PATIENTS WITH PREMENSTRUAL-SYNDROME HAVE A DIFFERENT SENSITIVITY TO ANEUROACTIVE STEROID DURING THE MENSTRUAL-CYCLE COMPARED TO CONTROL SUBJECTS

We have evaluated the functional sensitivity to a neuroactive steroid in 12 women with and 12 women without premenstrual syndrome (PMS) at t wo stages of the menstrual cycle, by comparing the effects of three in creasing doses of intravenous pregnanolone (3 alpha-hydroxy-5 beta-pre gnan-20-one) on saccadic eye velocity (SEV) and self-rated sedation, C ontrol subjects in the follicular and luteal phase showed a significan t reduction in SEV after pregnanolone injections compared to vehicle, In PMS patients, pregnanolone injections induced a significant dose-re lated decrease in SEV compared to vehicle only in the follicular phase , not in the luteal phase, After pregnanolone injections, sedation sco res increased significantly from vehicle among control subjects in the luteal phase but not among PMS patients in either cycle phase, High-s everity PMS patients responded with less decrease in SEV and less incr ease in sedation scores following pregnanolone injections compared to low-severity patients, Control subjects increased their SEV response t o pregnanolone in the luteal phase compared to the follicular phase, w hereas PMS patients did not, These findings are compatible with a decr eased GABA(A)-receptor sensitivity in brain areas controlling saccadic eye movements among PMS patients in the late luteal phase.