MURINE STEROID SULFATASE GENE-EXPRESSION IN THE BRAIN DURING POSTNATAL-DEVELOPMENT AND ADULTHOOD

The microsomal enzyme steroid sulfatase (STS, E.C.3.1.6.2) plays a cen tral function in the neurosteroid mode of action, since it is responsi ble for the switch between the sulfated and the free forms of steroids which have opposite effects. In this study, using an enzyme linked im munosorbent assay (ELISA) for the STS, we have investigated the brain expression of STS in mice during development. We confirm that STS is p resent in the brain as previously shown by the measurement of the enzy matic activity. At birth, the STS level is clearly higher than in adul ts. We observed differences between physiological stages in females br ain. The STS level is the same in pregnant and non-pregnant females, w hereas STS concentration dramatically increased after delivery and dur ing lactation.