FOS and epilepsy: To further investigate whether DFP exposure induces overexpression of other IEGs, we analyzed, by qRT-PCR, the expression in the brain of fosab, atf3, junBa, npas4a, and npas4b, the zebrafish orthologues of C-FOS, JUNB, ATF3, and NPAS4, respectively, four genes that are expressed at high levels in the very first hours that follow epileptic seizures in pharmacological models of epilepsy in rats25.