Sockman Keith W, Salvante Katrina G
Department of Biology, University of North Carolina, Chapel Hill, North Carolina 27599-3280, USA.
Dev Neurobiol. 2008 Apr;68(5):656-68. doi: 10.1002/dneu.20611.
Mate choice is among the most consequential decisions a sexually reproducing organism can make. In many songbird species, females make mate-choice decisions based, in part, on variation between males in songs that reflect their quality. Importantly, females may adjust their choice relative to the prevalence of high quality songs. In European starlings (Sturnus vulgaris), females prefer males that primarily sing long songs over those that primarily sing short songs, and sensitivity of the auditory telencephalon to song length depends on the prevalence of long songs in the environment. Several lines of evidence suggest a role for noradrenergic innervation of the auditory telencephalon in mediating this neuro- and behavioral plasticity. To simulate variation in quality of the song environment, we exposed adult female starlings to 1 week of either long or short songs and then quantified several monoamines and their metabolites in the caudomedial mesopallium and caudomedial nidopallium (NCM) using high performance liquid chromatography. We also used immunocytochemistry to assess these areas for immunoreactive dopamine-beta-hydroxylase (DBH-ir), the enzyme that synthesizes norepinephrine. We found that long songs elevated levels of the principal norepinephrine metabolite, the principal dopamine metabolite, and the probability of DBH-ir in the NCM compared to short songs. Song environment did not appear to influence norepinephrine or dopamine levels. Thus, the quality of the song environment regulates the local secretion of catecholamines, particularly norepinephrine, in the female auditory telencephalon. This may form a basis for plasticity in forebrain sensitivity and mate-choice behavior based on the prevalence of high-quality males.
配偶选择是有性繁殖生物所能做出的最重要的决定之一。在许多鸣禽物种中，雌性做出配偶选择决定部分是基于雄性歌声的差异，而歌声能反映它们的品质。重要的是，雌性可能会根据高质量歌声的普遍程度来调整自己的选择。在欧洲椋鸟（Sturnus vulgaris）中，雌性更喜欢主要唱长歌的雄性，而不是主要唱短歌的雄性，并且听觉端脑对歌声长度的敏感度取决于环境中长歌的普遍程度。有几条证据表明，听觉端脑的去甲肾上腺素能神经支配在介导这种神经和行为可塑性方面发挥作用。为了模拟歌声环境质量的变化，我们让成年雌性椋鸟接触1周的长歌或短歌，然后使用高效液相色谱法对尾内侧中脑皮层和尾内侧巢皮层（NCM）中的几种单胺及其代谢物进行定量。我们还使用免疫细胞化学方法评估这些区域中多巴胺β-羟化酶免疫反应性（DBH-ir），该酶能合成去甲肾上腺素。我们发现，与短歌相比，长歌提高了NCM中主要去甲肾上腺素代谢物、主要多巴胺代谢物的水平以及DBH-ir的概率。歌声环境似乎并未影响去甲肾上腺素或多巴胺的水平。因此，歌声环境的质量调节了雌性听觉端脑中儿茶酚胺的局部分泌，特别是去甲肾上腺素。这可能构成了基于高质量雄性普遍程度的前脑敏感度和配偶选择行为可塑性的基础。
