| 1. |
- Fridlund, Bengt, et al.
(author)
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Essentials of Nursing Care in Randomized Controlled Trials of Nurse-Led Interventions in Somatic Care : A Systematic Review
- 2014
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In: Open Journal of Nursing. - Irvine : Scientific Research Publishing. - 2162-5336 .- 2162-5344. ; 4:3, s. 181-197
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Research review (peer-reviewed)abstract
- Background: Nursing practice has to contribute to evidence pointing out why there is a need for more nurse-designed randomized control trials (RCTs) focusing on evidence-based practice (EBP). How far this EBP has progressed in different health aspects is usually established by systematic reviews of RCTs. Nurse-led RCTs exist but no study has addressed the essentials of nursing care. Aim: The aim was therefore to determine the essentials of nurses’ interventions by means of nurse-led RCTs in somatic care focusing on the stated context, goals, content, strategies as well as the nurse’s role related to effectiveness. Methods: A systematic review was realized according to Cochrane review assumptions to identify, appraise and synthesize all empirical evidence meeting pre-specified eligibility criteria. The PRISMA statement guided the data extraction process (n = 55) from PubMed and CINAHL. Results: Of the RCTs in somatic care, 71% showed a positive effectiveness of nurse-led interventions, of which the nurse had a significant role with regard to being the main responsible in 67% of the studies. Also, 47% of the RCTs presented a theoretical standpoint related to the nurse-led interventions and most prominent were international evidence-based guidelines. Goals were found to have either a patient-centered or a professional-centered ambition. Strategies were based on patient-directed initiatives, nurse-patient-directed initiatives or nurse-directed initiatives, while contents were built upon either a patient-nurse interaction or a nursing management plan. Conclusions: This review underlines the necessity of a holistic view of a person, as nurse-led RCTs comprising a patient-centered ambition, patient-directed initiative and patient-nurse interaction plan showed beneficial nursing care effectiveness, particularly if theory-based. In a nurse-led RCT, a basic theoretical perspective is advantageous as well as to elucidate the role of the nurse in relation to the estimated effects.
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| 2. |
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| 3. |
- Ali, Mina, et al.
(author)
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The multiple myeloma risk allele at 5q15 lowers ELL2 expression and increases ribosomal gene expression
- 2018
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In: Nature communications. - : Springer Science and Business Media LLC. - 2041-1723. ; 9:1, s. 1649-
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Journal article (peer-reviewed)abstract
- Recently, we identified ELL2 as a susceptibility gene for multiple myeloma (MM). To understand its mechanism of action, we performed expression quantitative trait locus analysis in CD138+ plasma cells from 1630 MM patients from four populations. We show that the MM risk allele lowers ELL2 expression in these cells (Pcombined = 2.5 × 10−27; βcombined = −0.24 SD), but not in peripheral blood or other tissues. Consistent with this, several variants representing the MM risk allele map to regulatory genomic regions, and three yield reduced transcriptional activity in plasmocytoma cell lines. One of these (rs3777189-C) co-locates with the best-supported lead variants for ELL2 expression and MM risk, and reduces binding of MAFF/G/K family transcription factors. Moreover, further analysis reveals that the MM risk allele associates with upregulation of gene sets related to ribosome biogenesis, and knockout/knockdown and rescue experiments in plasmocytoma cell lines support a cause–effect relationship. Our results provide mechanistic insight into MM predisposition.
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| 4. |
- Amisten, Stefan, et al.
(author)
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Increased risk of acute myocardial infarction and elevated levels of C-reactive protein in carriersof the Thr-87 variant of the ATP receptor P2Y11.
- 2007
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In: European Heart Journal. - : Oxford University Press (OUP). - 1522-9645 .- 0195-668X. ; 28:1, s. 13-18
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Journal article (peer-reviewed)abstract
- Aims Extracellular ATP acting on the P2Y(11) receptor regulates inflammatory cells. We hypothesized that polymorphisms in the receptor could influence the risk of acute myocardial infarction (AMI). Methods and results In the Malmo diet and cancer AMI case-control study (n = 3732) the P2Y(11) gene Thr-87 polymorphism was present in 19.8% of the controls and 22.9% in AMI patients (OR 1.21; P = 0.03). Stronger associations were found in patients with family history (FH) of AMI, 1.32; early-onset (EO) AMI, 1.43; or EO AMI combined with FH, 1.50; supporting a genetic mechanism. The Thr-87 homozygotes had an even greater risk of AMI, 1.94 (P = 0.04); and 2.48 in the EO AMI subgroup, suggesting a genetic dosage effect. In the cardiovascular risk factor group (n = 6055), 21.3% carried the Thr-87 allele. C-reactive protein was elevated in Thr-87 carriers: 1.6 mg/L vs. 1.3 mg/L (P = 0.001). No difference was seen for blood pressure, lipids, body mass index, smoking, or diabetes mellitus. Conclusion The common Ala-87-Thr polymorphism of the P2Y(11) receptor is associated with AMI and increased levels of C-reactive protein. We hypothesize that an inflammatory mechanism might be involved. The P2Y(11) receptor is a promising new drug target in the prevention of AMI.
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| 5. |
- Balogh, Johanna, et al.
(author)
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Phospholipase C and cAMP-dependent positive inotropic effects of ATP in mouse cardiomyocytes via P2Y(11)-like receptors.
- 2005
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In: Journal of Molecular and Cellular Cardiology. - : Elsevier BV. - 1095-8584 .- 0022-2828. ; 39:2, s. 223-230
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Journal article (peer-reviewed)abstract
- ATP is released as a cotransmitter together with catecholamines from sympathetic nerves. In the heart ATP has been shown to cause a pronounced positive inotropic effect and may also act in synergy with β-adrenergic agonists to augment cardiomyocyte contractility. The aim of the present study was to investigate the inotropic effects mediated by purinergic P2 receptors using isolated mouse cardiomyocytes. Stable adenine nucleotide analogs were used and the agonist rank order for adenine nucleotide stimulation of the mouse cardiomyocytes was AR-C67085 > ATPγS > 2-MeSATP >>> 2-MeSADP = 0, that fits the agonist profile of the P2Y11 receptor. ATPγS induced a positive inotropic response in single mouse cardiomyocytes. The response was similar to that for the β1 receptor agonist isoproterenol. The most potent response was obtained using AR-C67085, a P2Y11 receptor agonist. This agonist also potentiated contractions in isolated trabecular preparations. The adenylyl cyclase blocker (SQ22563) and phospholipase C (PLC) blocker (U73122) demonstrated that both pathways were required for the inotropic response of AR-C67085. A cAMP enzyme immunoassay confirmed that AR-C67085 increased cAMP in the cardiomyocytes. These findings are in agreement with the P2Y11 receptor, coupled both to activation of IP3 and cAMP, being a major receptor for ATP induced inotropy. Analyzing cardiomyocytes from desmin deficient mice, Des–/–, with a congenital cardiomyopathy, we found a lower sensitivity to AR-C67085, suggesting a down-regulation of P2Y11 receptor function in heart failure. The prominent action of the P2Y11 receptor in controling cardiomyocyte contractility and possible alterations in its function during cardiomyopathy may suggest this receptor as a potential therapeutic target. It is possible that agonists for the P2Y11 receptor could be used to improve cardiac output in patients with circulatory shock and that P2Y11 receptor antagonist could be beneficial in patients with congestive heart failure (CHF).
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| 6. |
- Bergdahl, Andreas, et al.
(author)
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Plasticity of TRPC expression in arterial smooth muscle: correlation with store-operated Ca2+ entry.
- 2005
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In: American Journal of Physiology: Cell Physiology. - : American Physiological Society. - 1522-1563 .- 0363-6143. ; 288:4, s. 872-880
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Journal article (peer-reviewed)abstract
- Loss of the smooth muscle contractile phenotype is critical in atherosclerosis and in restenosis after angioplasty, but its early signals are incompletely understood. In this study, we have explored the role of transient receptor potential canonical (TRPC) proteins, which have been suggested to mediate store-operated Ca2+ entry (SOCE). Contractility of rat cerebral arteries in organ culture is preserved for several days, whereas SOCE is increased. In correlation with this increase is that nifedipine-insensitive whole cell current, activated by depletion of intracellular Ca2+ stores, was increased by 50% in cells isolated from arteries cultured for 3 days. TRPC1 and TRPC6 mRNA were more than fivefold increased in cells isolated after organ culture, whereas TRPC3 was decreased. Immunofluorescent staining and/or Western blotting of arteries and isolated cells showed upregulation of TRPC1 and TRPC6 proteins during organ culture. In intact arteries, TRPC4 expression correlated with the amount of endothelium present. Ca2+ addition after store depletion caused a contraction in cultured, but not in freshly dissected, arteries. A polyclonal TRPC1 antibody directed against an extracellular epitope inhibited this contraction by approximately 50%. To investigate the basis of the TRPC upregulation and assess its possible clinical significance, segments of human internal mammary artery were organ cultured for 24 h and then exposed to balloon dilatation in vitro, followed by further culturing for up to 48 h. After dilatation, TRPC1 and TRPC6 mRNA were progressively increased compared with undilated control segments. The results of this study indicate that vascular injury enhances plasticity in TRPC expression, that TRPC expression correlates with cellular Ca2+ handling, and that TRPC1 is a subunit of upregulated store-operated Ca2+ channels.
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| 7. |
- Braun, Oscar, et al.
(author)
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Residual platelet ADP reactivity after clopidogrel treatment is dependent on activation of both the unblocked P2Y(1) and the P2Y (12) receptor and is correlated with protein expression of P2Y (12).
- 2007
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In: Purinergic Signalling. - : Springer Science and Business Media LLC. - 1573-9546 .- 1573-9538. ; 3:3, s. 195-201
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Journal article (peer-reviewed)abstract
- Two ADP receptors have been identified on human platelets: P2Y(1) and P2Y(12). The P2Y(12) receptor blocker clopidogrel is widely used to reduce the risks in acute coronary syndromes, but, currently, there is no P2Y(1) blocker in clinical use. Evidence for variable responses to clopidogrel has been described in several reports. The mechanistic explanation for this phenomenon is not fully understood. The aim of this study was to examine mechanisms responsible for variability of 2MeS-ADP, a stable ADP analogue, induced platelet reactivity in clopidogrel-treated patients. Platelet reactivity was assessed by flow cytometry measurements of P-selectin (CD62P) and activated GpIIb/IIIa complex (PAC-1). Residual 2MeS-ADP activation via the P2Y(12) and P2Y(1) receptors was determined by co-incubation with the selective antagonists AR-C69931 and MRS2179 in vitro. P2Y(1) and P2Y(12) receptor expression on both RNA and protein level were determined, as well as the P2Y(12) H1 or H2 haplotypes. Our data suggest that the residual platelet activation of 2MeS-ADP after clopidogrel treatment is partly due to an inadequate antagonistic effect of clopidogrel on the P2Y(12) receptor and partly due to activation of the P2Y(1) receptor, which is unaffected by clopidogrel. Moreover, a correlation between increased P2Y(12) protein expression on platelets and decreased response to clopidogrel was noticed, r(2)=0.43 (P<0.05). No correlation was found between P2Y(12) mRNA levels and clopidogrel resistance, indicating post-transcriptional mechanisms. To achieve additional ADP inhibition in platelets, antagonists directed at the P2Y(1) receptor could be more promising than the development of more potent P2Y(12) receptor antagonists.
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| 8. |
- Ekvall-Hansson, Eva, et al.
(author)
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Satisfaction with rehabilitation in relation to self-perceived quality of life and function among patients with stroke - a 12 month follow-up.
- 2013
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In: Scandinavian Journal of Caring Sciences. - : Wiley. - 1471-6712 .- 0283-9318. ; 27:2, s. 373-379
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Journal article (peer-reviewed)abstract
- Scand J Caring Sci; 2012 Satisfaction with rehabilitation in relation to self-perceived quality of life and function among patients with stroke - a 12 month follow-up Background and Purpose: Stroke causes complex disability and function, and perceived quality of life has been shown to correlate with satisfaction with care as well as with life in general among stroke patients. The aim of this study was to study the relation of satisfaction with how rehabilitation was provided with self-perceived quality of life, self-perceived function and rehabilitation received, 12 months after the incidence. Method: The subjects were assessed 12 months after the onset of stroke. The Barthel index was used to measure function, and the EuroQol-5D to measure quality of life. To measure satisfaction with how rehabilitation was provided, a questionnaire from the Swedish Stroke Register was used. Results: Two hundred and eighty-three patients participated in the follow-up, 137 women and 146 men, aged between 42 and 95 years (mean age 75.2, SD 11.8). For the majority of patients rehabilitation was initiated at in-hospital care (directly after onset). One hundred and sixty-eight patients considered that rehabilitation was well provided for. Sixty-six regarded that the rehabilitation was only partly provided for and 35 that it was not provided for at all. High value on Barthel Index was associated with satisfaction with how rehabilitation was provided for (OR 2.81). Also, rehabilitation on three or more levels was negatively associated with satisfaction with rehabilitation provision (OR 0.24) and so was being male (OR 0.49). Conclusion: In this study, patients with higher values on Barthel Index were more satisfied with how rehabilitation was provided for. However, male patients and patients who received rehabilitation on three or more levels of care were less satisfied. Given the assumption that patients with more severe dysfunction after stroke are being rehabilitated on more levels, this might imply that it is not the amount of rehabilitation that gives satisfaction but the patients self-perceived function after rehabilitation.
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| 9. |
- Fridlund, Bengt, et al.
(author)
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Essentials of teamcare in randomized controlled trials of multidisciplinary or interdisciplinary interventions in somatic care : A systematic review
- 2015
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In: Open Journal of Nursing. - : Scientific Research Publishing. - 2162-5336 .- 2162-5344. ; 5:12, s. 1089-1101
-
Research review (peer-reviewed)abstract
- Background: Teamcare should, like all patient care, also contribute to evidence-based practice (EBP). Randomized controlled trials (RCTs) focusing on teamcare have been performed but no study has addressed its essentials. How far this EBP has progressed in different health aspects is generally established in systematic reviews of RCTs.Aim: The aim is to determine the essentials of teamcare including the nurse profession in RCTs of multi- or interdisciplinary interventions in somatic care focusing on the stated context, goals, strategies, content as well as effectiveness of quality of care.Methods: A systematic review was performed according to Cochrane review assumptions to identify, appraise and synthesize all empirical evidence meeting pre-specified eligibility criteria. The PRISMA statement guided the data selection process of 27 articles from PubMed and CINAHL.Results: Eighty-five percent of RCTs in somatic care showed a positive effectiveness of teamcare interventions, of which interdisciplinary ones showed a greater effectiveness compared with the multidisciplinary approach (100% vs 76%). Also theory-based RCTs presented higher positive effectiveness (85%) compared with non-theory-based RCTs (79%). The RCTs with positive effectiveness showed greater levels for professional-centered ambition in terms of goals and for team-directed initiatives in terms of strategy, and a significantly higher level for patient-team interaction plans in terms of content was shown.Conclusions: Teamcare RCTs are still grounded in the multidisciplinary approach having a professional-centered ambition while interdisciplinary approaches especially those that are theory-based appear to be essential with regard to positive effectiveness and preferable when person-centered careis applied.
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| 10. |
- Jonsson, Stefan, et al.
(author)
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Identification of sequence variants influencing immunoglobulin levels
- 2017
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In: Nature Genetics. - : Springer Science and Business Media LLC. - 1546-1718 .- 1061-4036. ; 49:8, s. 1182-1191
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Journal article (peer-reviewed)abstract
- Immunoglobulins are the effector molecules of the adaptive humoral immune system. In a genome-wide association study of 19,219 individuals, we found 38 new variants and replicated 5 known variants associating with IgA, IgG or IgM levels or with composite immunoglobulin traits, accounted for by 32 loci. Variants at these loci also affect the risk of autoimmune diseases and blood malignancies and influence blood cell development. Notable associations include a rare variant at RUNX3 decreasing IgA levels by shifting isoform proportions (rs188468174[C>T]: P = 8.3 × 10(-55), β = -0.90 s.d.), a rare in-frame deletion in FCGR2B abolishing IgG binding to the encoded receptor (p.Asn106del: P = 4.2 × 10(-8), β = 1.03 s.d.), four IGH locus variants influencing class switching, and ten new associations with the HLA region. Our results provide new insight into the regulation of humoral immunity.
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| 11. |
- Kim, HS, et al.
(author)
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Methanocarba modification of uracil and adenine nucleotides: High potency of northern ring conformation at P2Y(1), P2Y(2), P2Y(4), and P2Y(11) but not P2Y(6) receptors
- 2002
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In: Journal of Medicinal Chemistry. - : American Chemical Society (ACS). - 1520-4804 .- 0022-2623. ; 45:1, s. 208-218
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Journal article (peer-reviewed)abstract
- The potency of nucleotide antagonists at P2Y(1) receptors was enhanced by replacing the ribose moiety with a constrained carbocyclic ring (Nandanan, et al. J. Med. Chem. 2000, 43, 829842). We have now synthesized ring-constrained methanocarba analogues (in which a fused cyclopropane moiety constrains the pseudosugar ring) of adenine and uracil nucleotides, the endogenous activators of P2Y receptors. Methanocarba-adenosine 5'-triphosphate (ATP) was fixed in either a Northern (N) or a Southern (S) conformation, as defined in the pseudorotational cycle. (N)-Methanocarba-uridine was prepared from the 1-amino-pseudosugar ring by treatment with beta-ethoxyacryloyl cyanate and cyclization to form the uracil ring. Phosphorylation was carried out at the 5'-hydroxyl group through a multistep process: Reaction with phosphoramidite followed by oxidation provided the 5'-monophosphates, which then were treated with 1,1'-carbonyldiimidazole for condensation with additional phosphate groups, The ability of the analogues to stimulate phospholipase C through activation of turkey P2Y(1) or human P2Y(1), P2Y(2), P2Y(4), P2Y(6), and P2Y(11) receptors stably expressed in astrocytoma cells was measured. At recombinant human P2Y(1) and P2Y(2) receptors, (N)-methanocarba-ATP was 138- and 41-fold, respectively, more potent than racemic (S)-methanocarba-ATP as an agonist. (N)methanocarba-ATP activated P2Y(11) receptors with a potency similar to ATP. (N)-Methanocarba-uridine 5'-triphosphate (UTP) was equipotent to UTP as an agonist at human P2Y2 receptors and also activated P2Y(4) receptors with an EC50 of 85 nM. (N)-Methanocarba-uridine 5'-diphosphate (UDP) was inactive at the hP2Y(6) receptor. The vascular effects of (N)-methanocarba-UTP and (N)-methanocarba-UDP were studied in a model of the rat mesenteric artery, The triphosphate was more potent than UTP in inducing a dilatory P2Y(4) response (pEC(50) = 6.1 +/- 0.2), while the diphosphate was inactive as either an agonist or antagonist in a P2Y(6) receptor-mediated contractile response. Our results suggest that new nucleotide agonists may be designed on the basis of the (N) conformation that favors selectivity for P2Y(1), P2Y(2), P2Y(4), and P2Y(11) receptors.
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| 12. |
- Mitchell, Jonathan S., et al.
(author)
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Genome-wide association study identifies multiple susceptibility loci for multiple myeloma
- 2016
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In: Nature Communications. - : Springer Science and Business Media LLC. - 2041-1723. ; 7
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Journal article (peer-reviewed)abstract
- Multiple myeloma (MM) is a plasma cell malignancy with a significant heritable basis. Genome-wide association studies have transformed our understanding of MM predisposition, but individual studies have had limited power to discover risk loci. Here we perform a meta-analysis of these GWAS, add a new GWAS and perform replication analyses resulting in 9,866 cases and 239,188 controls. We confirm all nine known risk loci and discover eight new loci at 6p22.3 (rs34229995, P = 1.31 x 10(-8)), 6q21 (rs9372120, P = 9.09 x 10(-15)), 7q36.1 (rs7781265, P = 9.71 x 10(-9)), 8q24.21 (rs1948915, P = 4.20 x 10(-11)), 9p21.3 (rs2811710, P = 1.72 x 10(-13)), 10p12.1 (rs2790457, P = 1.77 x 10(-8)), 16q23.1 (rs7193541, P = 5.00 x 10(-12)) and 20q13.13 (rs6066835, P = 1.36 x 10(-13)), which localize in or near to JARID2, ATG5, SMARCD3, CCAT1, CDKN2A, WAC, RFWD3 and PREX1. These findings provide additional support for a polygenic model of MM and insight into the biological basis of tumour development.
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| 13. |
- Pertesi, Maroulio, et al.
(author)
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Essential genes shape cancer genomes through linear limitation of homozygous deletions
- 2019
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In: Communications Biology. - : Springer Science and Business Media LLC. - 2399-3642. ; 2:1
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Journal article (peer-reviewed)abstract
- The landscape of somatic acquired deletions in cancer cells is shaped by positive and negative selection. Recurrent deletions typically target tumor suppressor, leading to positive selection. Simultaneously, loss of a nearby essential gene can lead to negative selection, and introduce latent vulnerabilities specific to cancer cells. Here we show that, under basic assumptions on positive and negative selection, deletion limitation gives rise to a statistical pattern where the frequency of homozygous deletions decreases approximately linearly between the deletion target gene and the nearest essential genes. Using DNA copy number data from 9,744 human cancer specimens, we demonstrate that linear deletion limitation exists and exposes deletion-limiting genes for seven known deletion targets (CDKN2A, RB1, PTEN, MAP2K4, NF1, SMAD4, and LINC00290). Downstream analysis of pooled CRISPR/Cas9 data provide further evidence of essentiality. Our results provide further insight into how the deletion landscape is shaped and identify potentially targetable vulnerabilities.
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| 14. |
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| 15. |
- Went, M, et al.
(author)
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Identification of multiple risk loci and regulatory mechanisms influencing susceptibility to multiple myeloma
- 2018
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In: Nature communications. - : Springer Science and Business Media LLC. - 2041-1723. ; 9:1, s. 3707-
-
Journal article (peer-reviewed)abstract
- Genome-wide association studies (GWAS) have transformed our understanding of susceptibility to multiple myeloma (MM), but much of the heritability remains unexplained. We report a new GWAS, a meta-analysis with previous GWAS and a replication series, totalling 9974 MM cases and 247,556 controls of European ancestry. Collectively, these data provide evidence for six new MM risk loci, bringing the total number to 23. Integration of information from gene expression, epigenetic profiling and in situ Hi-C data for the 23 risk loci implicate disruption of developmental transcriptional regulators as a basis of MM susceptibility, compatible with altered B-cell differentiation as a key mechanism. Dysregulation of autophagy/apoptosis and cell cycle signalling feature as recurrently perturbed pathways. Our findings provide further insight into the biological basis of MM.
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| 16. |
- Wihlborg, Anna-Karin, et al.
(author)
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2,2 '-nitrophenylisatogen potentiates P2X(1) receptor mediated vascular contraction and blood pressure elevation
- 2003
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In: Drug Development Research (Proceedings of the Seventh International Symposium on Adenosine and Adenine Nucleotides - Part 2). - : Wiley. - 1098-2299 .- 0272-4391. ; 59:1, s. 82-87
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Conference paper (peer-reviewed)abstract
- The objective of this research was to examine the effects of chemical compounds with possible P2 receptor modulating effects and to characterize the potentiating effects of 2,2'-nitrophenylisatogen (NPI) on P2X(1) receptors in vitro and in vivo. Chemical compounds were tested in an in vitro pharmacological assay using vascular segments from the rat mesenteric artery stimulated by P2 receptor-specific agonists. Contractions were expressed as a percentage of 60 mM K+-induced contractions. Blood pressure was evaluated in pithed rats. NPI (30 muM) added 15 min before addition of the P2X(1) receptor-specific agonist alphabeta-MeATP increased the maximum vasoconstriction from 23% to 49% (an increase of 113%). Furthermore, NPI prevented the desensitization of repeated UP-MeATP contractions. Related compounds were examined, and 2-(3-methoxy-phenyl)-1-oxy-indol-3-one (MPI) had similar effects as NPI, but several others lacked effect. NPI had no effect on ADPbetaS (P2Y(1)) or acetylcholine-mediated vasodilatation, nor on UTP (P2Y(2/4)), UDP (P2Y(6)), or noradrenaline-mediated contractions. In pithed rats, the blood pressure response to 50 nmol/kg-infusion of alphabeta-MeATP was increased from 50+/-6 to 63+/-5 mmHg (P < 0.05), but had no effect on basal blood pressure or on the cardiovascular response to preganglionic nerve stimulation. In conclusion, NPI and MPI potentiates P2X(1) receptor vascular contractions in vitro and (NPI) blood pressure effects in vivo. It is possible that the effect is mediated by an inhibition of P2X(1) receptor desensitization. Drug Dev. Res. (C) Wiley-Liss, Inc.
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| 17. |
- Wihlborg, Anna-Karin, et al.
(author)
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ADP Receptor P2Y12 Is Expressed in Vascular Smooth Muscle Cells and Stimulates Contraction in Human Blood Vessels.
- 2004
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In: Arteriosclerosis, Thrombosis and Vascular Biology. - 1524-4636. ; 24:10, s. 1810-1815
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Journal article (peer-reviewed)abstract
- Objective - ADP plays an important role in platelet aggregation by activating P2Y(12) receptors. We assessed the hypothesis that P2Y(12) receptors are expressed in vascular smooth muscle cells (VSMC). Methods and Results - P2Y(12) receptor mRNA was found to have a high expression among the P2 receptors in human VSMC, significantly higher than the other 2 ADP receptors (P2Y(1) and P2Y(13), real-time polymerase chain reaction). Western blots gave a band of 50 kD, similar to that in platelets. To unmask a P2Y(12) receptor-mediated vasoconstriction by simulating the in vivo situation, vessels were precontracted to a submaximal level. 2-MeSADP stimulated contractions in vessel segments from internal mammary artery (IM), IM branches and small veins (E-max = 15 +/- 6% of 60 mmol/L K+ contraction, pEC(50) = 5.6 +/- 0.6, E-max = 21 +/- 1%, pEC(50) = 6.8 +/- 0.1, and E-max = 48 +/- 9%, pEC(50) = 6.6 +/- 0.4). The selective P2Y(12) antagonist AR-C67085 blocked 2-MeSADP contractions. The contraction was not reduced in patients using clopidogrel, a drug inhibiting ADP-induced platelet aggregation by blocking the P2Y(12) receptor. This may be explained by the high instability of the active clopidogrel metabolite that never reaches the systemic circulation. Conclusion - ADP acting on P2Y(12) receptors not only is important for platelet activation but also stimulates vasoconstriction. Stable drugs with antagonistic effects on P2Y(12) receptors, affecting both platelets and VSMC, could be of double therapeutic benefit in their prevention of both thrombosis and vasospasm.
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| 18. |
- Wihlborg, Anna-Karin, et al.
(author)
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Extracellular nucleotides induce vasodilatation in human arteries via prostaglandins, nitric oxide and endothelium-derived hyperpolarising factor.
- 2003
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In: British Journal of Pharmacology. - : Wiley. - 1476-5381 .- 0007-1188. ; 138:8, s. 1451-1458
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Journal article (peer-reviewed)abstract
- 1. The present study was aimed at examining P2 receptor-mediated vasodilatation in human vessels. The isometric tension was recorded in isolated segments of the human left internal mammary artery branches precontracted with 1 muM noradrenaline. 2. Endothelial denudation abolished the dilator responses. 3. The selective P2Y1 agonist, 2-MeSADP, induced a potent vasodilatation (pEC50=6.9plusminus0.1). The P2Y1 antagonist of 10 muM, MRS 2216, shifted the 2-MeSADP concentration-response curve 1.1 log units to the right. The combined P2Y1 and P2X agonist, 2-MeSATP, stimulated a dilatation with a potency similar to that of 2-MeSADP. Furthermore, MRS 2216 had a similar antagonistic effect on both 2-MeSATP and 2-MeSADP indicating that P2X receptors do not mediate vasodilatation. 4. Both the P2Y2/4 agonist, UTPitalic gammaS and the P2Y6 agonist, UDPbetaS, stimulated potent dilatations (pEC50=7.8plusminus0.4 for UTPitalic gammaS and 8.4plusminus0.2 for UDPbetaS). 5. The 2-MeSADP-induced nitric oxide (NO)-mediated dilatation was studied in the presence of 10 muM indomethacin, 50 nM charybdotoxin and 1 muM apamin. The involvement of the endothelium-derived hyperpolarising factor (EDHF) was investigated in the presence of 0.1 mML-NOARG and indomethacin. The involvement of prostaglandins was investigated in the presence of L-NOARG, charybdotoxin and apamin. Both NO, EDHF and prostaglandins mediated 2-MeSADP dilatation with similar efficacy (Emax=25plusminus5% for NO, 25plusminus6% for EDHF and 27plusminus5% for prostaglandins). 6. In conclusion, extracellular nucleotides induce endothelium-derived vasodilatation in human vessels by stimulating P2Y1, P2Y2/4 and P2Y6 receptors, while P2X receptors are not involved. Endothelial P2Y receptors mediate dilatation by release of EDHF, NO and prostaglandins
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| 19. |
- Wihlborg, Anna-Karin
(author)
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Novel functions of cardiovascular P2 receptors
- 2004
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Doctoral thesis (other academic/artistic)abstract
- The aim of the thesis was to examine the expression and function of the extracellular nucleotide P2 receptors in the cardiovascular system. In the cardiovascular system nucleotides are released during shear stress, hypoxia, ischemia, from endothelial cells, smooth muscle cells, aggregating platelets, inflammatory cells and erythrocytes. We demonstrate that ATP, ADP, UTP and UDP induce vascular relaxation in human blood vessels stimulating P2Y1, P2Y2 and P2Y6 receptors on endothelial cells. ADP, acting on the P2Y1 receptor was the most potent vasodilator and the response was mediated via equal amounts of NO, EDHF and prostaglandins. We show that ADP gives contraction in human blood vessels and reveal functional expression of P2Y12 receptors on the VSMC. In vessels having an intact endothelium, ADP induces vasodilatation but a dysfunctional endothelium leads to ADP induced contraction. Stable drugs with antagonistic effects on P2Y12 receptors, affecting both platelets and VSMC, could be of double therapeutic benefit in their prevention of both thrombosis and vasospasm. Increased ATP release has been shown during cardiac ischemia. We found increased levels of UTP in patients with myocardial infarction and the amounts correlated to the ATP level (1:10). ATP, UTP and UDP stimulated potent inotropic effects acting on the heart muscle cells. The pyrimidine effects were mediated via P2Y2/4 and P2Y6 receptors acting via PLC pathways. Expression of P2Y2, P2Y4 and P2Y6 was verified using real-time PCR. ATP induced inotropic effects mediated via two pathways, PLC and adenylyl cyclase pathway, suggesting a P2Y11-like receptor in mouse. Responses to UDP and a P2Y11 agonist were decreased in mice with cardiomyopathy. Antagonists for P2Y2/4, P2Y6 and P2Y11 receptors could be beneficial in the treatment of hypertension and heart failure. Finally, by designing and synthesizing new chemical compounds, two new P2X1 receptor potentiating substances were found. The clinical use of a P2X1 receptor potentiator could be to increase blood pressure in orthostatic hypotension, counteract urinary incontinence, or even male infertility.
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| 20. |
- Wihlborg, Anna-Karin, et al.
(author)
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Positive inotropic effects by uridine triphosphate (UTP) and uridine diphosphate (UDP) via P2Y(2) and P2Y(6) receptors on cardiomyocytes and release of UTP in man during myocardial infarction
- 2006
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In: Circulation Research. - 0009-7330. ; 98:7, s. 970-976
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Journal article (peer-reviewed)abstract
- The aim of this study was to examine a possible role for extracellular pyrimidines as inotropic factors for the heart. First, nucleotide plasma levels were measured to evaluate whether UTP is released in patients with coronary heart disease. Then, inotropic effects of pyrimidines were examined in isolated mouse cardiomyocytes. Finally, expression of pyrimidine-selective receptors ( a subgroup of the P2 receptors) was studied in human and mouse heart, using real time polymerase chain reaction, Western blot, and immunohistochemistry. Venous plasma levels of UTP were increased (57%) in patients with myocardial infarction. In electrically stimulated cardiomyocytes the stable P2Y(2/4) agonist UTP gamma S increased contraction by 52%, similar to beta(1)-adrenergic stimulation with isoproterenol (65%). The P2Y(6)-agonist UDP gamma S also increased cardiomyocyte contraction (35%), an effect abolished by the P2Y(6)-blocker MRS2578. The phospholipase C inhibitor U73122 inhibited both the UDP beta S and the UTP gamma S-induced inotropic effect, indicating an IP3-mediated effect via P2Y(6) receptors. The P2Y(14) agonist UDP-glucose was without effect. Quantification of mRNA with real time polymerase chain reaction revealed P2Y(2) as the most abundant pyrimidine receptor expressed in cardiomyocytes from man. Presence of P2Y(6) receptor mRNA was detected in both species and confirmed at protein level with Western blot and immunohistochemistry in man. In conclusion, UTP levels are increased in humans during myocardial infarction, giving the first evidence for UTP release in man. UTP is a cardiac inotropic factor most likely by activation of P2Y(2) receptors in man. For the first time we demonstrate inotropic effects of UDP, mediated by P2Y(6) receptors via an IP3-dependent pathway. Thus, the extracellular pyrimidines ( UTP and UDP) could be important inotropic factors involved in the development of cardiac disease.
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