Quantitation of eosinophil and neutrophil infiltration into rat lung by specific assays for eosinophil peroxidase and myeloperoxidase. Application in a Brown Norway rat model of allergic pulmonary inflammation

摘要: Conditions for measuring selectively eosinophil peroxidase (EPO) and the neutrophil myeloperoxidase (MPO) in inflamed rat lung were determined. EPO could be specifically measured with o-phenylene diamine as chromogen at pH 8.0 presence of 3 mM bromide MPO tetramethylbenzidine 5.0 absence but inhibitor, resorcinol. Aeroallergen challenge sensitized Brown Norway rats ovalbumin, not saline, resulted a pronounced eosinophilic inflammation some focal hemorrhages an increase wet weights. Quantitation accumulation required lyophilization samples, hypotonic wash to remove contaminating hemoglobin, which interfered assay, followed by extraction detergent cetyltrimethylammonium chloride. Based on activities standardization enzyme activity purified eosinophils neutrophils, total number neutrophils lungs was calculated 24 h (n = 19), 48 9) 72 4) after challenge, 56 +/- 6.4 x 10(6), 119 28 10(6) 108 33 eosinophils, respectively, 94 6.8 49 32 5.5 respectively. We conclude that, assay conditions outlined here, can used quantitate tissue infiltration even mixed inflammatory reactions.