近日，美国加州大学尔湾分校Gary Lynch、Christine M. Gall等研究人员合作发现，青春期前的雌性啮齿动物具有增强的海马长期电位（LTP）和学习能力。该研究于2022年1月27日在线发表于国际一流学术期刊《自然—神经科学》。

研究人员发现，在啮齿动物中，青春期前的雌性迅速编码空间信息并表达低阈值长期电位（LTP），而年龄匹配的雄性则没有。雌性青春期低阈值LTP的丧失与三个相互关联的变化有关：抑制性突触上含α5亚单位的GABA_AR密度增加，用于诱导LTP的突发反应的分流更大，以及NMDAR介导的突触反应的减少。α5-GABA_AR的负向异构调节因子在成年雌性中比在青少年雌性中更大程度地增加了突发反应，并明显地增强了成年的LTP和空间记忆。雄性青春期功能获得的原因并不涉及这些机制。总而言之，青春期对两种性别的可塑性有相反的后果，尽管是通过不同的途径。

据悉，多项研究表明，成年雄性啮齿动物在空间问题上的表现比雌性好，而且海马CA3-CA1突触的LTP阈值较低。

附：英文原文

Title: Prepubescent female rodents have enhanced hippocampal LTP and learning relative to males, reversing in adulthood as inhibition increases

Author: Le, Aliza A., Lauterborn, Julie C., Jia, Yousheng, Wang, Weisheng, Cox, Conor D., Gall, Christine M., Lynch, Gary

Issue&Volume: 2022-01-27

Abstract: Multiple studies indicate that adult male rodents perform better than females on spatial problems and have a lower threshold for long-term potentiation (LTP) of hippocampal CA3-to-CA1 synapses. We report here that, in rodents, prepubescent females rapidly encode spatial information and express low-threshold LTP, whereas age-matched males do not. The loss of low-threshold LTP across female puberty was associated with three inter-related changes: increased densities of α5 subunit-containing GABAARs at inhibitory synapses, greater shunting of burst responses used to induce LTP and a reduction of NMDAR-mediated synaptic responses. A negative allosteric modulator of α5-GABAARs increased burst responses to a greater degree in adult than in juvenile females and markedly enhanced both LTP and spatial memory in adults. The reasons for the gain of functions with male puberty do not involve these mechanisms. In all, puberty has opposite consequences for plasticity in the two sexes, albeit through different routes.

DOI: 10.1038/s41593-021-01001-5

Source: https://www.nature.com/articles/s41593-021-01001-5