Migrating activity and oxidative burst of Agtr1^–/– and Agtr1^+/+ macrophages. (a) Migrating activity of isolated peritoneal macrophages was determined by using chemotaxis chambers. In the left panel, Agtr1^–/– or Agtr1^+/+ macrophages were incubated with either vehicle (black bars) or 0.1 μg/ml MCP-1(white bars). In the right panel, Agtr1^+/+ macrophages were exposed to vehicle (white bar), 1 × 10^–6 M angiotensin II alone (gray bar), or 0.1 μg/ml MCP-1 and 1 × 10^–6 M angiotensin II (black bar). Migrated cells were counted and are shown as the number of migrated cells per field. *P < 0.05 for vehicle versus MCP-1. (b) Macrophages of the Agtr1^–/– (black bar) or the Agtr1^+/+ (white bar) genotype were examined for Fcγ receptor–mediated oxidative burst. Oxidative burst was detected as fluorescence emitted by macrophages and is indicated in arbitrary units. Ang II, angiotensin II; MCP-1, monocyte chemotactic protein-1.