Fig. 3
Hippocampal synaptic deficits following late prenatal immune activation. a Relative optical density (in arbitrary units (AU)) of synaptophysin immunoreactivity in the cornu ammonis (CA; including CA1–CA3 sub-regions) and dentate gyrus (DG) of pubescent, adult, and aged offspring born to poly(I:C)-exposed (POL) and control (CON) mothers. ANOVA revealed a significant main effect of age (CA: F (2,61) = 108.53, P < 0.001; DG: F (2,61) = 78.27, P < 0.001) and its interaction with prenatal treatment (CA: F (2,61) = 8.27, P < 0.001; DG: F (2,61) = 3.72, P < 0.05). + P < 0.001, reflecting significantly lower levels of synaptophysin immunoreactivity in pubescent CON and POL offspring relative to adult or aged CON and POL offspring; # P < 0.001, reflecting the significant difference between aged POL and aged CON offspring; § P < 0.01 and §§ P < 0.001, reflecting the significant difference between aged POL and adult CON or POL offspring, based on Fisher’s least significant (LSD) post hoc tests. N(pubescent CON) = 11, N(pubescent POL) = 10, N(adult CON) = 12, N(adult POL) = 10, N(aged CON) = 12, N(aged POL) = 12. b Representative hippocampal sections of aged CON and POL offspring stained with anti-synaptophysin antibody. Note the lack of immunoreactivity in the corpus callosum (cc), which served as normalizing background measurement. c Quantification of hippocampal synaptophysin protein levels in aged CON and POL offspring using Western blot analysis. *P < 0.05 (t (21) = 2.58), based on independent Student’s t test. N(aged CON) = 13, N(aged POL) = 10. d Representative Western blot samples for synaptophysin protein in the hippocampus of aged CON and POL offspring. β-actin is shown as loading control for comparison. e Expression of total BDNF, BDNF exon IV, and BDNF exon VI in the hippocampus of adult and aged CON and POL offspring. The bar plots show normalized mRNA expression levels as assessed using quantitative RT-PCR. *P < 0.05 and ***P < 0.001, based on post hoc analyses following the presence of a significant interaction between prenatal treatment and age (total BDNF: F (1,44) = 4.69, P < 0.05; BDNF exon VI: F (1,48) = 4.71, P < 0.05); + P < 0.001, reflecting the significant difference between adult and aged CON or POL offspring associated with the main effect of age (F (1,44) = 15.85, P < 0.001). N(adult CON) = 13, N(adult POL) = 12, N(aged CON) = 13, and N(aged POL) = 10. All values are means ± s.e.m.