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1.
Naunyn Schmiedebergs Arch Pharmacol ; 388(5): 557-64, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25678054

RESUMO

In a lipopolysaccharide (LPS)-induced rat model of sepsis (endotoxaemia), we previously demonstrated that pravastatin reduced microvascular inflammation via increased endothelial nitric oxide synthase III (NOSIII). This study aimed to determine whether atorvastatin, the most commonly used statin for lowering cholesterol, exerted beneficial pleiotropic effects via a similar mechanism. The mesenteric microcirculation of anaesthetised male Wistar rats (308 ± 63 g, n = 54) was prepared for fluorescent intravital microscopy. Over 4 h, animals received intravenous (i.v.) administration of either saline, LPS (150 µg kg(-1) h(-1)) or LPS + atorvastatin (200 µg kg(-1) s.c., 18 and 3 h before LPS), with/without the non-specific NOS inhibitor L-NG-Nitroarginine Methyl Ester (L-NAME) (10 µg kg(-1) h(-1)) or NOSII-specific inhibitor 1400 W (20 µg kg(-1) min(-1)). LPS decreased mean arterial blood pressure (MAP) (4 h, control 113 ± 20 mmHg; LPS 70 ± 23 mmHg), being reversed by atorvastatin (105 ± 3 mmHg) (p < 0.05). LPS also increased macromolecular leak measured after 100 mg kg(-1) of i.v FITC-BSA (arbitrary grey level adjacent to venules), which again was attenuated by atorvastatin (control 1.9 ± 4.0; LPS 12.0 ± 2.4; LPS + atorvastatin 4.5 ± 2.2) (p < 0.05). Furthermore, immunohistochemistry identified that atorvastatin decreased LPS-induced upregulation of endothelial cell NOSII expression, but NOSIII was unchanged in all groups. Atorvastatin improved MAP and reduced microvascular inflammation during endotoxaemia, associated with a reduction of pro-inflammatory NOSII. This differs from previous studies, whereby pravastatin increased expression of NOSIII. Thus preoperative statins have beneficial anti-inflammatory effects during endotoxaemia, but careful consideration must be given to the specific statin being used.


Assuntos
Anti-Inflamatórios não Esteroides/uso terapêutico , Atorvastatina/uso terapêutico , Endotoxemia/complicações , Microvasos/efeitos dos fármacos , Óxido Nítrico Sintase Tipo II/metabolismo , Vasculite/prevenção & controle , Animais , Atorvastatina/administração & dosagem , Permeabilidade Capilar/efeitos dos fármacos , Adesão Celular/efeitos dos fármacos , Endotélio Vascular/efeitos dos fármacos , Endotélio Vascular/enzimologia , Endotélio Vascular/fisiopatologia , Endotoxemia/enzimologia , Endotoxemia/fisiopatologia , Expressão Gênica/efeitos dos fármacos , Microscopia Intravital , Leucócitos/enzimologia , Leucócitos/fisiologia , Lipopolissacarídeos/toxicidade , Masculino , Microcirculação/efeitos dos fármacos , Microvasos/enzimologia , Óxido Nítrico Sintase Tipo II/genética , Ratos Wistar , Vasculite/induzido quimicamente , Vasculite/enzimologia , Vasculite/fisiopatologia
2.
Microvasc Res ; 81(3): 281-8, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-21354186

RESUMO

Sepsis may be modeled using lipopolysaccharide (LPS), which alters levels of nitric oxide (NO), synthesized via endothelial and inducible nitric oxide synthase (eNOS and iNOS). This study aimed to determine whether the Rho kinase (ROCK) inhibitor fasudil protected against LPS-induced (endotoxemia) macromolecular leak and leukocyte adhesion via NOS pathways. Male Wistar rats (283±8g, n=36) were anaesthetized with thiopental and the mesentery prepared for fluorescent intravital microscopy (IVM). Animals received either (i) LPS alone (150µg kg(-1) h(-1) i.v., n=6); (ii) fasudil (FAS, 3mg kg(-1) i.v., n=6) or (iii) fasudil (10mg kg(-1) i.v., n=6), immediately prior to LPS administration, (iv) fasudil (FAS, 3mg kg(-1) i.v., n=6) alone or (v) fasudil (FAS, 10mg kg(-1) i.v., n=6) alone, or (vi) saline alone (1ml kg(-1) h(-1) i.v, n=6) for 4h (240min). LPS increased macromolecular leak (cumulative normalized grey levels, arbitrary units) from post capillary venules (<40µm) and this was reduced by 3mg kg(-1) fasudil, however, 10mg kg(-1) was less effective (t=240min, control: 3.3±1.7; LPS: 15.1±2.0; LPS+3mg kg(-1) fasudil: 3.3±1.1 (p<0.05), LPS+10mg kg(-1) fasudil: 8.4±3.2 NS). The numbers of leukocytes adhering for >1min/100µm venule were reduced by fasudil (t=240min, control: 1.8±0.7; LPS: 7.0±1.0; LPS+3mg kg(-1) fasudil: 1.75±0.25, p<0.05; LPS+10mg kg(-1) fasudil: 1.8±0.8, p<0.05). Immunohistochemistry demonstrated that fasudil increased endothelial cell expression of eNOS during sepsis, and decreased LPS-induced up-regulation of iNOS. Inhibition of ROCK in rats increases eNOS and decreases iNOS during endotoxemia, concomitantly reducing microvascular inflammation. Thus, targeting the ROCK pathway during sepsis could have therapeutic potential for reducing inflammation via a NO dependent mechanism.


Assuntos
Endotoxemia/metabolismo , Microcirculação/fisiologia , Microvasos/metabolismo , Óxido Nítrico Sintase/metabolismo , Quinases Associadas a rho/metabolismo , 1-(5-Isoquinolinasulfonil)-2-Metilpiperazina/análogos & derivados , 1-(5-Isoquinolinasulfonil)-2-Metilpiperazina/farmacologia , Animais , Pressão Sanguínea/efeitos dos fármacos , Permeabilidade Capilar/efeitos dos fármacos , Adesão Celular/efeitos dos fármacos , Células Endoteliais/efeitos dos fármacos , Células Endoteliais/metabolismo , Endotoxemia/induzido quimicamente , Endotoxemia/fisiopatologia , Inflamação/induzido quimicamente , Inflamação/metabolismo , Inflamação/fisiopatologia , Leucócitos/efeitos dos fármacos , Leucócitos/metabolismo , Leucócitos/patologia , Lipopolissacarídeos/farmacologia , Masculino , Microcirculação/efeitos dos fármacos , Microvasos/efeitos dos fármacos , Microvasos/fisiopatologia , Óxido Nítrico/sangue , Óxido Nítrico Sintase Tipo II/metabolismo , Óxido Nítrico Sintase Tipo III/metabolismo , Inibidores de Proteínas Quinases/farmacologia , Ratos , Ratos Wistar , Circulação Esplâncnica/efeitos dos fármacos , Circulação Esplâncnica/fisiologia , Quinases Associadas a rho/antagonistas & inibidores
3.
Curr Med Res Opin ; 27(3): 559-67, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21222569

RESUMO

BACKGROUND/OBJECTIVE: The START study was a large general practice observational study involving 400 patients with migraine. Given the large sample size, a sub-analysis was planned to ascertain whether any patient characteristics/behaviors might help predict/explain the responses observed in this study, which demonstrated that almotriptan administered early when pain was mild significantly improved pain-related outcomes compared with non-early/non-mild treatment. METHODS: This pre-planned sub-analysis assessed the impact of predictors of patient satisfaction, medication history, delayed drug intake, etc. on the primary pain endpoints of the START study. RESULTS: Patients had previously tried an average of 2.5 drugs for migraine relief and were currently taking a mean of 1.4 drugs. Almotriptan had been tried by 21% of the sample and was still being used by 83% of this sub-group. Treatment satisfaction was higher in the subset of patients taking almotriptan than in almotriptan-naїve individuals (p < 0.001) and this may explain why this group had the highest continuation rate of all drugs evaluated. On completion of the study, patient satisfaction was higher in the early/mild treatment group than the non-early/non-mild group (p = 0.049). Many patients delayed taking almotriptan, despite being instructed otherwise. Patients reported that this was primarily because they believed that they should only take the medication in the case of a severe migraine attack and/or to ensure that the symptoms were definitely due to migraine headache. The limitations of the trial include its open, observational design, and the small number of individuals who managed to treat their migraine attack within 1 hour when it was still mild. CONCLUSIONS: Almotriptan was associated with increased patient satisfaction, particularly when taken early. Further action is required to increase patient compliance with early treatment regimens to improve clinical outcomes.


Assuntos
Transtornos de Enxaqueca/tratamento farmacológico , Dor/tratamento farmacológico , Satisfação do Paciente/estatística & dados numéricos , Triptaminas/uso terapêutico , Analgésicos/uso terapêutico , Quimioprevenção/métodos , Quimioprevenção/estatística & dados numéricos , Progressão da Doença , Humanos , Transtornos de Enxaqueca/diagnóstico , Transtornos de Enxaqueca/epidemiologia , Dor/diagnóstico , Dor/epidemiologia , Dor/prevenção & controle , Atenção Primária à Saúde , Prognóstico
4.
Expert Rev Neurother ; 10(10): 1505-17, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20945537

RESUMO

Almotriptan, a serotonin 5-HT 1B/1D agonist, was developed for the acute treatment of migraine with or without aura and has been available for 10 years. This article evaluates the wealth of experience that has been obtained with almotriptan, including large randomized clinical trials (RCTs) and post-marketing studies that more closely reflect everyday clinical practice. Initial RCTs required patients to take almotriptan when migraine pain was of moderate or severe intensity, and found that 12.5 mg provided optimal outcomes for both pain relief and tolerability. Almotriptan effectively improved 2-h pain-relief, reduced migraine-associated symptoms and demonstrated low recurrence rates. These findings were also shown in patient subgroups, such as adolescents and menstrual migraineurs. A secondary finding in these trials was that patients who took almotriptan early, when the pain was still mild, achieved better outcomes. This prompted the initiation of studies designed to assess the effect of almotriptan in early intervention. Open-label trials reported improvements in pain-free end points (2 h, 24 h), and subsequent RCTs confirmed these findings. Pharmacovigilance data from more than 100 million tablets dispensed worldwide have confirmed that almotriptan is associated with a low occurrence of adverse effects, which, in clinical trials, has been shown to be similar to that observed with placebo. The clinical evidence obtained and comparisons made over a decade of use have demonstrated that almotriptan is one of the more effective and fast-acting triptans available, with a placebo-like tolerability profile. This suggests that almotriptan is an excellent choice for patients requiring specific acute migraine treatment.


Assuntos
Transtornos de Enxaqueca/tratamento farmacológico , Agonistas do Receptor de Serotonina/efeitos adversos , Agonistas do Receptor de Serotonina/uso terapêutico , Triptaminas/farmacocinética , Triptaminas/uso terapêutico , Relação Dose-Resposta a Droga , Diagnóstico Precoce , Feminino , Humanos , Masculino , Vigilância de Produtos Comercializados , Ensaios Clínicos Controlados Aleatórios como Assunto , Recidiva , Agonistas do Receptor de Serotonina/farmacocinética , Fatores de Tempo , Resultado do Tratamento , Triptaminas/efeitos adversos
5.
Physiol Behav ; 101(4): 541-8, 2010 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-20705078

RESUMO

Products of the Doublecortin-Like Kinase (DCLK) gene are associated with cortical migration and hippocampal maturation during embryogenesis. However, the functions of those DCLK gene transcripts that encode kinases and are expressed during adulthood are incompletely understood. To elucidate potential functions of these DCLK gene splice variants we have generated and analyzed transgenic mice with neuronal over-expression of a truncated, constitutively active form of DCLK-short, designated δC-DCLK-short. Previously, we have performed an extensive molecular characterization of these transgenic δC-DCLK-short mice and established that a specific subunit of the GABA(A) receptor, which is involved in anxiety-related GABAergic neurotransmission, is down-regulated in the hippocampus. Here we show that δC-DCLK-short mRNA is highly expressed in the hippocampus, cortex and amygdala of transgenic mice. We provide evidence that the δC-DCLK-short protein is expressed and functional. In addition, we examined anxiety-related behavior in δC-DCLK-short mice in the elevated plus maze. Interestingly, δC-DCLK-short mice spend less time, move less in the open arms of the maze and show a reduction in the number of rim dips. These behaviors indicate that δC-DCLK-short mice display a more anxious behavioral phenotype.


Assuntos
Ansiedade/metabolismo , Encéfalo/metabolismo , Comportamento Exploratório/fisiologia , Proteínas Serina-Treonina Quinases/metabolismo , Tonsila do Cerebelo/metabolismo , Animais , Córtex Cerebral/metabolismo , Quinases Semelhantes a Duplacortina , Regulação da Expressão Gênica/fisiologia , Engenharia Genética/métodos , Hipocampo/metabolismo , Masculino , Aprendizagem em Labirinto/fisiologia , Camundongos , Camundongos Transgênicos , Fragmentos de Peptídeos , Proteínas Serina-Treonina Quinases/genética , RNA Mensageiro/análise , Distribuição Tecidual
6.
Lymphat Res Biol ; 7(3): 131-7, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19778200

RESUMO

BACKGROUND: The spleen has an important physiological role in maintaining blood volume; this study aimed to determine whether during pathophysiological circumstances, namely endotoxemia, the extrasplenic pathway is dysfunctional. We hypothesize that increased 'leakiness' of lymphatics in response to lipopolysaccharide (LPS) provides a route for loss of protein-rich fluid into third spaces and prevents the spleen from maintaining blood volume homeostasis. METHODS AND RESULTS: Male Wistar rats (200-280 g, n = 24) were anesthetized with thiopental (40-90 mg x kg(-1) x hr(-1), i.v.) to study the extrasplenic (vessels in mesentery adjoining the spleen) and ileal mesenteric microcirculation using fluorescently labeled albumin (66 KDa FITC-BSA, 0.02 g.100 g(-1), i.v.) with intravital microscopy. LPS (150 microg x kg(-1) x hr(-1) i.v.) induced constriction of rat extrasplenic venules (-14 +/- 2.4% from 40.4 +/- 7.8 microm, p < 0.05) and no change in arteriolar diameter (-4.6 +/- 4.7% from 32.6 +/- 4.3 microm). As the spleen is freely permeable to protein, a greater increase in venular versus arteriolar extrasplenic resistance increases intrasplenic capillary hydrostatic pressure, leading to fluid efflux into the lymphatics, draining the spleen. In agreement we report here increased extrasplenic venular resistance with LPS and lymphatic dilation to accommodate this fluid (13.5 +/- 6% from 18.5 +/- 4.8 microm, p < 0.05). However, the extrasplenic pathway then appeared to dysfunction, with macromolecular leak from extrasplenic venules (24.6 +/- 6.4%, p < 0.05) and lymphatics (12.1 +/- 3.4%, p < 0.05), indicated by increased interstitial FITC-BSA fluorescence. This was less than from ileal mesenteric venules (324 +/- 32%, p < 0.05). There was a concurrent decrease in mean arterial pressure (T(180): -15.1 +/- 6.9% from MAP of 130.3 +/- 8.8 mmHg at T(0), p < 0.05). CONCLUSION: Lymphatics are generally considered to demonstrate unidirectional and inward uptake of large molecules. However, during endotoxemia, we have demonstrated that extrasplenic lymphatics also allow the leakage of large protein molecules out into interstitial spaces. Fluid losses from extrasplenic lymphatics could therefore contribute to hypovolemia and hypotension associated with sepsis.


Assuntos
Endotoxemia/fisiopatologia , Lipopolissacarídeos/química , Vasos Linfáticos/fisiopatologia , Animais , Pressão Sanguínea , Corantes Fluorescentes/farmacologia , Homeostase , Masculino , Microcirculação , Proteínas/química , Ratos , Ratos Wistar , Sepse/fisiopatologia , Baço/metabolismo , Baço/fisiologia , Fatores de Tempo
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