Estrogen and the Aging Primate Brain

项目活动包括最近发表的一项研究，在该研究中，我们评估了四种激素治疗（HT）方案的认知效果，这些方案旨在模仿临床上用于女性的治疗方法（Baxter et al., 2013）。虽然我们早期的研究表明，每月急性雌激素注射有利于老年去卵巢猴子的前额皮质调节的工作记忆能力，但在临床研究中，雌性激素治疗往往不能改善认知功能。然而，这种差异是否反映了激素疗法的配方和时间上的差异，还没有得到系统的检验。值得注意的是，在我们的实验中检查的四种激素治疗中，没有一种对认知产生任何有益的影响，尽管记录了血清激素水平的疗效。与这些发现一致的是，与我们之前在提供循环雌激素的动物大脑中的结果相反，所有的HT方案都没有对猴子前额皮质的树突棘密度产生任何可检测到的影响（Ohm et al., 2013）。该项目的继续工作是测试卵巢激素下降后是否存在保护认知功能的机会之窗，以及手术绝经和激素治疗对脑形态计量学影响的各种相关问题。

Project activities include a recently published study in which we evaluated, in aged surgically menopausal rhesus monkeys, the cognitive effects of four hormone therapy (HT) regimens designed to mimic treatments used clinically in women (Baxter et al., 2013). Whereas our earlier work had demonstrated that monthly acute estrogen injection benefits working memory capacities mediated by the prefrontal cortex in aged ovariectormized monkeys, HT in women has often failed to improve cognitive function in clinical studies. The possibility that this discrepancy reflects differences in the formulation and timing of HT regimens, however, has not been tested systematically. Notably, none of the four hormone treatments examined in our experiments produced any beneficial effects on cognition, despite documented efficacy measured by serum hormone levels. Consistent with these findings, and in contrast to our previous results in brains from animals provided cyclic estrogen administration, none of the HT regimens tested had any detectable effect on dendritic spine density in the monkey prefrontal cortex (Ohm et al., 2013). Continuing work on this project is testing whether there is a window of opportunity for protecting cognitive function after ovarian hormone decline, together with a variety of related questions concerning the brain morphometric influence of surgical menopause and hormone therapy.