Clarithromycin On Cardiopulmonary Bypass Lung Injury In Animal Experiments And Related Basic Research

一, Experimental study on inductive effects of clarithromycin on human neutrophil apoptosis and its function in vitroBackground: Neutrophil plays a crucial role in inflammation response. Apoptotic senescent neutrophil are recognized and phagocytosed by macrophages. This neutrophil removal mechanism is important in control and resolution of inflammation. It has been reported that many macrolides antibiotics may affect functions of neutrophil and induce its apoptosis. Clarithromycin is a kind of new 14-membered ring macrolides antibiotic with long half life in tissue. This study investigated the inductive effects of clarithromycin on human neutrophil apoptosis and its function in vitro.Methods: The neutrophils were separated using discontinuous Percoll gradients. The cells were cultured in RPMI1640 at 37℃ in CO~2 incubator for 48 hours with or without clarithromycin. Neutrophil survival was determined by typan blue dye exclusion method. Apoptotic neutrophils were detected with flow cytometry and in situ end-labelling technique. Immune histochemistry was used to examine the expression of protein of Fas and bcl-2 which interrelated with neutrophil apoptosis. The activity of lactate dehydrogenase, myeloperoxidase and reactive oxygen products in the supernatant were determined by assay kits.Result: Clarithromycin significantly shortened neutrophil survival in a dose-dependent fashion. The survival-shortening effect of clarithromycin reached a maximum at 10 μg/ml and above: survival rates at 24h were 80.2 ± 3.1% for the control and 66.5 ± 2.2%, 63.5 ± 3.1% and 63.8 + 3.8% at 5, 10 and 20μg of...