tailieunhanh - Báo cáo y học: " Real time analysis of b2-adrenoceptor-mediated signaling kinetics in Human Primary Airway Smooth Muscle Cells reveals both ligand and dose dependent differences"

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:" Real time analysis of b2-adrenoceptor-mediated signaling kinetics in Human Primary Airway Smooth Muscle Cells reveals both ligand and dose dependent differences. | Billington and Hall Respiratory Research 2011 12 89 http content 12 1 89 RESPIRATORY RESEARCH RESEARCH Open Access Real time analysis of p2-adrenoceptor-mediated signaling kinetics in Human Primary Airway Smooth Muscle Cells reveals both ligand and dose dependent differences Charlotte K Billington and Ian P Hall Abstract Background p2-adrenoceptor agonists elicit bronchodilator responses by binding to p2-adrenoceptors on airway smooth muscle ASM . In vivo the time between drug administration and clinically relevant bronchodilation varies significantly depending on the agonist used. Our aim was to utilise a fluorescent cyclic AMP reporter probe to study the temporal profile of p2-adrenoceptor-mediated signaling induced by isoproterenol and a range of clinically relevant agonists in human primary ASM hASM cells by using a modified Epac protein fused to CFP and a variant of YFP. Methods Cells were imaged in real time using a spinning disk confocal system which allowed rapid and direct quantification of emission ratio imaging following direct addition of p2-adrenoceptor agonists isoproterenol salbutamol salmeterol indacaterol and formoterol into the extracellular buffer. For pharmacological comparison a radiolabeling assay for whole cell cyclic AMP formation was used. Results Temporal analysis revealed that in hASM cells the p2-adrenoceptor agonists studied did not vary significantly in the onset of initiation. However once a response was initiated significant differences were observed in the rate of this response with indacaterol and isoproterenol inducing a significantly faster response than salmeterol. Contrary to expectation reducing the concentration of isoproterenol resulted in a significantly faster initiation of response. Conclusions We conclude that confocal imaging of the Epac-based probe is a powerful tool to explore p2-adrenoceptor signaling in primary cells. The ability to analyse the kinetics of clinically used p2-adrenoceptor .