+]i elevation in the endothelial cells mainly due to the Ca2+ release from the intracellular stores, at the concentrations (1 – 100 nM) similar to those required to induce relaxation.
In conclusion, trypsin induced an elevation in [Ca2+]i mainly due to Ca2+ release in endothelial cells, and thereby caused endothelium‐dependent relaxation. The early phase of relaxation was due to nitric oxide and hyperpolarizing factors, while the late phase was mainly due to nitric oxide in the porcine coronary artery.

British Journal of Pharmacology (2001) 134, 815–826; doi:10.1038/sj.bjp.0704318
The effects of heparin on the adhesion of human peripheral blood mononuclear cells to human stimulated umbilical vein endothelial cells
Authors: Smailbegovic Amir , Lever Rebecca , Page Clive P 
Published: January 2005

The effects of unfractionated heparin (UH) and a selectively O‐desulphated derivative of heparin (ODSH), lacking anticoagulant activity, on the adhesion of human peripheral blood mononuclear cells (HPBMNC) to human stimulated umbilical vein endothelial cells (HUVECs), were investigated.
For comparison, the effects of poly‐L‐glutamic acid (PGA), a large polyanionic molecule without sulphate groups and two different molecular weight sulphated dextrans (DS 5 k and DS 10 k) were studied.
UH (50 – 1000 u ml−1) significantly (P<0.05) inhibited the adhesion of HPBMNC to HUVECs, stimulated with IL‐1β (100 u ml−1), TNF‐α (1000 u ml−1) or LPS (100 μg ml−1), when the drugs were added together with stimuli to HUVECs and coincubated for 6 h. Such effects on adhesion occurred with limited influence on expression of relevant endothelial adhesion molecules (ICAM‐1 and VCAM‐1).
UH (100 – 1000 u ml−1), when added to prestimulated HUVECs, significantly (P<0.05) increased adhesion of mononuclear cells to endothelium at the higher concentrations tested, without any effect on adhesion molecule expression. In contrast, the opposite effect was observed when human polymorphonuclear leucocyte adhesion was examined, under the same experimental conditions, suggesting that the observed potentiation of HPBMNC adhesion is cell specific.
The effects of UH on HPBMNC adhesion were shared by the non‐anticoagulant ODSH (600 – 6000 μg ml−1) but not by sulphated dextrans or PGA (300 – 6000 μg ml−1).
Heparin affects the adhesion of HPBMNC to stimulated endothelium, in both an inhibitory and potentiating manner, effects which are unrelated to its anticoagulant activity and not solely dependent on molecular charge characteristics.

British Journal of Pharmacology (2001) 134, 827–836; doi:10.1038/sj.bjp.0704321
Divergent effects of corticotropin releasing hormone on endothelial cell nitric oxide synthase are associated with different expression of CRH type 1 and 2 receptors
Authors: Cantarella Giuseppina , Lempereur Laurence , Lombardo Gabriella , Chiarenza Andrea , Pafumi Carlo , Zappalà Giovanna , Bernardini Renato 
Published: January 2005

Endothelium is a target for an array of factors involved in inflammation. Endothelial cells express receptors for CRH, a neuropeptide produced during inflammation. We report both the concentration‐dependent inhibitory effect of CRH upon cytokine‐stimulated nitrite release by H5V murine endothelioma cells, and its stimulatory one in HUVEC cells.
Western blot analysis showed that CRH inhibits cytokine‐stimulated iNOS protein in H5V cells, and, instead, potentiated it in HUVEC cells.
H5V cells expressed both CRH receptors (CRH‐R1 and R2) mRNAs, whereas HUVEC cells expressed the CRH‐R2 mRNA solely.
CRH increased medium nitrites and iNOS protein expression in H5V cells pretreated with the selective CRH‐R1 antagonist CP 154,526. However, the selective CRH‐R2 antagonist anti‐Svg‐30 failed to produce similar effects. In fact, anti‐Svg‐30 inhibited CRH‐induced increase of nitrite release and iNOS expression in HUVEC cells.
Our results confirm the activating role of CRH on endothelial cells, although it suggests its possible inhibitory role in the late phase of the inflammatory response. NO‐mediated effects of CRH on endothelial cells could be exploited in therapeutic strategies related to inflammatory and/or degenerative diseases.

British Journal of Pharmacology (2001) 134, 837–844; doi:10.1038/sj.bjp.0704322
Molecular targets for cannabidiol and its synthetic analogues: effect on vanilloid VR1 receptors and on the cellular uptake and enzymatic hydrolysis of anandamide
Authors: Bisogno Tiziana , Hanuš Lumír , De Petrocellis Luciano , Tchilibon Susanna , Ponde Datta E , Brandi Ines , Moriello Aniello Schiano , Davis John B , Mechoulam Raphael , Di Marzo Vincenzo 
Published: January 2005

(−)‐Cannabidiol (CBD) is a non‐psychotropic component of Cannabis with possible therapeutic use as an anti‐inflammatory drug. Little is known on the possible molecular targets of this compound. We investigated whether CBD and some of its derivatives interact with vanilloid receptor type 1 (VR1), the receptor for capsaicin, or with proteins that inactivate the endogenous cannabinoid, anandamide (AEA).
CBD and its enantiomer, (+)‐CBD, together with seven analogues, obtained by exchanging the C‐7 methyl group of CBD with a hydroxy‐methyl or a carboxyl function and/or the C‐5′ pentyl group with a di‐methyl‐heptyl (DMH) group, were tested on: (a) VR1‐mediated increase in cytosolic Ca2+ concentrations in cells over‐expressing human VR1; (b) [14C]‐AEA uptake by RBL‐2H3 cells, which is facilitated by a selective membrane transporter; and (c) [14C]‐AEA hydrolysis by rat brain membranes, which is catalysed by the fatty acid amide hydrolase.
Both CBD and (+)‐CBD, but not the other analogues, stimulated VR1 with EC50=3.2 – 3.5 μM, and with a maximal effect similar in efficacy to that of capsaicin, i.e. 67 – 70% of the effect obtained with ionomycin (4 μM). CBD (10 μM) desensitized VR1 to the action of capsaicin. The effects of maximal doses of the two compounds were not additive.
(+)‐5′‐DMH‐CBD and (+)‐7‐hydroxy‐5′‐DMH‐CBD inhibited [14C]‐AEA uptake (IC50=10.0 and 7.0 μM); the (−)‐enantiomers were slightly less active (IC50=14.0 and 12.5 μM). CBD and (+)‐CBD were also active (IC50=22.0 and 17.0 μM).
CBD (IC50=27.5 μM), (+)‐CBD (IC50=63.5 μM) and (−)‐7‐hydroxy‐CBD (IC50=34 μM), but not the other analogues (IC50>100 μM), weakly inhibited [14C]‐AEA hydrolysis.
Only the (+)‐isomers exhibited high affinity for CB1 and/or CB2 cannabinoid receptors.
These findings suggest that VR1 receptors, or increased levels of endogenous AEA, might mediate some of the pharmacological effects of CBD and its analogues. In view of the facile high yield synthesis, and the weak affinity for CB1 and CB2 receptors, (−)‐5′‐DMH‐CBD represents a valuable candidate for further investigation as inhibitor of AEA uptake and a possible new therapeutic agent.

British Journal of Pharmacology (2001) 134, 845–852; doi:10.1038/sj.bjp.0704327
Antagonism of AT2 receptors augments Angiotensin II‐induced abdominal aortic aneurysms and atherosclerosis
Authors: Daugherty Alan , Manning Michael W , Cassis Lisa A 
Published: January 2005

We have recently demonstrated that chronic infusion of Angiotensin II into apoE−/− mice promotes the development of abdominal aortic aneurysms. To determine the involvement of specific Angiotensin II receptors in this response, we co‐infused Angiotensin II (1000 ng kg−1 min−1 for 28 days) with losartan (30 mg kg−1 day−1) or PD123319 (3 mg kg−1 day−1) to antagonize AT1 and AT2 receptors, respectively.
Infusion of Angiotensin II promoted the development of abdominal aortic aneurysms in 70% of mature female apoE−/− mice. The formation of aortic aneurysms was totally inhibited by co‐infusion of Angiotensin II with losartan (30 mg kg−1 day−1; P=0.003). In contrast, the co‐infusion of Angiotensin II with PD123319 resulted in a marked increase in the incidence and severity of aortic aneurysms.
To determine whether AT2 antagonism also promoted Angiotensin II‐induced atherosclerosis, Angiotensin II was infused into young female apoE−/− mice that had little spontaneous atherosclerosis. In these mice, co‐infusion of PD123319 led to a dramatic increase in the extent of atherosclerosis. This increase was associated with no change in plasma lipid concentrations and only transient and modest increases in blood pressure during co‐infusion with PD123319.
While antagonism of AT1 receptors totally prevented the formation of aneurysms, antagonism of AT2 receptors promoted a large increase in the severity of Angiotensin II‐induced vascular pathology.

British Journal of Pharmacology (2001) 134, 865–870; doi:10.1038/sj.bjp.0704331
Effects of inhibition of PDE4 and TNF‐α on local and remote injuries following ischaemia and reperfusion injury
Authors: Souza Danielle G , Cassali Geovanni D , Poole Steve , Teixeira Mauro M 
Published: January 2005

The effects of phosphodiesterase (PDE)4 and TNF‐α inhibition were assessed on the local and remote injuries following intestinal ischaemia and reperfusion (I/R) injury in rats.
The PDE4 inhibitor rolipram dose‐dependently (1 – 10 mg kg−1) suppressed the local (intestine) and remote (lung) increases in vascular permeability and neutrophil recruitment following mild I/R injury. SB207499 (ariflo), a structurally‐distinct PDE4 inhibitor, also suppressed the injuries following mild I/R injury.
In a severe model of I/R injury, treatment with rolipram (10 mg kg−1) partially reversed the local and remote increases in vascular permeability, neutrophil recruitment, intestinal haemorrhage and intestinal LTB4 concentrations. The anti‐TNF‐α anti‐serum was more effective than rolipram at inhibiting local and remote injuries and prevented the lethality associated with severe I/R.
Rolipram and anti‐TNF‐α prevented the increase in the concentrations of TNF‐α in the lung and intestine, but rolipram only partially inhibited the elevation of this cytokine in serum. Rolipram had little effect on the increases of IL‐1ß concentrations in lung and serum, whereas treatment with anti‐TNF‐α markedly increased the concentration of this cytokine. Concentrations of IL‐10 rose significantly in the lung and serum and these increases were blocked by rolipram or anti‐TNF‐α.
The capacity of PDE4 inhibitors to block the recruitment of neutrophils into tissues, the production of LTB4 and of the pro‐inflammatory cytokines TNF‐α, IL‐1ß and IL‐6 appear to underlie their anti‐inflammatory effects in our model of I/R injury. Overall, PDE4 inhibition was less effective than inhibition of TNF‐α for protection against I/R injury.

British Journal of Pharmacology (2001) 134, 985–994; doi:10.1038/sj.bjp.0704336
A novel transcription factor inhibitor, SP100030, inhibits cytokine gene expression, but not airway eosinophilia or hyperresponsiveness in sensitized and allergen‐exposed rat
Authors: Huang Tung‐Jung , Adcock Ian M , Chung K Fan 
Published: January 2005

We examined the effect of SP100030, a novel inhibitor of activator protein‐1 (AP‐1) and nuclear factor (NF)‐κB transcription factors, in a rat model of asthma.
Sensitized Brown‐Norway rats were treated with SP100030 (20 mg kg−1 day−1 for 3 days) intraperitoneally prior to allergen challenge. Allergen exposure of sensitized rats induced bronchial hyperresponsiveness (BHR), accumulation of inflammatory cells in bronchoalveolar lavage (BAL) fluid, and also an increase in eosinophils and CD2+, CD4+ and CD8+ T‐cells in the airways together with mRNA expression for IL‐2, IL‐4, IL‐5, IL‐10, and IFN‐γ.
Pre‐treatment with SP100030 inhibited BAL lymphocyte influx (P<0.03), specifically reduced CD8+ T‐cell infiltration in the airway submucosa (P<0.03), and mRNA expression for IL‐2, IL‐5, and IL‐10 (P<0.05). Neutrophil, eosinophil, and CD4+ T‐cells accumulation in the airways and BHR were not affected by SP100030.
Our results indicate that suppression of IL‐2 and IL‐5 mRNA expression may not necessarily lead to suppression of BHR. The expression of IL‐5 mRNA may contribute to the airway accumulation of eosinophils, but does not correlate with the extent of eosinophilia.
The joint AP‐1 and NF‐κB inhibitor, SP100030, selectively inhibits CD8+ T‐cells, and mRNA expression of both Th1 and Th2 cytokines in vivo, but does not inhibit allergen‐induced airway eosinophilia and BHR.

British Journal of Pharmacology (2001) 134, 1029–1036; doi:10.1038/sj.bjp.0704344
Pharmacological characteristics of solid‐phase von Willebrand factor in human platelets
Authors: Radomski Anna , Stewart Michael W , Jurasz Paul , Radomski Marek W 
Published: January 2005

The pharmacological characteristics of solid‐phase von Willebrand factor (svWF), a novel platelet agonist, were studied.
Washed platelet suspensions were obtained from human blood and the effects of svWF on platelets were measured using aggregometry, phase‐contrast microscopy, flow cytometry and zymography.
Incubation of platelets with svWF (0.2 – 1.2 μg ml−1) resulted in their adhesion to the ligand, while co‐incubations of svWF with subthreshold concentrations of ADP, collagen and thrombin resulted in aggregation.
6B4 inhibitory anti‐glycoprotein (GP)Ib antibodies abolished platelet adhesion stimulated by svWF, while aggregation was reduced in the presence of 6B4 and N‐Acetyl‐Pen‐Arg‐Gly‐Asp‐Cys, an antagonist of GPIIb/IIIa.
Platelet adhesion stimulated with svWF was associated with a concentration‐dependent increase in expression of GPIb, but not of GPIIb/IIIa.
In contrast, collagen (0.5 – 10.0 μg ml−1) caused down‐regulation of GPIb and up‐regulation of GPIIb/IIIa in platelets.
Solid‐phase vWF (1.2 μg ml−1) resulted in the release of MMP‐2 from platelets.
Inhibition of MMP‐2 with phenanthroline (10 μM), but not with aspirin or apyrase, inhibited platelet adhesion stimulated with svWF.
In contrast, human recombinant MMP‐2 potentiated both the effects of svWF on adhesion and up‐regulation of GPIb.
Platelet adhesion and aggregation stimulated with svWF were reduced by S‐nitroso‐n‐acetyl‐penicillamine, an NO donor, and prostacyclin.
Thus, stimulation of human platelets with svWF leads to adhesion and aggregation that are mediated via activation of GPIb and GPIIb/IIIa, respectively.
Mechanisms of activation of GPIb by svWF involve the release of MMP‐2, and are regulated by NO and prostacyclin.

British Journal of Pharmacology (2001) 134, 1013–1020; doi:10.1038/sj.bjp.0704345
Nucleoside transporter subtype expression: effects on potency of adenosine kinase inhibitors
Authors: Sinclair C J D , Powell A E , Xiong W , LaRivière C G , Baldwin S A , Cass C E , Young J D , Parkinson F E 
Published: January 2005

Adenosine kinase (AK) inhibitors can enhance adenosine levels and potentiate adenosine receptor activation. As the AK inhibitors 5′ iodotubercidin (ITU) and 5‐amino‐5′‐deoxyadenosine (NH2dAdo) are nucleoside analogues, we hypothesized that nucleoside transporter subtype expression can affect the potency of these inhibitors in intact cells.
Three nucleoside transporter subtypes that mediate adenosine permeation of rat cells have been characterized and cloned: equilibrative transporters rENT1 and rENT2 and concentrative transporter rCNT2. We stably transfected rat C6 glioma cells, which express rENT2 nucleoside transporters, with rENT1 (rENT1‐C6 cells) or rCNT2 (rCNT2‐C6 cells) nucleoside transporters.
We tested the effects of ITU and NH2dAdo on [3H]‐adenosine uptake and conversion to [3H]‐adenine nucleotides in the three cell types. NH2dAdo did not show any cell type selectivity. In contrast, ITU showed significant inhibition of [3H]‐adenosine uptake and [3H]‐adenine nucleotide formation at concentrations 100 nM in rENT1‐C6 cells, while concentrations 3 μM were required for C6 or rCNT2‐C6 cells.
Nitrobenzylthioinosine (NBMPR; 100 nM), a selective inhibitor of rENT1, abolished the effects of nanomolar concentrations of ITU in rENT1‐C6 cells.
This study demonstrates that the effects of ITU, but not NH2dAdo, in whole cell assays are dependent upon nucleoside transporter subtype expression. Thus, cellular and tissue differences in expression of nucleoside transporter subtypes may affect the pharmacological actions of some AK inhibitors.

British Journal of Pharmacology (2001) 134, 1037–1044; doi:10.1038/sj.bjp.0704349