Abstract
The potent estrogen 17β-estradiol (E(2)) has long been known to regulate the hippocampus and hippocampal-dependent memories in females, and research from the past decade has begun to shed light on the molecular mechanisms through which E(2) mediates memory formation in females. Although E(2) can also regulate hippocampal function in males, relatively little is known about how E(2) influences memory formation in males, or whether sex differences in underlying mechanisms exist. This review, based on a talk given in April 2017 at the American University symposium entitled, "Sex Differences: From Neuroscience to the Clinic and Beyond", first provides an overview of the molecular mechanisms in the dorsal hippocampus through which E(2) enhances memory consolidation in ovariectomized female mice. Next, newer research is described demonstrating key roles for the prefrontal cortex and de novo hippocampal E(2) synthesis to the memory-enhancing effects of E(2) in females. The review then discusses the effects of de novo and exogenous E(2) on hippocampal memory consolidation in both sexes, and putative sex differences in the underlying molecular mechanisms through which E(2) enhances memory formation. The review concludes by discussing the importance and implications of sex differences in the molecular mechanisms underlying E(2)-induced memory consolidation for human health.