ESTROGEN RAPIDLY INDUCES THE PHOSPHORYLATION OF THE CAMP RESPONSE ELEMENT-BINDING PROTEIN IN RAT-BRAIN

Estrogen treatment of ovariectomized rats rapidly increases immunoreac tivity for the phosphorylated form of the cAMP response element bindin g protein (CREB) in neurons of the preoptic area and the bed nucleus o f the stria terminalis. These effects were detected within 15 min afte r estrogen exposure. Since the antisera used for these studies detect CREB phosphorylation at ser(133), which is important for transcription al activation, these data provide a possible explanation for estrogen' s effects on neuronal genes lacking estrogen response elements (EREs) but which contain cAMP response elements (CREs). These data also provi de evidence for non-genomic effects of steroid hormones involving prot ein kinase associated signal transduction pathways traditionally assoc iated with effects initiated at the cell membrane.