In recent years, there has been a growing appreciation that 17β-estradiol (E2) can rapidly modulate learning and memory processes by binding to membrane estrogen receptors and cause the activation of a number of signaling cascades within the central nervous system. In this study, we sought to investigate the effects of post-training administration of E2 (100 ng/g, 1 μg/g, 10 μg/g) and involvement of the estrogen receptors (ERs) using selective ER agonists on the consolidation of object recognition (OR) and object placement memory (OP) in adult male zebrafish. The general activation of ERs with the highest E2 dose improved consolidation of memory in both learning tasks within 1.45 h of administration. Activation of classical ERs (ERα and ERβ) improved consolidation of OR memory, but had no effect on fish performance in OP task. On the other hand, activation of G protein-coupled ER1 impaired and enhanced consolidation of OR and OP memories, respectively. Memory improvement in both tasks was accompanied by a marked up-regulation in the expression of genes encoding ionotropic and metabotropic glutamate receptors in a task-dependent manner. In contrast, the down-regulation in the expression of certain ionotropic glutamate receptors was observed in fish with impaired OR memory. Moreover, our study also revealed an increase in the transcript abundance of genes associated with synaptic protein synthesis (brain-derived neurotrophic factor, synaptophysin, and the mechanistic target of rapamycin). These results suggest that E2 may affect consolidation of memory in zebrafish likely through rapid changes in synaptic morphology and function.

中文翻译：

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雌二醇及其受体激动剂对成年雄性斑马鱼物体识别和物体放置的快速影响。

近年来，人们越来越认识到17β-雌二醇（E2）可以通过与膜雌激素受体结合来快速调节学习和记忆过程，并引起中枢神经系统内许多信号级联的激活。在这项研究中，我们试图研究使用选择性ER激动剂对E2（100 ng / g，1μg/ g，10μg/ g）的训练后给药和雌激素受体（ER）的参与对固结的影响。成年雄性斑马鱼的物体识别（OR）和物体放置记忆（OP）。具有最高E2剂量的ER的一般激活改善了在1.45 h的两个学习任务中记忆的巩固。经典ER（ERα和ERβ）的激活改善了OR记忆的巩固，但对OP任务中的鱼类生长没有影响。另一方面，G蛋白偶联的ER1的激活分别削弱和增强OR和OP记忆的整合。两项任务的记忆力改善均伴随着以任务依赖方式编码离子型和代谢型谷氨酸受体的基因表达显着上调。相反，在OR记忆受损的鱼类中观察到某些离子型谷氨酸受体表达的下调。此外，我们的研究还揭示了与突触蛋白合成相关的基因（脑源性神经营养因子，突触素和雷帕霉素的作用靶点）的转录本丰富度增加。这些结果表明，E2可能通过突触形态和功能的快速变化来影响斑马鱼的记忆巩固。