Estrogen contributes to seasonal plasticity of the adult avian song control system
Estrogen contributes to seasonal plasticity of the adult avian song control system
复制标题
DOI：
10.1002/neu.10288
复制
发表时间：
2004-02-15
期刊：
影响因子：
--
通讯作者：
Brenowitz, EA
中科院分区：
文献类型：
--
作者：
Soma, KK;Tramontin, AD;Brenowitz, EA
鸣禽成年后表现出惊人的神经可塑性，包括控制鸣叫行为产生的离散大脑区域（“鸣叫控制核”）的大规模解剖变化。几种鸣声控制核的体积在繁殖期比非繁殖期大得多，这些季节性神经变化受血浆睾酮(T)水平的调节。在许多情况下，T对中枢神经系统的影响是通过芳香化酶介导的神经转化为雌二醇（E-2）。雄性鸣禽的前脑表达非常高水平的芳香酶，在某些情况下邻近鸣叫控制核。本研究以野生雄性鸣禽为研究对象，在繁殖期和非繁殖期分别研究了芳香化酶抑制和雌激素对鸣禽鸣叫核大小的影响。在繁殖期雄性中，芳香化酶抑制导致端脑歌唱控制核（HVC）的体积减少，这种影响可以通过同时补充雌激素来部分恢复。在非育种雄性中，雌二醇处理使HVC在2周内生长到最大的春季大小。综上所述，这些数据表明T的芳构化是鸣禽控制系统可塑性的重要中介，雌二醇在成年雄性鸣禽中具有神经营养作用。本研究在大体解剖尺度上证明了雌激素对成体神经可塑性的影响，首次对雌性激素对野生动物大脑的影响进行了研究。(C) 2003 Wiley期刊有限公司中国生物医学工程杂志（英文版），2004,31(4):444 - 444。
Songbirds show dramatic neural plasticity as adults, including large-scale anatomical changes in discrete brain regions ("song control nuclei") controlling the production of singing behavior. The volumes of several song control nuclei are much larger in the breeding season than in the nonbreeding season, and these seasonal neural changes are regulated by plasma testosterone (T) levels. In many cases, the effects of T on the central nervous system are mediated by neural conversion to estradiol (E-2) by the enzyme aromatase. The forebrain of male songbirds expresses very high levels of aromatase, in some cases adjacent to song control nuclei. We examined the effects of aromatase inhibition and estrogen treatment on song nuclei size using wild male songbirds in both the breeding and nonbreeding seasons. In breeding males, aromatase inhibition caused the volume of a telencephalic song control nucleus (HVC) to decrease, and this effect was partially rescued by concurrent estrogen replacement. In nonbreeding males, estradiol treatment caused HVC to grow to maximal spring size within 2 weeks. Overall, these data suggest that aromatization of T is an important mediator of song control system plasticity, and that estradiol has neurotrophic effects in adult male songbirds. This study demonstrates that estrogen can affect adult neural plasticity on a gross anatomical scale and is the first examination of estrogen effects on the brain of a wild animal. (C) 2003 Wiley Periodicals, Inc. J Neurobiol 58: 413-422, 2004.