ESTROGEN-RECEPTOR-ALPHA IS ESSENTIAL FOR INDUCTION OF OXYTOCIN RECEPTOR BY ESTROGEN

THE induction of oxytocin receptor (OTR) synthesis in the periphery an d in the brain by estrogen is critical for reproductive success. Oxyto cin receptors are involved in the control of parturition, milk ejectio n, and sexual and maternal behaviors. The discovery of a second estrog en receptor (ER beta) in the brain and the failure of in vitro transcr iption studies using OTR promoter constructs to replicate the in vivo transcriptional regulation have raised questions regarding the molecul ar mechanisms involved in the regulation of the OTR gene by estrogen. Using mice genetically deficient in estrogen receptor alpha (ER alpha) , we demonstrate that ER alpha is not necessary for basal OTR synthesi s, but is absolutely necessary for the induction of OTR binding in the brain by estrogen. (C) 1998 Rapid Science Ltd.