Age is associated with increased macrophage infiltration and chemokine expression. There was a significant increase in the percentage of macrophages (A) in the brains of older rats (*
P < 0.05; Student’s t-test; n = 4); values are presented as means (±SEM). (B) A representative plot of the flow cytometry data. There was an age-related increase in IP-10 (C) and MCP-1 (D) mRNA expression in hippocampal tissue (*
P < 0.05; Student’s t-test; n = 6 to 15). For mRNA data, values are presented as means (±SEM) and expressed as a ratio to β-actin mRNA. IP-10, interferon gamma-induced protein 10; MCP-1, monocytes chemotactic protein 1; RQ, relative quantities.