Figure 1: Effects of corticosterone on the chemotaxis of rat peritoneal macrophages. The upper and lower chambers were separated by a 5 μm pore-sized (arrow) polycarbonate membrane filter (polyvinylpyrrolidone-free). FMLP (10 nM) was added into the lower wells to induce cell migration. The filled chamber was incubated at 37°C for 3 h and then the cells that had not migrated into the lower chamber were scraped off. The filter was fixed with 4% paraformaldehyde for 20 min and the cells were stained with hematoxylin-eosin. The migrated cells (arrowhead) were counted under microscopy (×400). (a) Rat peritoneal macrophages were treated with vehicle diluent (ethanol) as control. Macrophages were treated with 30 nM, 150 nM, and 3 μM corticosterone, respectively. (b) The results were representative of five independent experiments performed on triplicate samples. * versus the control group.