Abstract：
Estrogen plays a crucial role in regulating various brain functions, including cognitive, emotional, and social behaviors. Menopausal women face a decline in estrogen levels, which has been linked to several physical and mental health issues. However, the impact of estrogen on the olfactory bulb-nucleus accumbens (OB-NAc) circuit, which is essential for regulating emotions and cognitive behaviors, remains poorly understood. To test the hypothesis that estrogen deficiency affects signal processing, we recorded local field potentials (LFPs) using intracranial electrodes implanted in four-week-old ovariectomized (OVX) mice during an open-field test (OFT). The results showed a decrease in locomotor activity and increase in anxiety-like behaviors in OVX mice. Furthermore, we found a decrease in high-gamma power in the OB. We analyzed coherence and inter-region phase-amplitude coupling (ir-PAC) to explore the connectivity between the OB and NAc. We observed a decrease in low-gamma and high-gamma coherence in OVX mice. Additionally, we found that the direction of connectivity from the NAc to the OB was disrupted in OVX mice. In summary, our study provides evidence that estrogen deficiency is linked to synchronized neural connectivity changes in the OB-NAc circuit. These findings have implications for our understanding of the roles played by the OB-NAc neural circuit and estrogen in the regulation of general exploratory behavior and anxiety-like behavior.
摘要：
雌激素在调节各种脑功能中起着至关重要的作用,包括认知，情感,和社会行为。更年期女性面临雌激素水平下降，这与几个身体和心理健康问题有关。然而,雌激素对嗅球-伏隔核（OB-NAc）回路的影响，这对于调节情绪和认知行为至关重要，仍然知之甚少。为了检验雌激素缺乏影响信号处理的假设，我们在开场试验(OFT)期间使用植入4周龄卵巢切除(OVX)小鼠的颅内电极记录局部场电位(LFP).结果表明，OVX小鼠的运动活动减少，焦虑样行为增加。此外，我们发现OB的高伽马功率降低。我们分析了相干性和区域间相位-振幅耦合（ir-PAC），以探索OB和NAc之间的连通性。我们观察到OVX小鼠的低γ和高γ相干性降低。此外,我们发现,在OVX小鼠中,从NAc到OB的连接方向被破坏.总之,我们的研究提供了雌激素缺乏与OB-NAc回路中同步的神经连接变化相关的证据.这些发现对我们理解OB-NAc神经回路和雌激素在调节一般探索行为和焦虑样行为中的作用具有启示意义。
