Tuyển tập các báo cáo nghiên cứu về y học được đăng trên tạp chí y học 'Respiratory Research cung cấp cho các bạn kiến thức về ngành y đề tài: "Dissociation by steroids of eosinophilic inflammation from airway hyperresponsiveness in murine airways. | Respiratory Research BioMed Central Research Open Access Dissociation by steroids of eosinophilic inflammation from airway hyperresponsiveness in murine airways Mark A Birrell1 Cliff H Battram2 Paul Woodman3 Kerryn McCluskie1 and Maria G Belvisi 1 Address imperial College School of Medicine London UK 2Novartis Horsham East Sussex UK and 3Bayer Plc. Slough Berks. UK Email Maria G Belvisi - Corresponding author Published 21 March 2003 Received 25 January 2002 Accepted 21 November 2002 Respir Res 2003 4 3 This article is available from http content 4 l 3 2003 Kim et al licensee BioMed Central Ltd. This article is published in Open Access verbatim copying and redistribution of this article are permitted in all media for any non-commercial purpose provided this notice is preserved along with the article s original URL Abstract Background The link between eosinophils and the development of airway hyperresponsiveness AHR in asthma is still controversial. This question was assessed in a murine model of asthma in which we performed a dose ranging study to establish whether the dose of steroid needed to inhibit the eosinophil infiltration correlated with that needed to block AHR. Methods The sensitised BALB c mice were dosed with vehicle or dexamethasone mg kg 2 hours before and 6 hours after each challenge once daily for 6 days and 2 hours before AHR determination by whole-body plethysmography. At 30 minutes after the AHR to aerosolised methacholine the mice were lavaged and differential white cell counts were determined. Challenging with antigen caused a significant increase in eosinophils in the bronchoalveolar lavage BAL fluid and lung tissue and increased AHR. Results Dexamethasone reduced BAL and lung tissue eosinophilia ED50 values of and mg kg respectively whereas a higher dose was needed to block AHR ED50 of mg kg at 3 mg ml methacholine. Dissociation was observed between the dose of steroid needed to
