Figure 5.

The P2X7R protein is upregulated in nerve terminals of the hippocampus of drug-refractory MTLE-HS human patients. Panel (A) shows that using our methodology nerve terminals isolated from the hippocampus of MTLE-HS patients exhibit a higher density of the synaptic vesicle marker, synaptophysin (~34 kDa), compared to the astrocytic cell marker, GFAP, whilst the opposite was observed in total hippocampal lysates. In panel (B) are shown representative Western blots of the P2X7R immunoreactivity in total lysates and nerve terminals isolated from the human hippocampus of control individuals and MTLE-HS patients; gels were loaded with 100 μg of protein. Two protein species were recognized by the P2X7R antibody from Alomone (#APR-004, Jerusalem, Israel) corresponding to the naturally occurring 67 kDa receptor isoform and to a higher molecular mass (~85 kDa) P2X7R isotype; the latter is highly enriched in nerve terminals of the hippocampus of MTLE-HS patients compared to non-epileptic controls. Please note that the two bands corresponding to the P2X7R protein disappeared after pre-adsorption of the primary antibody with a control antigen peptide equivalent to the amino-acid residues 576–595 of the intracellular C-terminus of the P2X7R (negative control); β-Actin (38–41 kDa) was used as a reference protein. Panel (C) shows computed data obtained from immunoblot experiments; data are expressed as mean ± SD; each individual sample was processed in duplicate; at least three individuals from each group (control and MTLE-HS) were analyzed.