España Rodrigo A, Berridge Craig W
Psychology Department, University of Wisconsin, Madison, 53706, USA.
J Comp Neurol. 2006 Jun 10;496(5):668-83. doi: 10.1002/cne.20946.
Norepinephrine acts within select basal forebrain regions to modulate behavioral state and/or state-dependent processes, including the general regions encompassing the medial septal area, the medial preoptic area, and the substantia innominata. The present study examined the origin and organization of noradrenergic efferents to these basal forebrain regions by using combined immunohistochemical identification of noradrenergic neurons with retrograde tracing. Results indicate that the locus coeruleus provides the majority of noradrenergic input to these regions. Lesser, although at times substantial, contributions from the A1/C1 and A2/C2 adrenergic cell groups were also observed, particularly in the case of the medial preoptic region. Given the prominent state-modulating actions of the locus coeruleus, additional studies examined: 1) lateralization of locus coeruleus efferents to these regions; 2) the topographical organization of basal forebrain-projecting locus coeruleus neurons; and 3) the degree of collateralization of individual locus coeruleus neurons across these regions. Approximately 80-85% of locus coeruleus efferents to these regions project ipsilaterally. In general, basal forebrain-projecting neurons were distributed throughout the entire dorsoventral and rostrocaudal extent of the locus coeruleus. Additionally, a large proportion of locus coeruleus neurons project simultaneously to these basal forebrain terminal fields. Combined, these observations indicate coordinated actions of locus coeruleus neurons across these basal forebrain regions implicated in the regulation of behavioral state and/or state-dependent processes.
去甲肾上腺素在特定的基底前脑区域发挥作用，以调节行为状态和/或与状态相关的过程，包括内侧隔区、内侧视前区和无名质等大致区域。本研究通过联合使用去甲肾上腺素能神经元的免疫组织化学鉴定和逆行追踪，研究了去甲肾上腺素能传出纤维至这些基底前脑区域的起源和组织。结果表明，蓝斑为这些区域提供了大部分去甲肾上腺素能输入。还观察到来自A1/C1和A2/C2肾上腺素能细胞群的贡献较少，尽管有时也相当可观，特别是在内侧视前区的情况下。鉴于蓝斑突出的状态调节作用，进一步的研究考察了：1）蓝斑传出纤维至这些区域的侧化；2）投射至基底前脑的蓝斑神经元的拓扑组织；3）单个蓝斑神经元在这些区域的侧支化程度。约80 - 85%至这些区域的蓝斑传出纤维向同侧投射。一般来说，投射至基底前脑的神经元分布在蓝斑整个背腹侧和前后侧范围。此外，很大一部分蓝斑神经元同时投射至这些基底前脑终末场。综合来看，这些观察结果表明蓝斑神经元在这些与行为状态和/或与状态相关过程的调节有关的基底前脑区域发挥协同作用。
