RESUMO
Administering recombinant interleukin-1 beta (IL-1 beta) intratracheally caused lung neutrophil accumulation and lung injury in hamsters. The percentage of leukocytes that were neutrophils increased progressively in lavages from lungs of hamsters given 25, 50, or 100 ng IL-1 beta intratracheally 2 h before. Lung injury, reflected by increased lung lavage protein concentrations and lung lavage hemoglobin concentrations, increased 2 h after administering 100 ng IL-1 beta. Lung injury, reflected by lung wet weight/body weight ratios, followed similar patterns, with significant increases occurring 2 h after insufflating 50 or 100 ng IL-1. Our results indicate that increased concentrations of IL-1 beta in lung airways can cause neutrophil recruitment and lung injury in hamsters. This mechanism may contribute to the development of lung neutrophil accumulation and lung injury that characterizes ARDS patients who have increased airway levels of IL-1 beta.
Assuntos
Interleucina-1/farmacologia , Neutrófilos/efeitos dos fármacos , Doença Aguda , Animais , Líquido da Lavagem Broncoalveolar/química , Líquido da Lavagem Broncoalveolar/citologia , Movimento Celular/efeitos dos fármacos , Cricetinae , Hemoglobinas/análise , Interleucina-1/administração & dosagem , Intubação Intratraqueal , Pneumopatias/induzido quimicamente , Pneumopatias/patologia , Masculino , Mesocricetus , Neutrófilos/fisiologia , Proteínas/análiseRESUMO
Characterization of the thrombolytic agent fibrolase was accomplished employing specific proteolytic and thrombolytic assays. This paper describes a method to measure enzyme proteolytic activity using the oxidized beta-chain of insulin as a substrate. Advantages of this method include a short incubation time for substrate cleavage followed by an isocratic HPLC method with a retention time of approx. 5 min. Proteolytic activity can be rapidly and easily quantitated with this procedure. An azocasein assay was also used to quantitate proteolytic activity. This method was optimized with respect to substrate concentration and incubation time allowing for the rapid quantitation of fibrolase activity. A thrombolytic assay is described which employs fibrin plate clearance and has the advantage of rapid and accurate quantitation compared with previously described methods. It also allows for the standardization of fibrolase in plasmin-equivalent units.
