FOS and status epilepticus: Furthermore, after an acute epileptogenic insult, Fos immediate early genes induction occurred in almost all the hippocampal PV-expressing interneurons up to 24 h after status epilepticus in Proechimys, contrasting to the lower proportion of the double labeled PV-Fos cells found in Wistar rats, thus suggesting differential mechanisms of GABAergic response between the two animals species (Fabene et al., 2004).