Figure 4. Total perikaryal ribosome content does not change in pharmacological models of epileptogenesis.

A–D, Mice were treated as in Fig. 3. A-C, Representative images of ribosome (NeuroTrace® 500/525 Green Fluorescent Nissl)- or DNA (Hoechst 33258) or the mossy fiber marker ZNT3 or the reactive astrocyte marker GFAP staining in the dorsal hippocampus of control or Pilo-SE mice (6 weeks post SE). A, Note apparent loss of Nissl stained cells in the DG hilus of Pilo-SE animals. Reduced Nissl staining in the CA region was also observed (Supplementary Fig. S1A). B-C, In the DG of control animals, ZNT3 staining is limited to the DG hilus/CA3 region (hil). In Pilo-SE mice, ZNT3 signal appears in the DG granule cell layer (gcl, arrowheads) and molecular layer (mcl, arrows) indicating mossy fiber sprouting (MFS). Presence of hypertrophic astrocytes with increased GFAP staining indicates reactive astrogliosis. These changes confirm post-SE neurodegeneration and hippocampal remodeling. D, In the granule cell layer of the DG, where perikarya of granule neurons are located, DNA-normalized ribosome content (i.e. fluorescence intensity ratio of NeuroTrace Green to Hoechst) was unaffected in Pilo-SE animals. E-F, Mice (C57Bl6 males) were treated with 10 sub-seizures doses of PTZ (35 mg/kg) or vehicle (control, ctrl) every other day; fully kindled animals that displayed tonic-clonic seizures (at least stage 4) after each of the last 5 injections of PTZ were used for evaluation of ribosome content. No significant changes in DNA-normalized content of ribosomes were observed in the granule cell layer of the DG or stratum pyramidale of the CA1 region of PTZ kindled mice; representative images of ribosomal staining in the dorsal hippocampus of PTZ-kindled mice are shown in Fig. S1. Data represent averages ± SEM, u-test comparisons are to respective control groups; ns, p>0.05; *, p<0.05.