French Sarah Jane, Hailstone Julia Catherine, Totterdell Susan
Department of Pharmacology, University of Oxford, Mansfield Road, Oxford OX1 3QT, UK.
Brain Res. 2003 Aug 15;981(1-2):160-7. doi: 10.1016/s0006-8993(03)03017-8.
The basolateral amygdala and the ventral subiculum of the hippocampal formation are two of the major limbic-related regions within the brain, both of which project heavily to the nucleus accumbens. The nucleus accumbens is regarded as the limbic-motor interface, in view of these limbic afferent and its somatomotor and autonomic efferent connections. These afferent inputs have been suggested to converge monosynaptically on cells within the accumbens and are hypothesised to play a role in functions such as affective motivational behaviour. Convergence between inputs from the basolateral amygdala and the hippocampus at the level of the accumbens can be demonstrated with electrophysiological recording methods, but these do not conclusively preclude polysynaptic mechanisms. In fact there is a robust reciprocal projection between the basolateral amygdala and the hippocampus, synaptic details of which have not been fully investigated. We examined the synaptic input from the basolateral amygdala to the projection neurons of the subiculum, the spiny pyramidal neurons. We labelled the afferents from basolateral amygdala with a small injection of biotinylated dextran amine, and revealed the anterogradely labeled fibers within the subiculum. The labeled basolateral amygdala fibers were studied with electron microscopy to identify their postsynaptic target structures. With this technique we have demonstrated anatomically that the basolateral amygdala preferentially innervates spiny subiculum neurons, presumed pyramidal projection neurons, although some dendrites and possibly local circuit neurons may be targeted.
基底外侧杏仁核和海马结构的腹侧下托是大脑中两个主要的边缘系统相关区域，两者都大量投射到伏隔核。鉴于这些边缘系统传入纤维及其躯体运动和自主传出连接，伏隔核被视为边缘系统 - 运动接口。这些传入输入被认为单突触汇聚于伏隔核内的细胞，并被假设在诸如情感动机行为等功能中发挥作用。可以用电生理记录方法证明来自基底外侧杏仁核和海马的输入在伏隔核水平的汇聚，但这些方法并不能确凿地排除多突触机制。事实上，基底外侧杏仁核和海马之间存在强大的相互投射，其突触细节尚未得到充分研究。我们研究了从基底外侧杏仁核到下托投射神经元（棘状锥体神经元）的突触输入。我们通过小剂量注射生物素化葡聚糖胺标记来自基底外侧杏仁核的传入纤维，并在下托中显示出顺行标记的纤维。用电子显微镜研究标记的基底外侧杏仁核纤维，以确定其突触后靶结构。通过这项技术，我们在解剖学上证明了基底外侧杏仁核优先支配棘状下托神经元，推测为锥体投射神经元，尽管一些树突以及可能的局部回路神经元也可能是其靶标。
