ArticleFrontiers in neural circuits2013
Female hippocampal estrogens have a significant correlation with cyclic fluctuation of hippocampal spines.
Article in Frontiers in neural circuits, 2013. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 84 papers.
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Who cites it
84 citing papers in PubMed, 166 citations in OpenAlex.
- Article
- Consideration of sex as a biological variable over the history of the 5xFAD Alzheimer's Disease mouse model.Biology of sex differences · 2025Article
- The estrous cycle modulates hippocampal spine dynamics, dendritic processing, and spatial coding.Neuron · 2025Article
- Estrogenic regulation of hippocampal inhibitory system across lifespan.Journal of neuroendocrinology · 2025Review
- Neuroestrogens, the hippocampus, and female cognitive aging.Hormones and behavior · 2025Review
- Local synthesis and function of neuro-estrogen and neuro-androgen: impact on the hippocampus-related cognition and neuronal plasticity.Frontiers in cellular neuroscience · 2025Review
- Impacts of CACNB4 overexpression on dendritic spine density in both sexes and relevance to schizophrenia.Translational psychiatry · 2024Article
- Rapid and local neuroestrogen synthesis supports long-term potentiation of hippocampal Schaffer collaterals-cornu ammonis 1 synapse in ovariectomized mice.Journal of neuroendocrinology · 2024Article
- Contributions of site- and sex-specific LTPs to everyday memory.Philosophical transactions of the Royal Society of London. Series B, Biological sciences · 2024Review
- Sex- and cycle-dependent changes in spine density and size in hippocampal CA2 neurons.Scientific reports · 2024Article
- Sex differences in the context dependency of episodic memory.Frontiers in behavioral neuroscience · 2024Article
- Connecting the Dots: Potential Interactions Between Sex Hormones and the Circadian System During Memory Consolidation.Journal of biological rhythms · 2023Article
- Exploring the Role of Neuroplasticity in Development, Aging, and Neurodegeneration.Brain sciences · 2023Review
- New perspectives on sex differences in learning and memory.Trends in endocrinology and metabolism: TEM · 2023Review
- Article
- Sex Differences in the Relationship between Perceived Stress and Cognitive Trajectories.The American journal of geriatric psychiatry : official journal of the American Association for Geriatric Psychiatry · 2023Observational
- Sex differences in synaptic plasticity underlying learning.Journal of neuroscience research · 2023Review
- Hippocampus-based behavioral, structural, and molecular dynamics across the estrous cycle.Journal of neuroendocrinology · 2023Review
- Behavioral and transcriptomic effects of the cancer treatment tamoxifen in mice.Frontiers in neuroscience · 2023Article
- Temporal endurance of exercise-induced benefits on hippocampus-dependent memory and synaptic plasticity in female mice.Neurobiology of learning and memory · 2022Article
24 more citing papers are in PubMed but not listed here.
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Authors and funding
8 authors at 3 institutions in 1 country.
Funding
No grant is acknowledged in the PubMed record.
Abstract
Synaptic plasticity of the female hippocampus may cyclically fluctuate across the estrous cycle. The spine density fluctuation had been explained by fluctuation of plasma estradiol (E2) and progesterone (PROG), with the assumption that these steroids penetrate into the hippocampus. Recently, however, we demonstrated that male hippocampal levels of sex steroids are much higher than those in plasma, suggesting a weak contribution of plasma steroids to the spine density. By combination of mass-spectrometric analysis with HPLC-purification and picolinoyl-derivatization of hippocampal sex steroids, we determined the accurate concentration of E2 and PROG at four stages of plasma estrous cycle including Proestrus (Pro), Estrus (Est), Diestrus 1 (D1), and Diestrus 2 (D2). Hippocampal levels of E2 and PROG showed cyclic fluctuation with a peak at Pro for E2 and at D1 for PROG, having a positive correlation with the plasma estrous cycle. All these sex steroid levels are much higher in the hippocampus than in plasma. Even after ovariectomy a significant levels of E2 and PROG were observed in the hippocampus. The total spine density showed higher values at Pro and D1, and lower values at Est and D2, having a good correlation with the peak levels of hippocampal E2 or PROG. We also examined fluctuation of the head diameter of spines. Interestingly, mRNA expression level of steroidogenic enzymes (P450arom and 17β-HSD, etc.) and sex-steroid receptors did not significantly change across the estrous cycle. Therefore, the fluctuation of total hippocampal PROG (equal to sum of hippocampus-synthesized PROG and plasma PROG) may be originated from the contribution of cyclic change in plasma PROG, which can induce the fluctuation of total hippocampal E2, since steroid conversion activity of hippocampus might be nearly the same across the estrus cycle.
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Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.