Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 31
Filtrar
1.
BMC Nephrol ; 25(1): 247, 2024 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-39085790

RESUMO

BACKGROUND: Rhabdomyolysis describes a syndrome characterized by muscle necrosis and the subsequent release of creatine kinase and myoglobin into the circulation. Myoglobin elimination with extracorporeal hemoadsorption has been shown to effectively remove myoglobin from the circulation. Our aim was to provide best practice consensus statements developed by the Hemoadsorption in Rhabdomyolysis Task Force (HRTF) regarding the use of hemadsorption for myoglobin elimination. METHODS: A systematic literature search was performed until 11th of January 2023, after which the Rhabdomyolysis RTF was assembled comprising international experts from 6 European countries. Online conferences were held between 18th April - 4th September 2023, during which 37 consensus questions were formulated and using the Delphi process, HRTF members voted online on an anonymised platform. In cases of 75 to 90% agreement a second round of voting was performed. RESULTS: Using the Delphi process on the 37 questions, strong consensus (> 90% agreement) was achieved in 12, consensus (75 to 90% agreement) in 10, majority (50 to 74%) agreement in 13 and no consensus (< 50% agreement) in 2 cases. The HRTF formulated the following recommendations: (1) Myoglobin contributes to the development of acute kidney injury; (2) Patients with myoglobin levels of > 10,000 ng/ml should be considered for extracorporeal myoglobin removal by hemoadsorption; (3) Hemoadsorption should ideally be started within 24 h of admission; (4) If myoglobin cannot be measured then hemoadsorption may be indicated based on clinical picture and creatinine kinase levels; (5) Cartridges should be replaced every 8-12 h until myoglobin levels < 10,000 ng/ml; (6) In patients with acute kidney injury, hemoadsorption can be discontinued before dialysis is terminated and should be maintained until the myoglobin concentration values are consistently < 5000 ng/ml. CONCLUSIONS: The current consensus of the HRTF support that adjuvant hemoadsorption therapy in severe rhabdomyolysis is both feasible and safe and may be an effective method to reduce elevated circulating levels of myoglobin.


Assuntos
Mioglobina , Rabdomiólise , Humanos , Rabdomiólise/terapia , Mioglobina/sangue , Hemadsorção , Técnica Delphi , Consenso
2.
J Clin Med ; 11(22)2022 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-36431292

RESUMO

Background: Extracorporeal hemadsorption eliminates proinflammatory mediators in critically ill patients with hyperinflammation. The use of a pumpless extracorporeal hemadsorption technique allows its early usage prior to organ failure and the need for an additional medical device. In our animal model, we investigated the feasibility of pumpless extracorporeal hemadsorption over a wide range of mean arterial pressures (MAP). Methods: An arteriovenous shunt between the femoral artery and femoral vein was established in eight pigs. The hemadsorption devices were inserted into the shunt circulation; four pigs received CytoSorb® and four Oxiris® hemadsorbers. Extracorporeal blood flow was measured in a range between mean arterial pressures of 45-85 mmHg. Mean arterial pressures were preset using intravenous infusions of noradrenaline, urapidil, or increased sedatives. Results: Extracorporeal blood flows remained well above the minimum flows recommended by the manufacturers throughout all MAP steps for both devices. Linear regression resulted in CytoSorb® blood flow [mL/min] = 4.226 × MAP [mmHg] - 3.496 (R-square 0.8133) and Oxiris® blood flow [mL/min] = 3.267 × MAP [mmHg] + 57.63 (R-square 0.8708), respectively. Conclusion: Arteriovenous pumpless extracorporeal hemadsorption resulted in sufficient blood flows through both the CytoSorb® and Oxiris® devices over a wide range of mean arterial blood pressures and is likely an intriguing therapeutic option in the early phase of septic shock or hyperinflammatory syndromes.

4.
Leukemia ; 35(10): 2917-2923, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34385593

RESUMO

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) causes COVID-19 (coronavirus disease 2019), which is associated with high morbidity and mortality, especially in elder patients. Acute respiratory distress syndrome (ARDS) is a life-threatening complication of COVID-19 and has been linked with severe hyperinflammation. Dexamethasone has emerged as standard of care for COVID-19 associated respiratory failure. In a non-randomized prospective phase II multi-center study, we asked whether targeted inhibition of Janus kinase-mediated cytokine signaling using ruxolitinib is feasible and efficacious in SARS-CoV-2- induced ARDS with hyperinflammation. Sixteen SARS-CoV-2 infected patients requiring invasive mechanical ventilation for ARDS were treated with ruxolitinib in addition to standard treatment. Ruxolitinib treatment was well tolerated and 13 patients survived at least the first 28 days on treatment, which was the primary endpoint of the trial. Immediate start of ruxolitinib after deterioration was associated with improved outcome, as was a lymphocyte-to-neutrophils ratio above 0.07. Together, treatment with the janus-kinase inhibitor ruxolitinib is feasible and might be efficacious in COVID-19 induced ARDS patients requiring invasive mechanical ventilation. The trial has been registered under EudraCT-No.: 2020-001732-10 and NCT04359290.


Assuntos
COVID-19/complicações , Inibidores de Janus Quinases/uso terapêutico , Janus Quinases/antagonistas & inibidores , Pirazóis/uso terapêutico , Síndrome do Desconforto Respiratório/tratamento farmacológico , SARS-CoV-2/isolamento & purificação , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Nitrilas , Prognóstico , Pirimidinas , Síndrome do Desconforto Respiratório/epidemiologia , Síndrome do Desconforto Respiratório/virologia , Taxa de Sobrevida
5.
Blood Purif ; 50(6): 968-970, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33503608

RESUMO

In recent years, extracorporeal hemadsorption (HA) techniques capable of adsorbing pro- and anti-inflammatory cytokines are increasingly used in various clinical situations. The therapeutic benefit of cytokine elimination likely depends on timing. Although treatment seems to be most effective when started within the first 24 h, therapy is often delayed as it must be combined with another extracorporeal circuit. Thus, using a pumpless extracorporeal HA technique might be a valuable option in order to expedite the commencement of cytokine elimination in critically ill patients.


Assuntos
Citocinas/isolamento & purificação , Hemoperfusão/instrumentação , Animais , Circulação Sanguínea , Estado Terminal , Citocinas/sangue , Desenho de Equipamento , Hemoperfusão/métodos , Humanos , Estudo de Prova de Conceito , Suínos
6.
Acta Anaesthesiol Scand ; 65(5): 629-632, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33296498

RESUMO

BACKGROUND: Changes in pulmonary hemodynamics and ventilation/perfusion were proposed as hallmarks of Coronavirus disease 2019 (COVID-19)-induced acute respiratory distress syndrome (ARDS). Inhaled nitric oxide (iNO) may overcome these issues and improve arterial oxygenation. METHODS: We retrospectively analyzed arterial oxygenation and pulmonary vasoreactivity in seven COVID-19 ARDS patients receiving 20 ppm iNO for 15-30 minutes. RESULTS: The inhalation of NO significantly improved oxygenation. All patients with severe ARDS had higher partial pressures of oxygen and reduced pulmonary vascular resistance. Significant changes in pulmonary shunting were not observed. CONCLUSION: Overall, iNO could provide immediate help and delay respiratory deterioration in COVID-19-induced moderate to severe ARDS.


Assuntos
Tratamento Farmacológico da COVID-19 , Óxido Nítrico/administração & dosagem , Síndrome do Desconforto Respiratório/tratamento farmacológico , SARS-CoV-2 , Administração por Inalação , COVID-19/complicações , Hemodinâmica , Humanos , Síndrome do Desconforto Respiratório/fisiopatologia , Estudos Retrospectivos
7.
Anaesthesist ; 70(5): 376-382, 2021 05.
Artigo em Alemão | MEDLINE | ID: mdl-33258990

RESUMO

BACKGROUND: Survival rates after an out-of-hospital cardiac arrest (OHCA) remain low. Extracorporeal cardiopulmonary resuscitation (eCPR) has been introduced as an attempt to increase survival in selected patients and observational studies have shown promising results. Nevertheless, inclusion criteria and timing of eCPR remain undefined. OBJECTIVE: The current study analyzed a load and go strategy with respect to the golden hour of eCPR as a cut-off time for survival and favorable neurological outcome. MATERIAL AND METHODS: This retrospective cohort study included 32 patients who underwent eCPR treatment due to an OHCA between January 2017 and September 2019. Routinely taken patient demographic data (age, BMI, sex) were analyzed. The main focus was set on processing times in the preclinical and clinical setting. Time intervals including OHCA until ambulance arrival, time on scene, transportation times and door to eCPR were extracted from emergency medical service (EMS) and resuscitation protocols. Low-flow times, survival and neurological outcome were analyzed. RESULTS: The use of eCPR in OHCA was associated with survival to hospital discharge in 28% and a good neurological outcome in 19% of the cases. Both groups (survivor and nonsurvivor) did not differ in patient demographics except for age. Survivors were significantly younger (47 (30-60) vs. 59 (50-68) years, p = 0.035). Processing times as well as low-flow times were not significantly different (OHCA-eCPR survivor 64 (50-87) vs. non-survivor 74 (51-85) min; p-value 0.64); however, median low-flow times were outside the golden hour of eCPR (69 (52-86)). CONCLUSION: Despite low-flow times of more than 60 min, eCPR was associated with survival in 28% after OHCA. Hence, exceeding the golden hour of eCPR cannot act as a definitive exclusion criterion for eCPR.


Assuntos
Reanimação Cardiopulmonar , Serviços Médicos de Emergência , Oxigenação por Membrana Extracorpórea , Parada Cardíaca Extra-Hospitalar , Humanos , Parada Cardíaca Extra-Hospitalar/terapia , Estudos Retrospectivos
8.
Front Immunol ; 11: 580547, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33363532

RESUMO

Respiratory syncytial virus (RSV) is the leading cause of acute lower respiratory tract infections in young children. Currently, there is no RSV vaccine or universally accessible antiviral treatment available. Addressing the urgent need for new antiviral agents, we have investigated the capacity of a non-coding single-stranded oligonucleotide (ssON) to inhibit RSV infection. By utilizing a GFP-expressing RSV, we demonstrate that the ssON significantly reduced the proportion of RSV infected A549 cells (lung epithelial cells). Furthermore, we show that ssON's antiviral activity was length dependent and that both RNA and DNA of this class of oligonucleotides have antiviral activity. We reveal that ssON inhibited RSV infection by competing with the virus for binding to the cellular receptor nucleolin in vitro. Additionally, using a recombinant RSV that expresses luciferase we show that ssON effectively blocked RSV infection in mice. Treatment with ssON in vivo resulted in the upregulation of RSV-induced interferon stimulated genes (ISGs) such as Stat1, Stat2, Cxcl10, and Ccl2. This study highlights the possibility of using oligonucleotides as therapeutic agents against RSV infection. We demonstrate that the mechanism of action of ssON is the inhibition of viral entry in vitro, likely through the binding of the receptor, nucleolin and that ssON treatment against RSV infection in vivo additionally results in the upregulation of ISGs.


Assuntos
DNA de Cadeia Simples/genética , Oligonucleotídeos/genética , Mucosa Respiratória/metabolismo , Infecções por Vírus Respiratório Sincicial/terapia , Vírus Sinciciais Respiratórios/fisiologia , Células A549 , Animais , Quimiocina CCL2/genética , Quimiocina CXCL10/genética , Feminino , Humanos , Interferons/genética , Interferons/metabolismo , Camundongos , Fosfoproteínas/genética , Fosfoproteínas/metabolismo , Ligação Proteica , Proteínas de Ligação a RNA/genética , Proteínas de Ligação a RNA/metabolismo , Mucosa Respiratória/patologia , Fator de Transcrição STAT1/genética , Fator de Transcrição STAT2/genética , Internalização do Vírus , Nucleolina
11.
Front Med (Lausanne) ; 7: 599533, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33392222

RESUMO

Background: Proportions of patients dying from the coronavirus disease-19 (COVID-19) vary between different countries. We report the characteristics; clinical course and outcome of patients requiring intensive care due to COVID-19 induced acute respiratory distress syndrome (ARDS). Methods: This is a retrospective, observational multicentre study in five German secondary or tertiary care hospitals. All patients consecutively admitted to the intensive care unit (ICU) in any of the participating hospitals between March 12 and May 4, 2020 with a COVID-19 induced ARDS were included. Results: A total of 106 ICU patients were treated for COVID-19 induced ARDS, whereas severe ARDS was present in the majority of cases. Survival of ICU treatment was 65.0%. Median duration of ICU treatment was 11 days; median duration of mechanical ventilation was 9 days. The majority of ICU treated patients (75.5%) did not receive any antiviral or anti-inflammatory therapies. Venovenous (vv) ECMO was utilized in 16.3%. ICU triage with population-level decision making was not necessary at any time. Univariate analysis associated older age, diabetes mellitus or a higher SOFA score on admission with non-survival during ICU stay. Conclusions: A high level of care adhering to standard ARDS treatments lead to a good outcome in critically ill COVID-19 patients.

12.
Perfusion ; 34(8): 714-716, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31146629

RESUMO

Targeted temperature management and extracorporeal life support, particularly extracorporeal membrane oxygenation in patients undergoing cardiopulmonary resuscitation, represent outcome-enhancing strategies for patients following in- and out-of-hospital cardiac arrest. Although targeted temperature management with hypothermia between 32°C and 34°C and extracorporeal cardiopulmonary resuscitation bear separate potentials to improve outcome after out-of-hospital cardiac arrest, each is associated with bleeding risk and risk of infection. Whether the combination imposes excessive risk on patients is, however, unknown.


Assuntos
Oxigenação por Membrana Extracorpórea/métodos , Hipotermia Induzida/métodos , Parada Cardíaca Extra-Hospitalar/terapia , Europa (Continente) , Oxigenação por Membrana Extracorpórea/efeitos adversos , Feminino , Hemorragia/etiologia , Humanos , Hipotermia Induzida/efeitos adversos , Infecções/etiologia , Masculino , Inquéritos e Questionários
14.
Indian J Crit Care Med ; 21(5): 274-280, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28584430

RESUMO

AIMS: Sedation, as it is often required in critical care, is associated with immobilization, prolonged ventilation, and increased morbidity. Most sedation protocols are based on benzodiazepines. The presented study analyzes the benefit of benzodiazepine-free sedation. METHODS: In 2008, 134 patients were treated according to a protocol using benzodiazepine and propofol (Group 1). In 2009, we introduced a new sedation strategy based on sufentanil, nonsteroidal anti-inflammatory drugs, neuroleptics, and antidepressants, which was applied in 140 consecutive patients (Group 2). Depth of sedation, duration of mechanical ventilation, duration of Intensive Care Unit, and hospital stay were analyzed. RESULTS: Group 1 had both a longer duration of deep sedation (18.7 ± 2.5 days vs. 12.6 ± 1.85 days, P = 0.031) and a longer duration of controlled ventilation (311, 35 ± 32.69 vs. 143, 96 ± 20.76 h, P < 0.0001) than Group 2. Ventilator days were more frequent in Group 1 (653, 66 ± 98.37 h vs. 478, 89 ± 68.92 h, P = 0.128). CONCLUSIONS: The benzodiazepine-free sedation protocol has been shown to significantly reduce depth of sedation and controlled ventilation. Additional evidence is needed to ascertain reduction of ventilator days which would not only be of benefit for the patient but also for the hospital Management.

15.
J Thorac Dis ; 9(3): 818-830, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28449491

RESUMO

BACKGROUND: Little is known about the characteristics and real world life circumstances of ARDS (acute respiratory distress syndrome) patient populations. This knowledge is essential for transferring evidence-based therapy into routine healthcare. The aim of this study was to report socio-demographic and clinical characteristics in an unselected population of ARDS patients and to compare these results to findings from other large ARDS cohorts. METHODS: A German based cross-sectional observational study was carried out. A total of 700 ARDS patients were recruited in 59 study sites between September 2014 and January 2016. Socio-demographic, disease and care related variables were recorded. Additionally, characteristics of other large ARDS cohorts identified by a systematic literature search were extracted into evidence tables. RESULTS: Median age of ARDS patients was 58 years, 69% were male. Sixty percent had no employment, predominantly due to retirement. Seventy-one percent lived with a partner. The main cause of ARDS was a pulmonary 'direct' origin (79%). The distribution of severity was as follows: mild (14%), moderate (48%), severe (38%). Overall ICU mortality was calculated to be 34%. The observed prevalence of critical events (hypoxemia, hypoglycemia, re-intubation) was 47%. Supportive measures during ICU-treatment were applied to 60% of the patients. Other ARDS cohorts revealed a high heterogeneity in reported concomitant diseases, but sepsis and pneumonia were most frequently reported. Mean age ranged from 54 to 71 years and most patients were male. Other socio-demographic factors have been almost neglected. CONCLUSIONS: The proportion of patients suffering of mild ARDS was lower compared to the only study identified, which also applied the Berlin definition. The frequency of critical events during ICU treatment was high and the implementation of evidence-based therapy (prone positioning, neuro-muscular blockers) was limited. More evidence on socio-demographic characteristics and further studies applying the current diagnostic criteria are desirable.

16.
Artigo em Alemão | MEDLINE | ID: mdl-27631445

RESUMO

Cardiovascular complications, particularly perioperative myocardial infarction (PMI), are major contributors to mortaliyt after noncardiac surgery. PMI often occurs unnoticed without symptoms or ECG changes. Despite ist silent presentation, PMI is associated with increased mortality. The combination of high associated mortality and diagnostic challenges mandates increased awareness of PMI. Perioperative myocardial infarction may result from plaque rupture (PMI type I) or be caused by a myocardial supply-demand imbalance of oxygen without plaque rupture (PMI type II). Most PMIs occur within the first 3 days after surgery, highlighting the need for clinical monitoring in order to allow fast diagnosis and initiation of appropriate therapy. Measurement of cardiac troponin and 12-lead ECG are the diagnostic cornerstone. Therapy of PMI represents a challenge for physicians and requires a collaboration of surgeons, anesthesiologists and cardiologists.


Assuntos
Morte Súbita Cardíaca/etiologia , Infarto do Miocárdio/etiologia , Infarto do Miocárdio/terapia , Assistência Perioperatória/métodos , Complicações Pós-Operatórias/terapia , Procedimentos Cirúrgicos Operatórios/efeitos adversos , Alemanha , Humanos , Monitorização Intraoperatória/métodos , Infarto do Miocárdio/diagnóstico , Equipe de Assistência ao Paciente/organização & administração , Assistência Perioperatória/efeitos adversos , Complicações Pós-Operatórias/diagnóstico , Complicações Pós-Operatórias/etiologia
17.
Thorac Cardiovasc Surg Rep ; 4(1): 14-7, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26693120

RESUMO

Background Matthys catheters (Matthys drainage A Set, Bösch Feinmechanik und Medizintechnik GmbH, Gottenheim, Germany) are thin catheters with an external diameter of 2.7 mm, which are often used in internal medicine to drain pleural effusions. After puncturing the pleural cavity with a hollow needle the Matthys catheter is advanced through it without resistance. Once the three-way tap on the catheter has been opened, the pleural effusion should flow out. Case Description In our case, the positioning of the Matthys catheter was thought to be completely straightforward but an X-ray check nonetheless revealed malposition. The catheter had been advanced surprisingly over the left upper lobe bronchus across the carina into the right upper lobe bronchus. No thoracic bleeding occurred. Conclusion Although the Matthys catheter was placed endobronchially, we removed it without air leakage. Fortunately, no further problems occurred.

18.
J Mol Cell Cardiol ; 81: 71-80, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25655935

RESUMO

TASK-1 channels have emerged as promising drug targets against atrial fibrillation, the most common arrhythmia in the elderly. While TASK-3, the closest relative of TASK-1, was previously not described in cardiac tissue, we found a very prominent expression of TASK-3 in right human auricles. Immunocytochemistry experiments of human right auricular cardiomyocytes showed that TASK-3 is primarily localized at the plasma membrane. Single-channel recordings of right human auricles in the cell-attached mode, using divalent-cation-free solutions, revealed a TASK-1-like channel with a single-channel conductance of about 30pS. While homomeric TASK-3 channels were not found, we observed an intermediate single-channel conductance of about 55pS, possibly reflecting the heteromeric channel formed by TASK-1 and TASK-3. Subsequent experiments with TASK-1/TASK-3 tandem channels or with co-expressed TASK-1 and TASK-3 channels in HEK293 cells or Xenopus oocytes, supported that the 55pS channels observed in right auricles have electrophysiological characteristics of TASK-1/TASK-3 heteromers. In addition, co-expression experiments and single-channel recordings suggest that heteromeric TASK-1/TASK-3 channels have a predominant surface expression and a reduced affinity for TASK-1 blockers. In summary, the evidence for heteromeric TASK-1/TASK-3 channel complexes together with an altered pharmacologic response to TASK-1 blockers in vitro is likely to have further impact for studies isolating ITASK-1 from cardiomyocytes and for the development of drugs specifically targeting TASK-1 in atrial fibrillation treatment.


Assuntos
Fibrilação Atrial/metabolismo , Átrios do Coração/metabolismo , Miócitos Cardíacos/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Canais de Potássio de Domínios Poros em Tandem/metabolismo , Potenciais de Ação/efeitos dos fármacos , Potenciais de Ação/fisiologia , Animais , Fibrilação Atrial/patologia , Fibrilação Atrial/cirurgia , Benzamidas/farmacologia , Benzenoacetamidas/farmacologia , Membrana Celular/efeitos dos fármacos , Membrana Celular/metabolismo , Feminino , Regulação da Expressão Gênica , Células HEK293 , Átrios do Coração/citologia , Humanos , Miócitos Cardíacos/citologia , Miócitos Cardíacos/efeitos dos fármacos , Proteínas do Tecido Nervoso/antagonistas & inibidores , Proteínas do Tecido Nervoso/genética , Oócitos/citologia , Oócitos/efeitos dos fármacos , Oócitos/metabolismo , Técnicas de Patch-Clamp , Bloqueadores dos Canais de Potássio/farmacologia , Canais de Potássio de Domínios Poros em Tandem/antagonistas & inibidores , Canais de Potássio de Domínios Poros em Tandem/genética , Cultura Primária de Células , Multimerização Proteica , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Transdução de Sinais , Sulfonamidas/farmacologia , Xenopus laevis , ortoaminobenzoatos/farmacologia
19.
Pflugers Arch ; 467(5): 1081-90, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25511502

RESUMO

Atrial fibrillation and obstructive sleep apnea are responsible for significant morbidity and mortality in the industrialized world. There is a high medical need for novel drugs against both diseases, and here, Kv1.5 channels have emerged as promising drug targets. In humans, TASK-1 has an atrium-specific expression and TASK-1 is also abundantly expressed in the hypoglossal motor nucleus. We asked whether known Kv1.5 channel blockers, effective against atrial fibrillation and/or obstructive sleep apnea, modulate TASK-1 channels. Therefore, we tested Kv1.5 blockers with different chemical structures for their TASK-1 affinity, utilizing two-electrode voltage clamp (TEVC) recordings in Xenopus oocytes. Despite the low structural conservation of Kv1.5 and TASK-1 channels, we found all Kv1.5 blockers analyzed to be even more effective on TASK-1 than on Kv1.5. For instance, the half-maximal inhibitory concentration (IC50) values of AVE0118 and AVE1231 (A293) were 10- and 43-fold lower on TASK-1. Also for MSD-D, ICAGEN-4, S20951 (A1899), and S9947, the IC50 values were 1.4- to 70-fold lower than for Kv1.5. To describe this phenomenon on a molecular level, we used in silico models and identified unexpected structural similarities between the two drug binding sites. Kv1.5 blockers, like AVE0118 and AVE1231, which are promising drugs against atrial fibrillation or obstructive sleep apnea, are in fact potent TASK-1 blockers. Accordingly, block of TASK-1 channels by these compounds might contribute to the clinical effectiveness of these drugs. The higher affinity of these blockers for TASK-1 channels suggests that TASK-1 might be an unrecognized molecular target of Kv1.5 blockers effective in atrial fibrillation or obstructive sleep apnea.


Assuntos
Antiarrítmicos/farmacologia , Fibrilação Atrial/metabolismo , Canal de Potássio Kv1.5/antagonistas & inibidores , Proteínas do Tecido Nervoso/metabolismo , Canais de Potássio de Domínios Poros em Tandem/metabolismo , Apneia Obstrutiva do Sono/tratamento farmacológico , Animais , Fibrilação Atrial/tratamento farmacológico , Compostos de Bifenilo/farmacologia , Canal de Potássio Kv1.5/metabolismo , Bloqueadores dos Canais de Potássio/farmacologia , Apneia Obstrutiva do Sono/metabolismo , Xenopus laevis/metabolismo
20.
Pflugers Arch ; 467(5): 1055-67, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25404566

RESUMO

The current kinetics of two-pore domain potassium (K2P) channels resemble those of the steady-state K(+) currents being active during the plateau phase of cardiac action potentials. Recent studies support that K2P channels contribute to these cardiac currents and thereby influence action potential duration in the heart. Ten of the 15 K2P channels present in the human genome are sensitive to variations of the extracellular and/or intracellular pH value. This review focuses on a set of K2P channels which are inhibited by extracellular protons, including the subgroup of tandem of P domains in a weak inward-rectifying K(+) (TWIK)-related acid-sensitive potassium (TASK) and TWIK-related alkaline-activated K(+) (TALK) channels. The role of TWIK-1 in the heart is also discussed since, after successful expression, an extracellular pH dependence, similar to that of TASK-1, was described as a hallmark of TWIK-1. The expression profile in cardiac tissue of different species and the functional data in the heart are summarized. The distinct role of the different acid-sensitive K2P channels in cardiac electrophysiology, inherited forms of arrhythmias and pharmacology, and their role as drug targets is currently emerging and is the subject of this review.


Assuntos
Arritmias Cardíacas/metabolismo , Eletrofisiologia Cardíaca , Potenciais da Membrana/fisiologia , Canais de Potássio de Domínios Poros em Tandem/metabolismo , Potássio/metabolismo , Potenciais de Ação/fisiologia , Animais , Eletrofisiologia Cardíaca/métodos , Humanos
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA