Fig. 4

Acute DFP intoxication increases expression of the microglial biomarker IBA1 in the hippocampus and cortex. Rats injected with DFP (9 mg/kg ip) or an equal volume (300 μl) of vehicle (VEH) were euthanized at 1, 2, 3, 7, 14, and 21 days post-exposure to collect the brains for IBA1 immunostaining. The area of IBA1 immunoreactivity per field (three fields per section in three sections per brain) was quantified in the cortex and hippocampus to assess microglial activation. a Representative photomicrographs of IBA1 immunoreactivity in the hippocampus and cortex of rats administered VEH or DFP at 1 and 7 days post-injection. Bar = 50 μm. b Dot plots of the log area of IBA1 immunofluorescence in the hippocampus and cortex. Each dot represents the data from an individual animal while the horizontal gray bars represent the geometric mean of the log area of IBA1 immunofluorescence for all animals at each time point. Note: VEH across all time points are shown as one group because there were no significant time-dependent differences between them. *Significantly different from VEH at p < .05; **p < .01; ***p < .001. c The geometric mean ratio (dot) and 95 % confidence interval (bar) of the area of IBA1 immunofluorescence in DFP-exposed rats relative to VEH controls. Confidence intervals not overlapping y = 1 (gray horizontal bar) indicate a significant difference between DFP and VEH conditions (p < .05)