bluuebunny/crossref_metadata_2025_split huggingface dataset:
Cytokines, nerve growth factor and inflammatory hyperalgesia: the contribution of tumour necrosis factor α
Authors: Woolf C. J. , Allchorne A. , Safieh‐Garabedian B. , Poole S. 
Published: July 2006

Peripheral inflammation is characterized by heightened pain sensitivity. This hyperalgesia is the consequence of the release of inflammatory mediators, cytokines and growth factors. A key participant is the induction of the neurotrophin nerve growth factor (NGF) by interleukin‐1β (IL‐1β).
Tumour necrosis factor α (TNFα) has been shown both to produce hyperalgesia and to upregulate IL‐1β. We have now examined whether the induction of TNFα in inflammatory lesions contributes to inflammatory sensory hypersensitivity by inducing IL‐1β and NGF.
The intraplantar injection of complete Freund's adjuvant (CFA) in adult rats produced a localized inflammation of the hindpaw with a rapid (3 h) reduction in withdrawal time in the hot plate test and in the mechanical threshold for eliciting the flexion withdrawal reflex.
The CFA‐induced inflammation resulted in significant elevation in the levels of TNFα, IL‐1β and NGF in the inflamed paw. In the case of TNFα, an elevation was detected at 3 h, rose substantially at 6 h, peaked at 24 h and remained elevated at 5 days, with similar but smaller changes in the contralateral non‐inflamed hindpaw. No increase in serum TNFα was detected at 24 h post CFA injection.
Intraplantar recombinant murine TNFα injections produce a short‐lived (3–6 h) dose‐dependent (50–500 ng) increase in thermal and mechanical sensitivity which was significantly attenuated by prior administration of anti‐NGF antiserum.
Intraplantar TNFα (100–500 ng) also elevated at 6 but not 48 h the levels of IL‐1β and NGF in the hindpaw.
A single injection of anti‐TNFα antiserum, 1 h before the CFA, at a dose sufficient to reduce the effects of a 100 ng intraplantar injection of TNFα, significantly delayed the onset of the resultant inflammatory hyperalgesia and reduced IL‐1β but not NGF levels measured at 24 h.
The elevation of TNFα in inflammation, by virtue of its capacity to induce IL‐1β and NGF, may contribute to the initiation of inflammatory hyperalgesia.
Cardiovascular effects of a low‐dose combination of ramipril and felodipine in spontaneously hypertensive rats
Authors: Mervaala Eero M. A. , Teräväinen Terttu‐Liisa , Malmberg Lena , Laakso Juha , Vapaatalo Heikki , Karppanen Heikki 
Published: July 2006

Cardiovascular effects of submaximal antihypertensive doses of the angiotensin converting enzyme inhibitor, ramipril (0.25 mg kg−1 day−1 in the food), and the calcium channel blocker, felodipine (0.4 mg kg−1 day−1 subcutaneously by osmotic minipump), both alone and in combination, were examined in spontaneously hypertensive rats (SHR) in a four‐week study.
Both ramipril and felodipine as monotherapy decreased systolic blood pressure. The antihypertensive effect of the drug combination was more than that of ramipril treatment alone, but not significantly better than that of felodipine monotherapy. Ramipril or felodipine treatments did not significantly affect the heart rate, either alone or in combination.
The beneficial effect of ramipril monotherapy on left ventricular hypertrophy was more prominent than that of felodipine. The cardioprotective effect of felodipine was improved when combined to ramipril. The systolic blood pressure at the end of the experimental period correlated only weakly with left ventricular hypertrophy.
Responses of mesenteric arterial rings in vitro were examined at the end of the four‐week study. Ramipril and felodipine monotherapies as well as their combination markedly improved the endothelium‐dependent vascular relaxation responses to acetylcholine. The combination of ramipril and felodipine slightly enhanced the endothelium‐independent vascular relaxation responses to sodium nitroprusside. Ramipril treatment alone slightly diminished the vascular contractile responses to noradrenaline. Neither ramipril nor felodipine alone or in combination affected the vascular contractile responses to potassium chloride.
Ramipril treatment, both alone and in combination with felodipine, caused a three fold increase in plasma renin activity. Serum aldosterone, fasting blood glucose level, serum insulin and the 24 hour urinary excretions of sodium, potassium, magnesium, calcium, phosphorus or protein were not significantly affected by the drug treatments.
Our findings suggest that a better overall control of hypertension and end‐organ damages, without an increase in adverse effects, can be achieved by the combination of submaximal antihypertensive doses of felodipine and ramipril than by monotherapy with either drug alone.
Inhibitory responses to exogenous adenosine in murine proximal and distal colon
Authors: Zizzo Maria Grazia , Mulè Flavia , Serio Rosa 
Published: July 2006

The aims of the present study were firstly, to characterize pharmacologically the subtypes of P1purinoreceptors involved in the inhibitory effects induced by exogenous adenosine in longitudinal smooth muscle of mouse colon, and secondly, to examine differences in the function and distribution of these receptors between proximal and distal colon.Adenosine (100 μM–3 mM) caused a concentration‐dependent reduction of the amplitude of spontaneous contractions in the proximal colon, and muscular relaxation in the distal colon. In the proximal colon, adenosine effects were antagonized by a selective A1receptor antagonist, 1,3‐dipropyl‐8‐cyclopentylxanthine (DPCPX, 10 nM), but were not modified by 3,7‐dimethyl‐1‐propargylxanthine (DMPX, 10 μM) or by 9‐chloro‐2‐(2‐furanyl)‐5‐((phenylacetyl)amino)‐ [1,2,4]triazolo[1,5‐c]quinazoline (MRS 1220, 0.1 μM), selective A2and A3receptor antagonists, respectively. In the distal colon, adenosine effects were antagonized by DPCPX, DMPX, and by a selective A2Breceptor antagonist, 8‐[4‐[((4‐cyanophenyl)carbamoylmethyl)oxy]phenyl]‐1,3‐di(n‐propyl) xanthine (MRS 1754, 10 μM), but not by 8‐(3‐chlorostyryl)‐caffeine (CSC, 10 μM), a selective A2Areceptor antagonist, or by MRS 1220.Tetrodotoxin (TTX 1 μM), the nitric oxide (NO) synthase inhibitor,N‐nitro‐L‐arginine methyl ester (L‐NAME, 100 μM), or 1H‐[1,2,4]oxadiazolo[4,3‐a]quinoxalin‐1‐one (10 μM), an inhibitor of soluble guanylyl cyclase, reduced adenosine effects only in distal colon. In addition,L‐NAME induced a further reduction of adenosine relaxation in the presence of DPCPX, but not in the presence of MRS 1754.From these results we conclude that, in the murine proximal colon, adenosine induces inhibitory effectsviaTTX‐insensitive activation of A1receptor. In the distal colon, adenosine activates both A1and A2Breceptors, the latter located on enteric inhibitory neurons releasing NO.British Journal of Pharmacology(2006)148, 956–963. doi:10.1038/sj.bjp.0706808
Protective effects of relaxin in ischemia/reperfusion‐induced intestinal injury due to splanchnic artery occlusion
Authors: Masini Emanuela , Cuzzocrea Salvatore , Mazzon Emanuela , Muià Carmelo , Vannacci Alfredo , Fabrizi Francesca , Bani Daniele 
Published: July 2006

Splanchnic artery occlusion (SAO) followed by reperfusion causes endothelial injury and inflammation which contribute to the pathophysiology of shock. We investigated the effects of relaxin (RLX), known to afford protection against the deleterious effects of cardiac ischemia/reperfusion, given to rats subjected to splanchnic artery occlusion and reperfusion (SAO/R)‐induced splanchnic injury.
RLX (30 ng kg−1, 15 min. before reperfusion) significantly reduced the drop of blood pressure and high mortality rate caused by SAO/R. RLX also reduced histopathological changes, leukocyte infiltration (myeloperoxidase) and expression of endothelial cell adhesion molecules in the ileum. RLX counteracted free radical‐mediated tissue injury, as judged by significant decrease in the tissue levels of peroxidation and nitration products (malondialdehyde, nitrotyrosine), DNA damage markers (8‐hydroxy‐2′‐deoxyguanosine, poly‐ADP‐ribosylated DNA) and consumption of tissue antioxidant enzymes (superoxide dismutase). As a result, RLX led to a reduction of ileal cell apoptosis (caspase 3, terminal deoxynucleotidyltransferase‐mediated UTP end labeling). The effects of RLX appear specific, as inactivated RLX substituted for the bioactive hormone had no effects.
In conclusion, these results show that RLX exerts a clear‐cut protective effect in SAO/R‐induced splanchnic injury, likely due to endothelial protection, decreased leukocyte recruitment and hindrance of free radical‐mediated tissue injury leading to cell death, lethal complications and high mortality rate. Thus, RLX could be used therapeutically in intestinal ischemia.

British Journal of Pharmacology (2006) 148, 1124–1132. doi:10.1038/sj.bjp.0706811
Quantifying the association and dissociation rates of unlabelled antagonists at the muscarinic M3receptor
Authors: Dowling Mark R , Charlton Steven J 
Published: July 2006

Slow receptor dissociation kinetics has been implicated in the long clinical duration of action of the muscarinic receptor antagonist tiotropium. However, despite the potential benefits of new drugs with slow dissociation kinetics, the rate parameters of new compounds are seldom measured due to technical difficulties and financial implications associated with radiolabeling multiple ligands. Here we describe the development and optimisation of a medium throughput assay which is capable of measuring the kinetic parameters of novel, unlabelled compounds.Radioligand binding studies were performed with membranes derived from CHO cells recombinantly expressing the human M3muscarinic receptor.Initial characterisation of the radioligand [3H]‐NMS yielded on and off rates of 4.1±0.2 × 108 M−1 min−1and 0.015±0.0005 min−1, respectively.The specific binding of [3H]‐NMS was measured over time in the presence and absence of several concentrations of unlabelled competitor compounds. These data were analysed using a competition kinetic model to provide on and off rates for the unlabelled competitor. Comparison of the kinetically derived Kd (koff/kon) withKivalues generated at equilibrium showed an excellent correlation (r2=0.99), providing good validation of the method.The on and off rates were also used in theoretical computer simulations to successfully predict the effect of incubation time on apparent IC50values.This study demonstrates that a medium‐throughput competition kinetic binding assay can be used to determine accurate on and off rates of unlabelled compounds, providing the opportunity to optimise for kinetic parameters early in the drug discovery process.British Journal of Pharmacology(2006)148, 927–937. doi:10.1038/sj.bjp.0706819
Lipid lowering effects of Momordica charantia (Bitter Melon) in HIV‐1‐protease inhibitor‐treated human hepatoma cells, HepG2
Authors: Nerurkar Pratibha V , Lee Yun Kyung , Linden Ellen H , Lim Steven , Pearson Laurel , Frank Jennifer , Nerurkar Vivek R 
Published: July 2006

Hyperlipidemic effects of HIV‐1‐protease inhibitors (PI) are associated with increased hepatic production of triglyceride (TG)‐rich lipoproteins, rather than lipoprotein clearance. PI are known to increase apolipoprotein B (apoB) secretion, apoC‐III mRNA expression and decrease apoA‐1 secretion. Nutritional therapy remains an important strategy to manage PI‐associated hyperlipidemia.
This study investigated the in vitro efficacy of Asian vegetable, Momordica charantia or bitter melon (BM) to ameliorate PI‐associated apoB and lipid abnormalities in HepG2 cells.
Our study demonstrates that bitter melon juice (BMJ) significantly reduced apoB secretion and apoC‐III mRNA expression and normalized apoA‐I expression in PI‐treated HepG2 cells. BMJ also significantly reduced cellular TG and microsomal TG transfer protein, suggesting that lipid bioavailability and lipidation of apoB assembly may play a role in decreased apoB secretion.
Identifying molecular targets of BM may offer alternative dietary strategies to decrease PI‐associated hyperlipidemia and improve quality of life among HIV‐1‐infected patients.

British Journal of Pharmacology (2006) 148, 1156–1164. doi:10.1038/sj.bjp.0706821
Investigation on the relationship between cannabinoid CB1and opioid receptors in gastrointestinal motility in mice
Authors: Carai Mauro A M , Colombo Giancarlo , Gessa Gian Luigi , Yalamanchili Ratnakumar , Basavarajppa Balapal S , Hungund Basalingappa L 
Published: July 2006

This study investigated whether (a) cannabinoid CB1receptor knockout (CB1−/−) mice displayed altered gastrointestinal transit and (b) cannabinoid CB1and opioid receptors functionally interact in the regulation of gastrointestinal transit.Gastrointestinal transit was assessed by the Whole Gastrointestinal Transit, measuring the excretion time of an intragastrically administered marker (whole intestine), and the Upper Gastrointestinal Transit, measuring the distance covered by the marker in the small intestine.CB1−/−and homozygous CB1+/+(CB1+/+) mice did not differ in both whole gut and small intestine transit. CB1−/−and CB1+/+mice were equally responsive to the inhibitory effect of morphine (10 mg kg−1) and loperamide (3 mg kg−1) on whole gut transit.Additionally, in CD1 mice the cannabinoid CB1receptor antagonist, rimonabant (0–0.5 mg kg−1), failed to block the inhibitory effect of morphine (0–1.25 mg kg−1) and loperamide (0–0.5 mg kg−1) on transit in small and whole intestine. Similarly, the opioid receptor antagonists, naloxone (0–1 mg kg−1) and naltrexone (0–10 mg kg−1), failed to block the inhibitory effect of the cannabinoid WIN 55,212‐2 (0–3 mg kg−1) on transit in small and whole intestine.These results suggest that (a) compensatory mechanisms likely developed in CB1−/−mice to overcome the lack of inhibitory function of endocannabinoid system; (b) cannabinoid and opioid receptor systems did not interact in regulating gastrointestinal transit in mice.British Journal of Pharmacology(2006)148, 1043–1050. doi:10.1038/sj.bjp.0706824
Neuropeptide B and W: neurotransmitters in an emerging G‐protein‐coupled receptor system
Authors: Singh Gurminder , Davenport Anthony P 
Published: July 2006

Deorphanised G‐protein‐coupled receptors represent new and expanding targets for drug development. Neuropeptide B (NPB) and W (NPW) have recently been identified as the cognate endogenous ligands for the orphan receptor GPR7, now designated as NPBW1. NPB and NPW also bound to a second related orphan receptor, GPR8, now designated as NPBW2 that is present in humans but not rats or mice. In humans, high levels of NPW mRNA have been visualised in the substantia nigra, whereas moderate expression levels have been detected in the amygdala and hippocampus. In peripheral tissues, expression of NPW mRNA has been confirmed in the progenital system, comprising the kidney, testis, uterus, ovary and placenta, and also in stomach homogenates. Immunocytochemical, molecular biological and autoradiography techniques have revealed a discrete CNS distribution for NPBW1 in human, mouse and rat. Highest expression of NPBW1 mRNA and protein was identified in the amygdala and hypothalamic nuclei known to regulate feeding behaviour. [125I]‐NPW bound with a single high affinity to rat amygdala, KD=0.44 nM and 150 fmol mg−1 protein. Physiological studies demonstrate that intracerebroventricular infusion of NPBW1 ligands modulates feeding behaviour, regulates the release of corticosterone, prolactin and growth hormone while also manipulating pain pathway. Mouse knockout models of the gene encoding either NPB or NPBW1 have a gender‐specific phenotype, with moderate obesity evident in males but not females. Further investigation is required to elucidate the precise physiological role of NPB and NPW as neurotransmitters.British Journal of Pharmacology (2006) 148, 1033–1041. doi:10.1038/sj.bjp.0706825
Vitamin A active metabolite, all‐trans retinoic acid, induces spinal cord sensitization. I. Effects after oral administration
Authors: Romero‐Sandoval E A , Molina C , Alique M , Moreno‐Manzano V , Lucio F J , Herrero J F 
Published: July 2006

Background and purpose:Retinoic acid is an active metabolite of vitamin A involved in the modulation of the inflammatory and nociceptive responses. The aim of the present study was to analyze the properties of spinal cord neuronal responses of male Wistar rats treated with all‐trans retinoic acid (ATRA) p.o. in the normal situation and under carrageenan‐induced inflammation. We also studied the expression and distribution of cyclooxygenases (COX) in the spinal cord.Experimental approach:Properties of spinal cord neurons were studied by means of the single motor unit technique. The expression of COX enzymes in the spinal cord was assessed by Western blot analysis and immunohistochemistry.Key results:Intensity thresholds for mechanical and electrical stimulation (C‐fibers) were significantly lower in animals treated with ATRA than vehicle, either in normal rats or in rats with inflammation. The size of cutaneous receptive fields was also larger in animals treated with ATRA in the normal and inflammatory conditions. The expression of COX‐2 enzyme, but not COX‐1, was significantly higher in animals treated with ATRA. COX‐2 labeling was observed in dorsal horn cells and in ventral horn motoneurons.Conclusions and implications:In conclusion, the oral treatment with ATRA in rats induces a sensitization‐like effect on spinal cord neuronal responses similar to that observed in animals with inflammation and might explain the enhancement of allodynia and hyperalgesia observed in previously published behavioral experiments. The mechanism of action involves an over‐expression of COX‐2, but not COX‐1, in dorsal and ventral horn areas of the lumbar spinal cord.British Journal of Pharmacology (2006) 149, 56–64. doi:10.1038/sj.bjp.0706829
In-frame deletion in the EGF receptor alters kinase inhibition by gefitinib
Authors: Sakai Kazuko , Yokote Hideyuki , Murakami-Murofushi Kimiko , Tamura Tomohide , Saijo Nagahiro , Nishio Kazuto 
Published: July 2006

The existence of an in-frame deletion mutant correlates with the sensitivity of lung cancers to EGFR (epidermal growth factor receptor)-targeted tyrosine kinase inhibitors. We reported previously that the in-frame 15-bp deletional mutation (delE746–A750 type deletion) was constitutively active in cells. Kinetic parameters are important for characterizing an enzyme; however, it remains unclear whether the kinetic parameters of deletion mutant EGFR are similar to those of wild-type EGFR. We analysed autophosphorylation in response to ATP and inhibition of gefitinib for deletion mutant EGFR and wild-type EGFR. Kinetic studies, examining autophosphorylation, were carried out using EGFR fractions extracted from 293-pΔ15 and 293-pEGFR cells transfected with deletion mutant EGFR and wild-type EGFR respectively. We demonstrated the difference in activities between unstimulated wild-type (Km for ATP=4.0±0.3 μM) and mutant EGFR (Km for ATP=2.5±0.2 μM). There was no difference in Km values between EGF-stimulated wild-type EGFR (Km for ATP=1.9±0.1 μM) and deletion mutant EGFR (Km for ATP=2.2±0.2 μM). These results suggest that mutant EGFR is active without ligand stimulation. The Ki value for gefitinib of the deletion mutant EGFR was much lower than that of wild-type EGFR. These results suggest that the deletion mutant EGFR has a higher affinity for gefitinib than wild-type EGFR.
Structure–function relationships for Schizophyllum commune trehalose phosphorylase and their implications for the catalytic mechanism of family GT-4 glycosyltransferases
Authors: Goedl Christiane , Griessler Richard , Schwarz Alexandra , Nidetzky Bernd 
Published: July 2006

The cDNA encoding trehalose phosphorylase, a family GT-4 glycosyltransferase from the fungus Schizophyllum commune, was isolated and expressed in Escherichia coli to yield functional recombinant protein in its full length of 737 amino acids. Unlike the natural phosphorylase that was previously obtained as a truncated 61 kDa monomer containing one tightly bound Mg2+, the intact enzyme produced in E. coli is a dimer and not associated with metal ions [Eis, Watkins, Prohaska and Nidetzky (2001) Biochem. J. 356, 757–767]. MS analysis of the slow spontaneous conversion of the full-length enzyme into a 61 kDa fragment that is fully active revealed that critical elements of catalysis and specificity of trehalose phosphorylase reside entirely in the C-terminal protein part. Intact and truncated phosphorylases thus show identical inhibition constants for the transition state analogue orthovanadate and α,α-trehalose (Ki≈1 μM). Structure-based sequence comparison with retaining glycosyltransferases of fold family GT-B reveals a putative active centre of trehalose phosphorylase, and results of site-directed mutagenesis confirm the predicted crucial role of Asp379, His403, Arg507 and Lys512 in catalysis and also delineate a function of these residues in determining the large preference of the wild-type enzyme for the phosphorolysis compared with hydrolysis of α,α-trehalose. The pseudo-disaccharide validoxylamine A was identified as a strong inhibitor of trehalose phosphorylase (Ki=1.7±0.2 μM) that displays 350-fold tighter binding to the enzyme–phosphate complex than the non-phosphorolysable substrate analogue α,α-thio-trehalose. Structural and electronic features of the inhibitor that may be responsible for high-affinity binding and their complementarity to an anticipated glucosyl oxocarbenium ion-like transition state are discussed.
Early alterations in myocardia and vessels of the diabetic rat heart: an FTIR microspectroscopic study
Authors: Toyran Neslihan , Lasch Peter , Naumann Dieter , Turan Belma , Severcan Feride 
Published: July 2006

Diabetes mellitus is associated with a high incidence and poor prognosis of cardiovascular disease. The aim of the present study was to examine the effect of relatively short-term (5 weeks) Type I diabetes on the left ventricle, the right ventricle and the vessel (vein) on the left ventricle of the myocardium at molecular level by FTIR (Fourier-transform infrared) microspectroscopy. The rats were categorized into two groups: control group (for the left ventricle myocardium, n=8; for the right ventricle myocardium, n=9; for the vein, n=9) and streptozotocin-induced diabetic group (for the left ventricle myocardium, n=7; for the right ventricle myocardium, n=9; for the vein, n=8). Two adjacent cross-sections of 9 μm thickness were taken from the ventricles of the hearts in two groups of rats by using a cryotome. The first sections were used for FTIR microspectroscopy measurements. The second serial sections were stained by haematoxylin/eosin for comparative purposes. Diabetes caused an increase in the content of lipids, an alteration in protein profile with a decrease in α-helix and an increase in β-sheet structure as well as an increase in glycogen and glycolipid contents in both ventricles and the vein. Additionally, the collagen content was found to be increased in the vein of the diabetic group. The present study demonstrated that diabetes-induced alterations in the rat heart can be detected by correlating the IR spectral changes with biochemical profiles in detail. The present study for the first time demonstrated the diabetes-induced alterations at molecular level in both ventricle myocardia and the veins in relatively short-term diabetes.