Endothelial cell (EC) and pericyte interactions are essential for the generation of stable microvascular networks in ischaemia, but these processes are disrupted in peripheral artery disease (PAD). We uncovered ECs are a major contributor of tumour necrosis factor-related apoptosis-inducing ligand (TRAIL) in the circulation that is compromised in PAD, and associates with reduced stable microvessels in ischaemic amputated tissues. Angiogenesis was assessed by Matrigel plug, wound healing, hind-limb ischaemia (HLI), aortic sprouting and in cells. EC-specific Trail-/- mice (TrailEC-/-) revealed ∼50-60% less EC/pericyte content in plugs and in wounds and reduced aortic microvascular sprouting in hypoxia. In vitro, TRAIL-deleted ECs formed fewer tubules, recruited less pericytes and prevented pericyte stabilisation. TrailEC-/- mice had impaired formation of stable microvessels in HLI, which associated with reduced blood perfusion to the limbs; findings also observed inTRAIL-receptor knockout (Trail-R-/-) mice. Remarkably, activating the TRAIL-R using MD5-1, an anti-mouse agonistic TRAIL-R mAb, in vivo restored blood perfusion and increased stable microvessels in ischaemic limbs and ex vivo stimulated aortic sprouts in TrailEC-/- mice. MD5-1 also stimulated angiogenesis in vitro. Single cell RNA-sequencing of ischaemic tissues identified multiple EC-pericyte interactions disrupted with TRAIL deletion in the endothelium. These studies identify EC-derived TRAIL as a new player in mediating angiogenesis and vessel stabilisation necessary for effective microvascular function. TRAIL-receptor agonists already used in clinical trials for cancer could be repurposed to stimulate stable and functional microvessel networks in PAD.

LINKED EDITORIALS:This Editorial is part of a series. To view the other Editorials in this series, visit: http://onlinelibrary.wiley.com/doi/10.1111/bph.12956/abstract; http://onlinelibrary.wiley.com/doi/10.1111/bph.12954/abstract; http://onlinelibrary.wiley.com/doi/10.1111/bph.12955/abstract and http://onlinelibrary.wiley.com/doi/10.1111/bph.12856/abstract. VIDEO:To view the video on the IUPHAR/BPS Guide to PHARMACOLOGY, visit: https://www.youtube.com/watch?v=Qhy3q33VtRI.

The Concise Guide to PHARMACOLOGY 2013/14 provides concise overviews of the key properties of over 2000 human drug targets with their pharmacology, plus links to an open access knowledgebase of drug targets and their ligands (www.guidetopharmacology.org), which provides more detailed views of target and ligand properties from the IUPHAR database. The full contents can be found at http://onlinelibrary.wiley.com/doi/10.1111/bph.12444/full. This compilation of the major pharmacological targets is divided into seven areas of focus: G protein-coupled receptors, ligand-gated ion channels, ion channels, catalytic receptors, nuclear hormone receptors, transporters and enzymes. These are presented with nomenclature guidance and summary information on the best available pharmacological tools, alongside key references and suggestions for further reading. A new landscape format has easy to use tables comparing related targets. It is a condensed version of material contemporary to late 2013, which is presented in greater detail and constantly updated on the website www.guidetopharmacology.org, superseding data presented in previous Guides to Receptors & Channels. It is produced in conjunction with NC-IUPHAR and provides the official IUPHAR classification and nomenclature for human drug targets, where appropriate. It consolidates information previously curated and displayed separately in IUPHAR-DB and GRAC and provides a permanent, citable, point-in-time record that will survive database updates.

The discovery of β-adrenoceptors in previously unsuspected cell types is contributing to the rethinking of new drug targets. Recent developments in β-adrenoceptor pharmacology might have excited and surprised James Black, given his interest in developing drugs based on the selective manipulation of receptors to alter physiological responses. β-adrenoceptors continue to generate surprises at molecular and pharmacological levels that often require knowledge of receptor location to interpret. In this review, we emphasize the use of fluorescent ligands as the most selective means of demonstrating receptor localization. Fluorescent ligand binding in live tissues can provide quantitative pharmacological data, under carefully controlled conditions, relevant to other signalling parameters. Consideration of the role of β-adrenoceptors in many cell types (previously ignored) is needed to understand the actions of drugs at β-adrenoceptors throughout the body, particularly in the lung epithelium, vascular endothelium, immune cells and other 'structural' and 'restorative' cell types.

In this issue of BJP we publish two letters commenting on the use of immunolabelling techniques. The first, from JC Ashton (Ashton, 2011) reinforces the need for strict criteria in assessing immunohistochemistry data as set out in a review by Atwood and Mackie (2010). The second, from SL Sandow and TH Grayson (Sandow and Grayson, 2011), is more concerned with Western Blots and comments on a paper by Weston et al. (2010). The latter paper was also the subject of an invited Commentary by Garland (2010). Both pieces of correspondence concern the need for inclusion of rigorous control data when reporting experiments employing immunotechniques. Similar factors apply whether the technique in question is histological or biochemical and, where possible, the use of both approaches can reinforce the finding made by one of them. The gist of the letter by Sandow and Grayson is that insufficient control data were included in a part of the study that reported Western Blots. After peer review of the letter and of the response by the authors, the scientific points raised were judged to be valid and, equally, the authors had most of the answers to hand. However, the fact that the answers were available does not mean that the points should not have been raised. It means that our system somehow failed to ensure that these details were available to the reader. Indeed, in responding to the comments, Edwards et al. (2011) point out that several other papers in the same issue could similarly be taken to task. Whether the submitting authors, the peer reviews or the journal's rules for submission or review are responsible for the omission of these details is not really relevant. The editorial procedures employed by BJP are as comprehensive as those employed by other leading life-science journals, although that is no reason to be complacent. By including the data requested by Sandow and Grayson, the Weston et al. paper has become more rigorous – why was it not there to begin with? It was only this ‘extra review layer’ of post-publication comment to the Editor that produced the more complete study. So we should take two lessons from this. First we should be pleased that the availability of the Letter to the Editor mechanism has stimulated scientific debate and helped obtain a satisfactory outcome. Perhaps we should be thinking about reinforcing the armamentarium available for readers' comments, given the technology developed for social media. Secondly, we should recognize that the application of immunological techniques to the detection and quantification of proteins in heterogeneous tissue carries many hazards that have been well highlighted elsewhere. One problem is that when antibodies are made available commercially there is often not as much data on quality control provided as should be expected, sometimes because it does not exist, although it should be emphasized that in the Weston et al. study the experiments were done, just not included in the original manuscript. Scientists employing these products are expected to ensure the quality of their own work although they might not be equipped to provide evidence for it themselves. Indeed, why should they when they have purchased a product in good faith from a recognized supplier? A recent useful series of articles in Naunyn Schmiedeberg's Archives of Pharmacology appear to highlight this problem for a large number of commercially available antibodies for GPCRs (Michel et al., 2009), pointing out that many of them could be shown to be non-selective when appropriate controls were carried out and making recommendations for minimum data required for publication of work using antibodies. Clearly, we need to specify more clearly what information and what controls are required when authors publish work based on antibodies, whether this be for Western Blots or immunocytochemistry. Fortunately, we do not have to re-invent the wheel. In addition to Michel et al. (2009), excellent editorials on this topic have been published in the Journal of Comparative Neurology (Saper and Sawchenko, 2003; Saper, 2005). We will be refining our instructions to authors in this regard.

This re-launch issue contains a themed section on 'QT Safety', dealing with drug-induced toxicities associated with prolongation of the cardiac QT interval (http://www3.interscience.wiley.com/journal/121548564/issueyear?year=2010). Subsequent issues will have themed sections on Imaging in Pharmacology (guest edited by Anthony Davenport and Craig Daly) and GPCRs (guest edited by Roger Summers; following on from the highly successful 2009 GPCR Issue (http://www3.interscience.wiley.com/journal/122575288/issue). Our new, fresh, blue cover design harmonises with our sister journal BJCP's similar green cover, symbolically indicating that our two journals, in the BPS stable, are now working together to cover all of pharmacology. The new design reflects the BPS logo (British Pharmacological Society). British Journal of Pharmacology (2010) 159, 1-4; doi:10.1111/j.1476-5381.2009.00635.x

Background and purpose: Pharmacological analysis of synergism or functional antagonism between different receptors commonly assumes that interacting receptors are located in the same cells. We have now investigated the distribution of α‐adrenoceptors, β‐adrenoceptors and cannabinoid‐like (GPR55) receptors in the mouse arteries. Experimental approach: Fluorescence intensity from vascular tissue incubated with fluorescent ligands (α 1 ‐adrenoceptor ligand, BODIPY‐FL‐prazosin, QAPB; β‐adrenoceptor ligand, TMR‐CGP12177; fluorescent angiotensin II; a novel diarylpyrazole cannabinoid ligand (Tocrifluor 1117, T1117) was measured with confocal microscopy. Small mesenteric and tail arteries of wild‐type and α 1B/D ‐adrenoceptor‐KO mice were used. Key results: T1117, a fluorescent form of the cannabinoid CB 1 receptor antagonist AM251, was a ligand for GPR55, with low affinity for CB 1 receptors. In mesenteric arterial smooth muscle cells, α 1A ‐adrenoceptors were predominantly located in different cells from those with β‐adrenoceptors, angiotensin receptors or cannabinoid‐like (GPR55) receptors. Cells with β‐adrenoceptors predominated at arterial branches. Endothelial cells expressed β‐adrenoceptors, α‐adrenoceptors and cannabinoid‐like receptors. Only endothelial α‐adrenoceptors appeared in clusters. Adventitia was a rich source of G protein‐coupled receptors (GPCRs), particularly fibroblasts and nerve tracts, where Schwann cells bound α‐adrenoceptor, β‐adrenoceptor and CB‐receptor ligands, with a mix of separate receptor locations and co‐localization. Conclusions and implications: Within each cell type, each GPCR had a distinctive heterogeneous distribution with limited co‐localization, providing a guide to the possibilities for functional synergism, and suggesting a new paradigm for synergism in which interactions may be either between cells or involve converging intracellular signalling processes. This article is part of a themed section on Imaging in Pharmacology. To view the editorial for this themed section visit http://dx.doi.org/10.1111/j.1476‐5381.2010.00685.x

British Journal of Pharmacology (BJP) is pleased to publish a new set of guidelines for reporting research involving animals, simultaneously with several other journals; the ‘ARRIVE’ guidelines (Animals in Research: Reporting In Vivo Experiments). This editorial summarizes the background to the guidelines, gives our view of their significance, considers aspects of specific relevance to pharmacology, re‐states BJP's guidelines for authors on animal experiments and indicates our commitment to carrying on discussion of this important topic. We also invite feedback via the British Pharmacological Society website.

Background and purpose:Theoretically, three alpha(1)-adrenoceptor subtypes can interact at the signalling level to alter vascular contraction or at the molecular level to alter each other's cellular location. The alpha(1A/B)-adrenoceptor knockout mouse (alpha(1A/B)-KO) was used to study the isolated alpha(1D)-adrenoceptor to consider these potential interactions in native tissue.Experimental approach:Pharmacological analysis of carotid and mesenteric arteries employed wire myography and fluorescent ligand binding (alpha(1)-adrenoceptor ligand BODIPY FL-prazosin, QAPB).Key results:alpha(1A/B)-KO carotid had clear alpha(1D)-adrenoceptor-induced contractions. In WT carotid alpha(1D)-adrenoceptor dominated but all three alpha(1)-subtypes participated. alpha(1A/B)-KO mesenteric had alpha(1D)-adrenoceptor responses with high sensitivity and small maximum, explaining how alpha(1D)-adrenoceptor could determine agonist sensitivity in WT. In both arteries alpha(1A/B)-KO fluorescence levels were reduced but pharmacologically more consistent with 'pure' alpha(1D)-adrenoceptors. alpha(1D)-Adrenoceptor binding in alpha(1A/B)-KO was observed on the cell surface and intracellularly and was present in a high proportion of smooth-muscle cells in both strains, regardless of artery type.Conclusions and implications:'Pure' alpha(1D)-adrenoceptor pharmacology in alpha(1A/B)-KO provides a quantitative standard. Functionally, the alpha(1D)- and alpha(1A)-adrenoceptors produce additive responses and do not significantly compensate for each other. alpha(1D)-Adrenoceptor contributes to sensitivity even in resistance arteries. In alpha(1A/B)-KO, the loss of alpha(1A)- and alpha(1B)-adrenoceptors is reflected by a general decrease in fluorescence, but similar binding distribution to WT indicates that the alpha(1D)-adrenoceptor location in native smooth-muscle cells is not influenced by other alpha(1)-adrenoceptors. Equivalent levels of receptors did not correspond to equivalent responses. In conclusion, alpha(1)-subtypes do not interact but provide independent alternative signals for vascular regulation.

In this issue, BJP is proud to publish an Endothelium Themed Section to celebrate the life of Robert F. Furchgott, who died on May 19th 2009. It is 30 years since he discovered endothelium-derived relaxant factor and a decade since he was awarded the Nobel Prize for this work. His discovery has led to an array of new therapeutic targets. The themed section includes three reviews on the pathophysiology of the endothelium and the drug targets that this presents, four research papers and three commentaries on research. This themed section also forms the nucleus of an online Virtual Issue that collects in one place further reviews and research papers on the topic of the 'Endothelium' that BJP and our sister journal BJCP have published in the past year, and that should help researchers and students to find the latest work in this field.

Background and purpose: Mesenteric and carotid arteries from the α1B/D‐adrenoceptor knockout (α1B/D‐KO) were employed to isolate α1A‐adrenoceptor pharmacology and location and to reveal these features in the wild‐type (WT) mouse.Experimental approach: Functional pharmacology by wire myography and receptor localization by confocal microscopy, using the fluorescent α1‐adrenoceptor ligand BODIPY FL‐Prazosin (QAPB), on mesenteric (an ‘α1A‐adrenoceptor’ tissue) and carotid (an ‘α1D‐adrenoceptor’ tissue) arteries.Key results: α1B/D‐KO mesenteric arteries showed straightforward α1A‐adrenoceptor agonist/antagonist pharmacology. WT had complex pharmacology with α1A‐ and α1D‐adrenoceptor components. α1B/D‐KO had a larger α1A‐adrenoceptor response suggesting compensatory up‐regulation: no increase in fluorescent ligand binding suggests up‐regulation of signalling. α1B/D‐KO carotid arteries had low efficacy α1A‐adrenoceptor responses. WT had complex pharmacology consistent with co‐activation of all three subtypes. Fluorescent binding had straightforward α1A‐adrenoceptor characteristics in both arteries of α1B/D‐KO. Fluorescent binding varied between cells in relative intracellular and surface distribution. Total fluorescence was reduced in the α1B/D‐KO due to fewer smooth muscle cells showing fluorescent binding. WT binding was greater and sensitive to α1A‐ and α1D‐adrenoceptor antagonists.Conclusions and implications: The straightforward pharmacology and fluorescent binding in the α1B/D‐KO was used to interpret the properties of the α1A‐adrenoceptor in the WT. Reduced total fluorescence in α1B/D‐KO arteries, despite a clear difference in the functionally dominant subtype, indicates that measurement of receptor protein is unlikely to correlate with function. Fewer cells bound QAPB in the α1B/D‐KO suggesting different cellular phenotypes of α1A‐adrenoceptor exist. The α1B/D‐KO provides robust assays for the α1A‐adrenoceptor and takes us closer to understanding multi‐receptor subtype interactions.

Theoretically, the three alpha-1-adrenoceptor (AR) subtypes can interact at signalling level to alter vascular contraction or at the molecular level to alter each other's cellular location. Double knockouts were used to study the isolated alpha-1A-AR and alpha-1D-AR and to consider their potential interactions in native tissue.

A themed section in this issue of Br J Pharmacol, on 'Advances in Nutritional Pharmacology', provides a valuable and timely update on progress in this area. The value of dietary components to improvement in health and, particularly, to prevention of cardiovascular disease and cancer, is frequently reported in the media and therefore often captures the attention of the wider public. Understanding the pharmacological mechanisms by which nutritional elements confer their health benefits enables us to keep the public informed, but also aids in the identification of new targets for drug development. In recent years there has been significant progress in this field. Four rapidly developing areas are reviewed. Vosper (2009) covers the identification of a receptor for niacin and the subsequent development of selective agonists as lipid lowering agents. Wu-Wong (2009) describes the development of new Vitamin D analogues for the treatment of cardiovascular disease. de Roos et al. (2009) provide detailed insight into how omega-3 fatty acids, also known as longchain n-3 polyunsaturated fatty acids (PUFAs) protect against cardiovascular disease. Zhou et al. (2009) cover the mechanisms underlying the beneficial effects of resveretrol in protection against cancer. These reviews are complimented by three key original articles focusing on endogenous mechanisms of weight control involving endocannabinoids (Izzo et al., 2009), a circulating protein, the soluble leptin receptor (Zhang & Scarpace, 2009) and a treatment, zinc plus cyclo-(His-Pro) (CHP), known to increase insulin metabolism (Song et al., 2009).

This themed section of BJP includes 11 reviews on the biology of G‐protein coupled receptors (GPCRs) and the drug targets that these present, 21 research papers on the pharmacology of a range of GPCRs and Commentaries on four of the papers. Areas reviewed include molecular interactions, particular in respect of hetero‐dimerisation between receptors and other membrane‐located proteins and other key signalling molecules including cAMP and G12/13 proteins and recently de‐orphanised receptors including the Neuromedins U & S and the Free Fatty Acid receptors FFA2 & FFA3. The research papers cover the pharmacology of a range of agents acting at GPCRs, including adrenoceptors, purinoceptors, 5HT, opioid, cannabinoid & PAR‐2 receptors. A group of papers is concerned with the interesting and rapidly developing pharmacology of drugs acting at β 2 ‐adrenoceptors. The reach of GPCRs is illustrated by the range of physiological systems and therapeutic applications involved, including pain, cancer, cardiovascular, gastrointestinal, visual and respiratory and central nervous systems.

The alpha1A-adrenoceptor (AR) mediates vasoconstriction in mouse small mesenteric arteries, but the alpha1B-AR and/or alpha1D-AR may also contribute to the contractile response in these arteries. In the alpha1AB-knockout (KO), where only the alpha1D-AR remains, functional studies have been performed only in the heart. The present study examined the agonist-induced contractile responses in small mesenteric arteries of the alpha1AB-KO and wild type (WT) mouse. Methods: Double knockout alpha1AB -/- mice were generated as previously described. First order mesenteric arteries were dissected from male, four-month old alpha1ABKO and WT control C57Bl/6J mice. 2 mm rings of artery were mounted in 4-chamber wire myographs. Cumulative concentration response curves were constructed in half log increments (1 nM-100 microM) to: the nonselective alpha1-AR agonist, phenylephrine; the alpha1A-AR selective agonist, A-61603; and the non-adrenergic agonist, 5-hydroxytryptamine. Results: Phenylephrine produced concentration-dependent contractions in both mouse strains (Table). In the alpha1AB-KO, the maximum response was significantly reduced but sensitivity was significantly higher, compared to the WT mouse. A-61603 produced concentration dependent contractions in the WT mouse but both maximum response and sensitivity to A-61603 were significantly lower in the alpha1AB-KO. 5-hydroxytryptamine had similar potency in the alpha1AB-KO and WT mouse. Conclusion: This study has examined functional responses in the vasculature of the alpha1AB-KO for the first time. The non-adrenergic response was comparable in the WT mouse and alpha1AB-KO, suggesting that any difference observed in the alpha1-AR-mediated responses was not due to a reduction in the overall contractility of the arteries. Based on the high efficacy of A-61603 in the WT mouse, this study confirms that alpha1-ARmediated contractions in small mesenteric arteries are predominantly mediated by the alpha1A-subtype of AR. The adrenergic responses in the alpha1AB-KO indicate that the alpha1D-AR mediates a contractile response in small mesenteric arteries and, therefore, suggest that the alpha1D-AR contributes to the vasoconstriction of resistance arteries in the WT mouse, consistent with a potential role for the alpha1D-AR in blood pressure regulation.

AbstractBackground and Purpose: Conventionally, the architecture of the artery wall is based upon the close-packed smooth muscle cells, endothelial and adventitial cells in both sides of internal elastic lamina (IEL). However, the adventitia and endothelium are now viewed as key players in vascular growth and repair. Recent work raises fundamental questions about the cellular heterogeneity of arteries, time course, triggering of normal and pathological re-modeling.Materials and Methods: Twelve wild type mice were employed. After killing with CO2 inhalation, dissected mesenteric arteries were removed and cleaned with adipose tissue. Arteries were mounted in the perfusion pressure myograph under normal pressure (70mmHg) in Kreb’s solution, which bubbled with 95% O2 and 5% CO2 to pH 7.4, at 37°C. After staining with fluorescent ligands (Syto 13) for nuclei and (DIO 1µM) for cytoplasm, arteries were scanned with the Laser Scanning Co focal Microscopy (LSCM) under (488nm/515nm), (484nm/501nm) and (543nm/580nm) Argon-Helium ion laser wavelength.Results: Three dimensional images of computer observation suggest that there may be a close relationship between the helical organization of smooth muscle cells and the underlying pattern of endothelial cells (myoendothelial connection).Conclusion: Tight junctions between cells must be broken and remade during the remodeling process. This suggests a carefully controlled defensive structure for intra-cellular connections, that is capable of withstanding the acute stresses of normal function, but which must be capable of modification to adapt to a new state, when the bio-physical conditions dictate. Endothelial mosaicism related to spiral arrangements of underlying smooth muscle cells, are associated with the functional cell connections. Taken together, these issues provide an exciting new phase in understanding the physiological modeling of the vascular wall, producing a new view of the dynamic nature of vascular structure.Key words: Myoedothelial Connections, Remodeling, Mesenteric Arteries, Internal Elastic Lamina, Fluorescent StainingJ Mazand Univ Med Sci 2008; 18(64): 60-70 (Persian)

1 It has been demonstrated that nerve-evoked contractions of the rat vas deferens involve alpha(1D)-adrenoceptors. Definitive evidence for a similar alpha(1D)-adrenoceptor-mediated response in mouse vas deferens has been more difficult to obtain. In this study, we have used alpha(1D)-adrenoceptor knockout (alpha(1D)-KO) mice to aid in the pharmacological characterization. 2 Mouse whole vas deferens was stimulated with a single pulse every 5 min. Once a stable response had been obtained, vehicle or antagonist was administered cumulatively at 5-min intervals and a response to stimulation obtained 5 min later. Cumulative concentration-response curves were also obtained for noradrenaline. 3 In vas deferens from alpha(1D)-KO mice, the contractile response to low concentrations of noradrenaline and the contractile response to a single stimulus were significantly reduced as compared to wild type (WT). 4 The alpha(1D)-adrenoceptor selective antagonist, BMY 7378, produced a concentration-dependent inhibition of single pulse-evoked contractions of vas deferens from WT and alpha(1D)-KO mice. BMY 7378 was significantly less potent in inhibiting stimulation-evoked contractions in vas deferens from alpha(1D)-KO mice. 5 It is concluded that alpha(1D)-adrenoceptors mediate a component of nerve- and agonist-evoked contractions of the vas deferens of WT mice.

This themed issue of the British Journal of Pharmacology has been compiled and edited by Ian McGrath, Regius Professor of Physiology at University of Glasgow and David Cowan, Director of the Drug Control Centre at King's College London. It contains 11 articles covering the mechanisms of action of the major groups of drugs used illicitly in sport. The articles, written by experts in how drugs work, set out where drugs can or cannot affect sporting performance, how this relates to their legitimate medicinal use, their other detrimental effects and how they can be detected. Publication coincides with Olympic year, when sport is highlighted in the public mind and much speculation is made concerning the use of drugs. The articles provide a framework of expert, accurate knowledge to inform and facilitate these debates and to help to overcome the ill-informed and dangerous anecdotal information by which sports men and women are persuaded to misuse drugs in the mistaken belief that this will improve their performance without present or future ill effects. A unique article is included by the Spedding brothers, Mike with a long career in drug discovery and Charlie, the 1984 Los Angeles Olympic Marathon Bronze Medallist and still the English National Marathon record holder. From their unique experience, they describe the insidious and unfair way that drug-assisted performance undermines the ethos of sport and endangers the vital place of sport in maintaining the health of the population.