Allopregnanolone and Dynamic GABA-A Receptor Plasticity in Selective Serotonin Reuptake Inhibitor Responsive Premenstrual Dysphoric Disorder

Premenstrual dysphoric disorder (PMDD) is a severe affective disorder impacting millions of women worldwide, thought to be due to altered sensitivity to hormone fluctuations across the menstrual cycle. Neuroactive steroid hormones (NAS) and the gamma-aminobutyric acid (GABA)-A receptor (GABAAR) are thought to play a role in PMDD. This research will assess the blood levels of GABAergic NAS, expression of associated enzymes, and expression of GABAAR subunits across the premenstrual (luteal) phase of the menstrual cycle in healthy controls and individuals with PMDD. Within the PMDD group, the investigators will assess how these measures are affected by a low-dose antidepressant medication versus placebo. The results will provide a comprehensive view of the changes in these systems across the menstrual cycle and will add to the investigator's understanding of the mechanisms that underlie PMDD, as well as therapeutic mechanisms of PMDD treatment.