Day H E, Curran E J, Watson S J, Akil H
Mental Health Research Institute, University of Michigan, Ann Arbor, Michigan 48109, USA.
J Comp Neurol. 1999 Oct 11;413(1):113-28.
The lateral division of the central nucleus of the amygdala (CEAl) and the oval nucleus of the bed nucleus of the stria terminalis (BSTov) have been linked closely anatomically and functionally. To determine whether these regions may be subdivided further on a neurochemical basis, dual in situ hybridization was used to determine the colocalization of corticotropin-releasing hormone (CRH), enkephalin (ENK), or neurotensin (NT) with glutamic acid decarboxylase isoforms 65 and 67 [used concurrently as a marker for gamma-aminobutyric acid GABA] in these nuclei. It was found that, for both regions, each peptide invariably was localized in a GABAergic cell. Although there was a similar overlap in the distribution of NT with ENK in the BSTov and CEAl, it was observed that CRH and ENK rarely were colocalized in either nucleus. To determine whether these distinct neuronal populations could be activated differentially, male rats were given a systemic injection of interleukin-1beta (IL-1beta; 5 microg/kg, i.p.), a stimulus that results in a robust increase in c-fos mRNA expression in the BSTov and CEAl. The neurochemical identity of these activated neurons showed striking similarities between the BSTov and the CEAl; All IL-1beta-responsive cells were GABAergic, the majority of c-fos- positive cells expressed ENK mRNA (BSTov, 81%; CEAl, 94%), and some expressed NT mRNA (BSTov, 23%; CEAl, 22%), whereas very few expressed CRH mRNA (BSTov, 4%; CEAl, 1%). These data provide evidence for the existence of discrete neural circuits within the BSTov and CEAl, and the similarities in the patterns of neurochemical colocalization in these nuclei are consistent with the concept of an extended amygdala. Furthermore, these data indicate that intraperitoneal IL-1beta recruits neurochemically distinct pathways within the BSTov and CEAl, and it is suggested that this differential activation may mediate specific aspects of immune, limbic, and/or autonomic processes.
杏仁核中央核外侧部（CEAl）与终纹床核椭圆核（BSTov）在解剖学和功能上紧密相连。为了确定这些区域在神经化学基础上是否可进一步细分，采用双重原位杂交法来确定促肾上腺皮质激素释放激素（CRH）、脑啡肽（ENK）或神经降压素（NT）与谷氨酸脱羧酶同工型65和67（同时用作γ-氨基丁酸GABA的标志物）在这些核中的共定位情况。结果发现，对于这两个区域，每种肽均始终定位于GABA能细胞中。虽然在BSTov和CEAl中NT与ENK的分布存在类似的重叠，但观察到CRH和ENK在任一核中很少共定位。为了确定这些不同的神经元群体是否能被差异性激活，给雄性大鼠腹腔注射白细胞介素-1β（IL-1β；5微克/千克，腹腔注射），该刺激会导致BSTov和CEAl中c-fos mRNA表达显著增加。这些被激活神经元的神经化学特征在BSTov和CEAl之间显示出惊人的相似性；所有对IL-1β有反应的细胞都是GABA能的，大多数c-fos阳性细胞表达ENK mRNA（BSTov，81%；CEAl，94%），一些表达NT mRNA（BSTov，23%；CEAl，22%），而很少有细胞表达CRH mRNA（BSTov，4%；CEAl，1%）。这些数据为BSTov和CEAl内存在离散神经回路提供了证据，并且这些核中神经化学共定位模式的相似性与扩展杏仁核的概念一致。此外，这些数据表明腹腔注射IL-1β会在BSTov和CEAl内募集神经化学上不同的通路，并且有人提出这种差异性激活可能介导免疫、边缘和/或自主过程的特定方面。
