Departments of Physiology and Geriatric Medicine, and Reynolds Oklahoma Center on Aging, University of Oklahoma Health Sciences Center, Oklahoma City, OK 73104, USA.
Eur J Neurosci. 2011 Jul;34(2):283-91. doi: 10.1111/j.1460-9568.2011.07743.x. Epub 2011 Jun 27.
The classic steroid hormone estradiol is rapidly produced by central auditory neurons in the songbird brain and instantaneously modulates auditory coding to enhance the neural and behavioral discrimination of acoustic signals. Although recent advances highlight novel roles for estradiol in the regulation of central auditory processing, current knowledge on the functional and neurochemical organization of estrogen-associated circuits, as well as the impact of sensory experience in these auditory forebrain networks, remains very limited. Here we show that both estrogen-producing and -sensitive neurons are highly expressed in the caudomedial nidopallium (NCM), the zebra finch analog of the mammalian auditory association cortex, but not other auditory forebrain areas. We further demonstrate that auditory experience primarily engages estrogen-producing, and to a lesser extent, estrogen-responsive neurons in NCM, that these neuronal populations moderately overlap and that acute episodes of sensory experience do not quantitatively affect these circuits. Finally, we show that whereas estrogen-producing cells are neurochemically heterogeneous, estrogen-sensitive neurons are primarily glutamatergic. These findings reveal the neurochemical and functional organization of estrogen-associated circuits in the auditory forebrain, demonstrate their activation and stability in response to sensory experience in behaving animals, and highlight estrogenic circuits as fundamental components of central networks supporting sensory processing.
经典的甾体激素雌二醇是由鸣禽大脑中的中枢听觉神经元迅速产生的，并即时调节听觉编码，以增强对声信号的神经和行为辨别能力。尽管最近的进展强调了雌二醇在调节中枢听觉处理中的新作用，但目前关于雌激素相关回路的功能和神经化学组织，以及这些听觉前脑网络中感觉经验的影响的知识仍然非常有限。在这里，我们表明，产雌激素和雌激素敏感的神经元在尾侧中脑背侧（NCM）中高度表达，NCM 是鸣禽听觉联合皮层的哺乳动物类似物，但不在其他听觉前脑区域中表达。我们进一步证明，听觉经验主要涉及 NCM 中的产雌激素神经元，并且在较小程度上涉及雌激素反应性神经元，这些神经元群体适度重叠，并且急性感觉经验不会对这些回路产生定量影响。最后，我们表明，虽然产雌激素细胞具有神经化学异质性，但雌激素敏感神经元主要是谷氨酸能的。这些发现揭示了听觉前脑雌激素相关回路的神经化学和功能组织，证明了它们在行为动物对感觉经验的反应中的激活和稳定性，并强调了雌激素回路作为支持感觉处理的中枢网络的基本组成部分。
