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1.
Intensive Care Med ; 46(11): 1977-1986, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-33104824

RESUMO

The aim of this Intensive Care Medicine Rapid Practice Guideline (ICM-RPG) is to formulate an evidence-based guidance for the use of neuromuscular blocking agents (NMBA) in adults with acute respiratory distress syndrome (ARDS). The panel comprised 20 international clinical experts from 12 countries, and 2 patient representatives. We adhered to the methodology for trustworthy clinical practice guidelines and followed a strict conflict of interest policy. We convened panelists through teleconferences and web-based discussions. Guideline experts from the guidelines in intensive care, development, and evaluation Group provided methodological support. Two content experts provided input and shared their expertise with the panel but did not participate in drafting the final recommendations. We followed the Grading of Recommendations Assessment, Development, and Evaluation approach to assess the certainty of evidence and grade recommendations and suggestions. We used the evidence to decision framework to generate recommendations. The panel provided input on guideline implementation and monitoring, and suggested future research priorities. The overall certainty in the evidence was low. The ICM-RPG panel issued one recommendation and two suggestions regarding the use of NMBAs in adults with ARDS. Current evidence does not support the early routine use of an NMBA infusion in adults with ARDS of any severity. It favours avoiding a continuous infusion of NMBA for patients who are ventilated using a lighter sedation strategy. However, for patients who require deep sedation to facilitate lung protective ventilation or prone positioning, and require neuromuscular blockade, an infusion of an NMBA for 48 h is a reasonable option.


Assuntos
Bloqueio Neuromuscular , Bloqueadores Neuromusculares , Síndrome do Desconforto Respiratório , Adulto , Cuidados Críticos , Humanos , Respiração Artificial , Síndrome do Desconforto Respiratório/tratamento farmacológico
2.
Acta Anaesthesiol Scand ; 62(10): 1443-1451, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-29926908

RESUMO

BACKGROUND: Oxygen is liberally administered in intensive care units (ICUs). Nevertheless, ICU doctors' preferences for supplementing oxygen are inadequately described. The aim was to identify ICU doctors' preferences for arterial oxygenation levels in mechanically ventilated adult ICU patients. METHODS: In April to August 2016, an online multiple-choice 17-part-questionnaire was distributed to 1080 ICU doctors in seven Northern European countries. Repeated reminder e-mails were sent. The study ended in October 2016. RESULTS: The response rate was 63%. When evaluating oxygenation 52% of respondents rated arterial oxygen tension (PaO2 ) the most important parameter; 24% a combination of PaO2 and arterial oxygen saturation (SaO2 ); and 23% preferred SaO2 . Increasing, decreasing or not changing a default fraction of inspired oxygen of 0.50 showed preferences for a PaO2 around 8 kPa in patients with chronic obstructive pulmonary disease, a PaO2 around 10 kPa in patients with healthy lungs, acute respiratory distress syndrome or sepsis, and a PaO2 around 12 kPa in patients with cardiac or cerebral ischaemia. Eighty per cent would accept a PaO2 of 8 kPa or lower and 77% would accept a PaO2 of 12 kPa or higher in a clinical trial of oxygenation targets. CONCLUSION: Intensive care unit doctors preferred PaO2 to SaO2 in monitoring oxygen treatment when peripheral oxygen saturation was not included in the question. The identification of PaO2 as the preferred target and the thorough clarification of preferences are important when ascertaining optimal oxygenation targets. In particular when designing future clinical trials of higher vs lower oxygenation targets in ICU patients.


Assuntos
Unidades de Terapia Intensiva , Oxigênio/sangue , Respiração Artificial , Humanos , Oxigênio/toxicidade , Médicos , Doença Pulmonar Obstrutiva Crônica/metabolismo , Síndrome do Desconforto Respiratório/metabolismo
4.
Acta Anaesthesiol Scand ; 62(4): 420-450, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29479665

RESUMO

BACKGROUND: Adult critically ill patients often suffer from acute circulatory failure and those with low cardiac output may be treated with inotropic agents. The aim of this Scandinavian Society of Anaesthesiology and Intensive Care Medicine guideline was to present patient-important treatment recommendations on this topic. METHODS: This guideline was developed according to GRADE. We assessed the following subpopulations of patients with shock: (1) shock in general, (2) septic shock, (3) cardiogenic shock, (4) hypovolemic shock, (5) shock after cardiac surgery, and (6) other types of shock, including vasodilatory shock. We assessed patient-important outcome measures, including mortality and serious adverse reactions. RESULTS: For all patients, we suggest against the routine use of any inotropic agent, including dobutamine, as compared to placebo/no treatment (very low quality of evidence). For patients with shock in general, and in those with septic and other types of shock, we suggest using dobutamine rather than levosimendan or epinephrine (very low quality of evidence). For patients with cardiogenic shock and in those with shock after cardiac surgery, we suggest using dobutamine rather than milrinone (very low quality of evidence). For the other clinical questions, we refrained from giving any recommendations or suggestions. CONCLUSIONS: We suggest against the routine use of any inotropic agent in adult patients with shock. If used, we suggest using dobutamine rather than other inotropic agents for the majority of patients, however, the quality of evidence was very low, implying high uncertainty on the balance between the benefits and harms of inotropic agents.


Assuntos
Anestesiologia , Cardiotônicos/uso terapêutico , Guias de Prática Clínica como Assunto , Choque/tratamento farmacológico , Doença Aguda , Cuidados Críticos , Dobutamina/uso terapêutico , Humanos , Sociedades Médicas
6.
Acta Anaesthesiol Scand ; 60(6): 697-709, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26988416

RESUMO

BACKGROUND: The objective of the Scandinavian Society of Anaesthesiology and Intensive Care Medicine (SSAI) task force on fluid and drug therapy in adults with acute respiratory distress syndrome (ARDS) was to provide clinically relevant, evidence-based treatment recommendations according to standards for trustworthy guidelines. METHODS: The guideline was developed according to standards for trustworthy guidelines, including a systematic review of the literature and use of the GRADE methodology for assessment of the quality of evidence and for moving from evidence to recommendations. RESULTS: A total of seven ARDS interventions were assessed. We suggest fluid restriction in patients with ARDS (weak recommendation, moderate quality evidence). Also, we suggest early use of neuromuscular blocking agents (NMBAs) in patients with severe ARDS (weak recommendation, moderate quality evidence). We recommend against the routine use of other drugs, including corticosteroids, beta2 agonists, statins, and inhaled nitric oxide (iNO) or prostanoids in adults with ARDS (strong recommendations: low- to high-quality evidence). These recommendations do not preclude the use of any drug or combination of drugs targeting underlying or co-existing disorders. CONCLUSION: This guideline emphasizes the paucity of evidence of benefit - and potential for harm - of common interventions in adults with ARDS and highlights the need for prudence when considering use of non-licensed interventions in this patient population.


Assuntos
Cuidados Críticos , Síndrome do Desconforto Respiratório/tratamento farmacológico , Corticosteroides/uso terapêutico , Adulto , Hidratação , Humanos , Bloqueadores Neuromusculares/uso terapêutico
7.
Acta anaesthesiol. scand ; 59(3)Mar. 2015. tab
Artigo em Inglês | BIGG - guias GRADE | ID: biblio-965786

RESUMO

BACKGROUND: The objective of the Scandinavian Society of Anaesthesiology and Intensive Care Medicine (SSAI) task force on mechanical ventilation in adults with the acute respiratory distress syndrome (ARDS) is to formulate treatment recommendations based on available evidence from systematic reviews and randomised trials. METHODS: This guideline was developed according to standards for trustworthy guidelines through a systematic review of the literature and the use of the Grading of Recommendations Assessment, Development and Evaluation system for assessment of the quality of evidence and for moving from evidence to recommendations in a systematic and transparent process. RESULTS: We found evidence of moderately high quality to support a strong recommendation for pressure limitation and small tidal volumes in patients with ARDS. Also, we suggest positive end-expiratory pressure (PEEP) > 5 cm H2O in moderate to severe ARDS and prone ventilation 16/24 h for the first week in moderate to severe ARDS (weak recommendation, low quality evidence). Volume controlled ventilation or pressure control may be equally beneficial or harmful and partial modes of ventilatory support may be used if clinically feasible (weak recommendation, very low quality evidence). We suggest utilising recruitment manoeuvres as a rescue measure in catastrophic hypoxaemia only (weak recommendation, low quality evidence). Based on high-quality evidence, we strongly recommend not to use high-frequency oscillatory ventilation. We could find no relevant data from randomised trials to guide decisions on choice of FiO2 or utilisation of non-invasive ventilation. CONCLUSION: We strongly recommend pressure- and volume limitation and suggest using higher PEEP and prone ventilation in patients with severe respiratory failure.(AU)


Assuntos
Humanos , Adulto , Respiração Artificial/métodos , Síndrome do Desconforto Respiratório do Recém-Nascido/reabilitação , Ventilação de Alta Frequência/efeitos adversos
8.
Acta Anaesthesiol Scand ; 59(3): 286-97, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25524779

RESUMO

BACKGROUND: The objective of the Scandinavian Society of Anaesthesiology and Intensive Care Medicine (SSAI) task force on mechanical ventilation in adults with the acute respiratory distress syndrome (ARDS) is to formulate treatment recommendations based on available evidence from systematic reviews and randomised trials. METHODS: This guideline was developed according to standards for trustworthy guidelines through a systematic review of the literature and the use of the Grading of Recommendations Assessment, Development and Evaluation system for assessment of the quality of evidence and for moving from evidence to recommendations in a systematic and transparent process. RESULTS: We found evidence of moderately high quality to support a strong recommendation for pressure limitation and small tidal volumes in patients with ARDS. Also, we suggest positive end-expiratory pressure (PEEP) > 5 cm H2O in moderate to severe ARDS and prone ventilation 16/24 h for the first week in moderate to severe ARDS (weak recommendation, low quality evidence). Volume controlled ventilation or pressure control may be equally beneficial or harmful and partial modes of ventilatory support may be used if clinically feasible (weak recommendation, very low quality evidence). We suggest utilising recruitment manoeuvres as a rescue measure in catastrophic hypoxaemia only (weak recommendation, low quality evidence). Based on high-quality evidence, we strongly recommend not to use high-frequency oscillatory ventilation. We could find no relevant data from randomised trials to guide decisions on choice of FiO2 or utilisation of non-invasive ventilation. CONCLUSION: We strongly recommend pressure- and volume limitation and suggest using higher PEEP and prone ventilation in patients with severe respiratory failure.


Assuntos
Respiração Artificial/métodos , Síndrome do Desconforto Respiratório/terapia , Adulto , Humanos , Países Escandinavos e Nórdicos , Sociedades Médicas
9.
Acta Anaesthesiol Scand ; 55(7): 835-41, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21615346

RESUMO

BACKGROUND: Percutaneous dilatational tracheotomy (PT) is safe and cost effective, and has become a routine method in intensive care units (ICU), but safety concerns persist for obese patients and for patients with a high risk of bleeding. In this prospective study of 1000 PTs, we have investigated whether such patient characteristics were associated with an increased procedural risk. METHODS: We prospectively recorded all PTs performed in our ICU from 2001 to 2009. Data on blood transfusion were entered from a central database. The association of risk factors with bleeding and other complications was analysed with logistic regression. RESULTS: The total number of PTs and surgical tracheotomies was 1.454. The median number of days on a ventilator until PT was 6 in 2001, decreasing to 3 in 2009. A procedure-related complication was reported in 17.5%. There was no PT-related mortality. The rate of potentially life-threatening complications was 1.2%. Three patients developed pneumothorax and one of these had circulatory arrest and was successfully resuscitated. Three hundred and twelve patients had one or more units of blood transfused, but only 19 (1.9%) were PT related. Increased INR was the most important risk factor for bleeding [odds ratio (OR) 2.99], followed by low platelets (OR 1.99). The rate of complications in patients with high body mass index was not increased. CONCLUSION: PT is a safe procedure that can be performed with a low complication rate in patients with increased risk of bleeding as well as in obese patients.


Assuntos
Cuidados Críticos , Hemorragia/complicações , Obesidade/complicações , Traqueotomia/métodos , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Índice de Massa Corporal , Criança , Pré-Escolar , Estudos de Coortes , Dilatação , Feminino , Hemorragia/epidemiologia , Hemorragia/terapia , Hemostasia , Humanos , Lactente , Recém-Nascido , Unidades de Terapia Intensiva , Masculino , Pessoa de Meia-Idade , Razão de Chances , Pneumotórax/etiologia , Estudos Prospectivos , Risco , Fatores de Risco , Traqueotomia/mortalidade , Adulto Jovem
10.
Parasitol Res ; 109(3): 581-9, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21347520

RESUMO

The peritoneal cavity (PNC) and intestine of northern fur seal (Callorhinus ursinus) pups and California sea lion (Zalophus californianus) pups that died in late July and early August, 2003, on San Miguel Island, California, were examined for hookworms. Prevalence and morphometric studies were done with the hookworms in addition to molecular characterization. Based on this and previous molecular studies, hookworms from fur seals are designated as Uncinaria lucasi and the species from sea lions as Uncinaria species A. Adult hookworms were found in the PNC of 35 of 57 (61.4%) fur seal pups and of 13 of 104 (12.5%) sea lion pups. The number of hookworms located in the PNC ranged from 1 to 33 (median = 3) for the infected fur seal pups and 1 to 16 (median = 2) for the infected sea lion pups. In addition to the PNC, intestines of 43 fur seal and 32 sea lion pups were examined. All of these pups were positive for adult hookworms. The worms were counted from all but one of the sea lion pups. Numbers of these parasites in the intestine varied from 3 to 2,344 (median = 931) for the fur seal pups and 39 to 2,766 (median = 643) for the sea lion pups. Sea lion pups with peritoneal infections had higher intensity infections in the intestines than did pups without peritoneal infections, lending some support for the hypothesis that peritoneal infections result from high-intensity infections of adult worms. There was no difference in intestinal infection intensities between fur seal pups with and without peritoneal infections. Female adult hookworms in the intestines of both host species were significantly larger than males, and sea lion hookworms were larger than those in fur seals. Worms in the intestine also were larger than worms found in the PNC. Gene sequencing and (RFLP) analysis of (PCR) amplified (ITS) ribosomal DNA were used to diagnose the species of 172 hookworms recovered from the PNC and intestine of 18 C. ursinus and seven Z. californianus hosts. These molecular data revealed that U. lucasi (hookworm of C. ursinus) and Uncinaria species A (of Z. californianus) infrequently mature in the intestine of the opposite host species in California rookeries. However, there is no support from molecular data for the hypothesis that cross-infection with "the wrong" Uncinaria species is a contributing factor in these cases of host peritonitis. The major significance of this research is the unusual finding of adult hookworms in the PNC of so many dead pups. No obvious explanation for this occurrence could be determined. Further research, like in the present study, should help understand and monitor the apparent ever changing role of hookworm disease in the health of northern fur seal and California sea lion pups on SMI.


Assuntos
Ancylostomatoidea/classificação , Ancylostomatoidea/isolamento & purificação , Otárias/parasitologia , Infecções por Uncinaria/veterinária , Enteropatias Parasitárias/veterinária , Doenças Peritoneais/veterinária , Leões-Marinhos/parasitologia , Ancylostomatoidea/genética , Animais , DNA de Helmintos/química , DNA de Helmintos/genética , DNA Espaçador Ribossômico/química , DNA Espaçador Ribossômico/genética , Feminino , Infecções por Uncinaria/parasitologia , Enteropatias Parasitárias/parasitologia , Masculino , Carga Parasitária , Doenças Peritoneais/parasitologia , Análise de Sequência de DNA
12.
Acta Anaesthesiol Scand ; 54(4): 479-84, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19930244

RESUMO

BACKGROUND: A high birth rate during the first two decades following World War II has increased the proportion of elderly people in present-day society and, consequently, the demand for health-care services. The impact on intensive care services may become dramatic because the age distribution of critically ill patients is skewed towards the elderly. We have used registry data and population statistics to forecast the demand for intensive care services in Norway up until the year 2025. METHODS: Data collected by the Norwegian intensive care registry (NIR), showing the age distribution in Norwegian intensive care units (ICU) during the years 2006 and 2007, were used with three different Norwegian prognostic models of population growth for the years 2008-2025 to compute the expected increase in intensive care unit bed-days (ICU bed-days). RESULTS: The elderly were overrepresented in Norwegian ICUs in 2006-2007, with patients from 60 to 79 years of age occupying 44% of ICU bed-days. Population growth from 2008 to 2025 was estimated to be from 11.1 to 26.4%, depending on the model used. Growth will be much larger in the age group 60-79 years. Other factors kept unchanged, this will result in an increase in the need for intensive care (ICU bed-days) of between 26.1 and 36.9%. CONCLUSION: The demand for intensive care beds will increase markedly in Norwegian hospitals in the near future. This will have serious implications for the planning of infrastructure, education of health care personnel, as well as financing of our health care system.


Assuntos
Idoso/estatística & dados numéricos , Cuidados Críticos/estatística & dados numéricos , Pessoa de Meia-Idade , Fatores Etários , Coeficiente de Natalidade , Feminino , Previsões , Planejamento em Saúde , Humanos , Tempo de Internação , Expectativa de Vida , Masculino , Noruega/epidemiologia , Dinâmica Populacional
13.
Acta Anaesthesiol Scand ; 51(2): 137-42, 2007 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-17181536

RESUMO

BACKGROUND: Therapeutic hypothermia has been shown to increase survival after out-of-hospital cardiac arrest (OHCA). The trials documenting such benefit excluded patients with cardiogenic shock and only a few patients were treated with percutaneous coronary intervention prior to admission to an intensive care unit (ICU). We use therapeutic hypothermia whenever cardiac arrest patients do not wake up immediately after return of spontaneous circulation. METHODS: This paper reports the outcome of 50 OHCA patients with ventricular fibrillation admitted to a tertiary referral hospital for immediate coronary angiography and percutaneous coronary intervention when indicated. Patients were treated with intra-aortic balloon counterpulsation (IABP) (23 of 50 patients) if indicated. All patients who were still comatose were treated with therapeutic hypothermia at 32-34 degrees C for 24 h before rewarming. The end-points were survival and cerebral performance category (CPC: 1, best; 5, dead) after 6 months. RESULTS: Forty-one patients (82%) survived until 6 months. Thirty-four patients (68%) were in CPC 1 or 2, and seven (14%) were in CPC 3. Of the 23 patients treated with IABP, 14 (61%) survived with CPC 1 or 2. In patients not treated with IABP, 20 patients (74%) survived with CPC 1 or 2. Forty patients (80%) developed myocardial infarction. Percutaneous coronary intervention was performed in 36 patients (72%). CONCLUSION: In OHCA survivors who reached our hospital, the survival rate was high and the neurological outcome acceptable. Our results indicate that the use of therapeutic hypothermia is justified even in haemodynamically unstable patients and those treated with percutaneous coronary intervention.


Assuntos
Parada Cardíaca/terapia , Hipotermia Induzida/métodos , Idoso , Coma/terapia , Angiografia Coronária , Feminino , Seguimentos , Humanos , Hipotermia Induzida/mortalidade , Balão Intra-Aórtico/métodos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Choque Cardiogênico/terapia , Taxa de Sobrevida , Resultado do Tratamento , Fibrilação Ventricular/terapia
14.
Biometrics ; 62(2): 372-8, 2006 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-16918901

RESUMO

Mark-recapture models applied to double-observer distance sampling data neglect the information on relative detectability of objects contained in the distribution of observed distances. A difference between the observed distribution and that predicted by the mark-recapture model is symptomatic of a failure of the assumption of zero correlation between detection probabilities implicit in the mark-recapture model. We develop a mark-recapture-based model that uses the observed distribution to relax this assumption to zero correlation at only one distance. We demonstrate its usefulness in coping with unmodeled heterogeneity using data from an aerial survey of crabeater seals in the Antarctic.


Assuntos
Biometria , Animais , Animais Selvagens , Regiões Antárticas , Coleta de Dados , Funções Verossimilhança , Modelos Estatísticos , Densidade Demográfica , Estudos de Amostragem , Focas Verdadeiras
16.
Parasitol Res ; 96(2): 127-32, 2005 May.
Artigo em Inglês | MEDLINE | ID: mdl-15824900

RESUMO

Intestines of California sea lion (Zalophus californianus) pups (n= 204), born in 2002 on San Miguel Island, California, were examined for hookworms (Uncinaria spp.) as part of a seasonal mortality study from June through December 2002 and January 2003. The investigation was planned to coincide with most of the previously established hookworm infection period of the pups. Prevalence of hookworms in dead pups was 100% for each month of the study. The geometric mean intensity of infections per month was: 94.03 (n=30) for June, 629.09 (n=50) for July, 319.90 (n=31) for August, 159.90 (n=30) for October, 109.03 (n=30) for November, 37.84 (n=24) for December 2002 and 11.05 (n=9) for January 2003. In addition to the temporal pattern, the infection intensity was higher for pups in good condition and for male pups. An inter-year comparison of hookworm counts from dead pups collected in July of 1996, 2000, and 2002 also demonstrated higher intensity in pups in better condition but sex-differences in intensity were inconsistent across years. The inter-year comparison also demonstrated higher intensities in dead pups collected from portions of the rookery with sandy substrate versus rocky substrate. No annual differences in intensity were found after adjusting for substrate and condition.


Assuntos
Ancylostomatoidea/isolamento & purificação , Infecções por Uncinaria/veterinária , Leões-Marinhos/parasitologia , Estações do Ano , Animais , California/epidemiologia , Feminino , Infecções por Uncinaria/epidemiologia , Infecções por Uncinaria/parasitologia , Intestinos/parasitologia , Masculino , Contagem de Ovos de Parasitas , Prevalência , Leões-Marinhos/crescimento & desenvolvimento
17.
Acta Anaesthesiol Scand ; 45(10): 1196-203, 2001 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11736669

RESUMO

Drug induced anaphylaxis is frequently attributed to the use of muscle relaxants during anaesthesia. Recently The Norwegian Medicines Agency recommended that rocuronium bromide (Esmeron) be withdrawn from routine practice due to frequent reports of anaphylaxis. Over a period of two and a half years approximately 150,000 patients received rocuronium as part of their anaesthesia. In this period the Norwegian drug authorities received 29 reports of anaphylaxis or anaphylactoid reactions in patients treated with rocuronium. This is in stark contrast to the situation in other Nordic countries where a total of only seven cases of anaphylaxis in approximately 800,000 patients treated with rocuronium had been recorded by December 2000. This situation highlights the many potential problems of the surveillance of adverse drug reactions: reporting bias may lead to an over-estimate of the risk of one drug compared to another, and the possibility of under-reporting of adverse events (due to a weak reporting culture) further limit the validity of such comparisons. The surveillance of adverse drug reactions also represents a statistical challenge. While adverse event reports may help us to estimate the anaphylaxis rate we need to appreciate the uncertainty of such estimates. Adverse reactions are rare, random, and mostly independent events, resulting from the successive exposure of patients to a low risk intervention. The frequency distribution of adverse events will therefore conform to that of a Poisson process. The resulting Poisson distribution may inform us about the variability of adverse event data. An understanding of these methodological problems and statistical challenges will allow anaesthesiologists to make informed decisions concerning the use of muscle relaxants and other drugs associated with severe adverse reactions.


Assuntos
Anafilaxia/induzido quimicamente , Androstanóis/efeitos adversos , Anestesia , Fármacos Neuromusculares não Despolarizantes/efeitos adversos , Sistemas de Notificação de Reações Adversas a Medicamentos , Anafilaxia/epidemiologia , Análise por Conglomerados , Humanos , Incidência , Modelos Estatísticos , Noruega/epidemiologia , Distribuição de Poisson , Risco , Rocurônio , Estatística como Assunto
18.
Am J Physiol Cell Physiol ; 279(3): C648-57, 2000 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-10942715

RESUMO

Two pools of phosphate-activated glutaminase (PAG) were separated from pig and rat renal mitochondria. The partition of enzyme activity corresponded with that of the immunoreactivity and also with the postembedding immunogold labeling of PAG, which was associated partly with the inner membrane and partly with the matrix. The outer membrane was not labeled. PAG in intact mitochondria showed enzymatic characteristics that were similar to that of the membrane fraction and also mimicked that of the polymerized form of purified pig renal PAG. PAG in the soluble fraction showed properties similar to that of the monomeric form of purified enzyme. It is indicated that the pool of PAG localized inside the inner mitochondrial membrane is dormant due to the presence of high concentrations of the inhibitor glutamate. Thus the enzymatically active PAG is assumed to be localized on the outer face of the inner mitochondrial membrane. The activity of this pool of PAG appears to be regulated by compounds in the cytosol, of which glutamate may be most important.


Assuntos
Glutaminase/metabolismo , Rim/enzimologia , Partículas Submitocôndricas/enzimologia , Animais , Ativação Enzimática/fisiologia , Ácido Glutâmico/metabolismo , Ácido Glutâmico/farmacologia , Glutaminase/antagonistas & inibidores , Concentração de Íons de Hidrogênio , Immunoblotting , Imuno-Histoquímica , Membranas Intracelulares/metabolismo , Rim/ultraestrutura , Microscopia Eletrônica , Mitocôndrias/metabolismo , Mitocôndrias/fisiologia , Mitocôndrias/ultraestrutura , Ratos , Ratos Wistar , Solubilidade , Partículas Submitocôndricas/ultraestrutura , Suínos , Distribuição Tecidual
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