fig3

Figure 3. Potential markers for microglial activation in young and old rats with or without surgery. (a) The corrected optical density as marker for microglia activation; (b) The percentage of activated microglia (with an activation stage ≥ 3) based on visual characterization. (c) The cell body to cell size ratio (%) as marker for microglia activation. YC: young control; YS: young surgery; OC: old control; OS: old surgery. ^**P < 0.01 and ^***P < 0.001 compared to young rats. ⁺P < 0.05 and ⁺⁺P < 0.01 compared to age matched controls