In postmortem brain specimens, there were no transcription differences between MDD men and controls, and the levels of 5-HT1D receptors and the transcription factors NUDR and REST, which regulate 5-HT activity, in 5-HT-containing neurons in the ventral raphe nuclei were found to be higher in MDD females.452 5-HT receptors and regulators were shown to exhibit sex-specific alterations in expression at the protein level, and postmortem investigations have largely focused on female subjects. This evidence concerns the gene REST and major depressive disorder.