García-López Margarita, Abellán Antonio, Legaz Isabel, Rubenstein John L R, Puelles Luis, Medina Loreta
Department of Human Anatomy, Faculty of Medicine, University of Murcia, 30100 Murcia, Spain.
J Comp Neurol. 2008 Jan 1;506(1):46-74. doi: 10.1002/cne.21524.
The amygdala controls emotional and social behavior and regulates instinctive reflexes such as defense and reproduction by way of descending projections to the hypothalamus and brainstem. The descending amygdalar projections are suggested to show a cortico-striato-pallidal organization similar to that of the basal ganglia (Swanson [2000] Brain Res 886:113-164). To test this model we investigated the embryological origin and molecular properties of the mouse centromedial and extended amygdalar subdivisions, which constitute major sources of descending projections. We analyzed the distribution of key regulatory genes that show restricted expression patterns within the subpallium (Dlx5, Nkx2.1, Lhx6, Lhx7/8, Lhx9, Shh, and Gbx1), as well as genes considered markers for specific subpallial neuronal subpopulations. Our results indicate that most of the centromedial and extended amygdala is formed by cells derived from multiple subpallial subdivisions. Contrary to a previous suggestion, only the central--but not the medial--amygdala derives from the lateral ganglionic eminence and has striatal-like features. The medial amygdala and a large part of the extended amygdala (including the bed nucleus of the stria terminalis) consist of subdivisions or cell groups that derive from subpallial, pallial (ventral pallium), or extratelencephalic progenitor domains. The subpallial part includes derivatives from the medial ganglionic eminence, the anterior peduncular area, and possibly a novel subdivision, called here commissural preoptic area, located at the base of the septum and related to the anterior commissure. Our study provides a molecular and morphological foundation for understanding the complex embryonic origins and adult organization of the centromedial and extended amygdala.
杏仁核控制情绪和社会行为，并通过向下丘脑和脑干的投射来调节诸如防御和繁殖等本能反射。杏仁核的下行投射被认为呈现出与基底神经节类似的皮质-纹状体-苍白球组织（斯旺森[2000年]《脑研究》886:113 - 164）。为了验证这一模型，我们研究了构成下行投射主要来源的小鼠中央内侧和扩展杏仁核亚区的胚胎起源和分子特性。我们分析了在皮质下结构中呈现限制性表达模式的关键调控基因（Dlx5、Nkx2.1、Lhx6、Lhx7/8、Lhx9、Shh和Gbx1）的分布，以及被认为是特定皮质下神经元亚群标志物的基因。我们的结果表明，大部分中央内侧和扩展杏仁核由来自多个皮质下亚区的细胞形成。与之前的观点相反，只有中央杏仁核——而非内侧杏仁核——源自外侧神经节隆起并具有纹状体样特征。内侧杏仁核和扩展杏仁核的大部分（包括终纹床核）由源自皮质下、皮质（腹侧皮质）或脑外祖细胞区域的亚区或细胞群组成。皮质下部分包括来自内侧神经节隆起、前连合区的衍生物，以及可能一个新的亚区，在此称为连合前视区，位于隔膜底部并与前连合相关。我们的研究为理解中央内侧和扩展杏仁核复杂的胚胎起源和成年组织提供了分子和形态学基础。
