In this study we evaluated oxidative stress (lipid peroxidation and protein oxidation) and thiol redox state [TRS: glutathione (GSH), glutathione disulfide (GSSG), cysteine (CSH), protein (P) thiols (PSH) and protein and non-protein (NP) mixed/symmetric disulfides (PSSR, NPSSR, NPSSC, PSSP)] in hippocampus after pentylenetetrazol (PTZ) administration at convulsive and subconvulsive dose. The significant decrease in PSH, CSH and NPSSC, as well as the increase in PSSP, NPSSR, lipid peroxidation and protein oxidation levels after PTZ-induced seizure indicate increased oxidative damage in hippocampus, although the levels of GSH and GSSG do not change significantly.