Carnes K M, Fuller T A, Price J L
Department of Anatomy, Washington University School of Medicine, St. Louis, Missouri 63110.
J Comp Neurol. 1990 Dec 22;302(4):824-52. doi: 10.1002/cne.903020413.
The distribution of presumptive glutamatergic and/or aspartatergic neurons retrogradely labeled following injections of [3H]-D-aspartate into the magnocellular basal forebrain of the rat was compared with the distribution of neurons labeled by comparable injections of the nonspecific retrograde axonal tracer wheat germ agglutinin conjugated to horseradish peroxidase. Cells retrogradely labeled by wheat germ agglutinin-horseradish peroxidase were found in a wide range of limbic and limbic-related structures in the forebrain and brainstem. In the telencephalon, labeled neurons were seen in the orbital, medial prefrontal, and agranular insular cortical areas, the amygdaloid complex, and the hippocampal formation. Labeled cells were also seen in the olfactory cortex, the lateral septum, the ventral striatopallidal region, and the magnocellular basal forebrain itself. In the diencephalon, neurons were labeled in the midline nuclear complex of the thalamus, the lateral habenular nucleus, and the hypothalamus. In the brainstem, labeled cells were found bilaterally in the ventral midbrain, the central gray, the reticular formation, the parabrachial nuclei, the raphe nuclei, the laterodorsal tegmental nucleus, and the locus coeruleus. A significant fraction of the afferents to the magnocellular basal forebrain appear to be glutamatergic and/or aspartatergic. Only a few of the regions labeled with wheat germ agglutinin-horseradish peroxidase were not also labeled with [3H]-D-aspartate in the comparable experiments. Most prominent among the non-glutamatergic/aspartatergic projections were those from fields CA1 and CA3 of the hippocampus, the hilus of the dentate gyrus, the dorsal subiculum, the tuberomammillary nucleus, and the ventral pallidum. In addition, most of the lateral hypothalamic and brainstem projections to the magnocellular basal forebrain were not significantly labeled with [3H]-D-aspartate. In addition to these inputs, a commissural projection from the region of the contralateral nucleus of the horizontal limb of the diagonal band was confirmed with both wheat germ agglutinin-horseradish peroxidase and the anterograde axonal tracer Phaseolus vulgaris leucoagglutinin. This projection did not label with [3H]-D-aspartate or [3H]-GABA, suggesting that it is not glutamatergic/aspartatergic or GABAergic. Furthermore, double labeling experiments with the fluorescent retrograde tracer True Blue and antibodies against choline acetyltransferase indicate that the projection is not cholinergic.
将[3H]-D-天冬氨酸注射到大鼠大细胞基底前脑后，对逆行标记的推测性谷氨酸能和/或天冬氨酸能神经元的分布，与注射了与辣根过氧化物酶偶联的非特异性逆行轴突示踪剂小麦胚凝集素后标记的神经元分布进行了比较。用小麦胚凝集素-辣根过氧化物酶逆行标记的细胞在前脑和脑干的广泛边缘和边缘相关结构中被发现。在端脑，标记的神经元见于眶额、内侧前额叶和无颗粒岛叶皮质区、杏仁复合体和海马结构。标记的细胞也见于嗅皮质、外侧隔、腹侧纹状体苍白球区和大细胞基底前脑本身。在间脑，神经元在丘脑的中线核复合体、外侧缰核和下丘脑被标记。在脑干，标记的细胞在双侧腹侧中脑、中央灰质、网状结构、臂旁核、中缝核、外侧背侧被盖核和蓝斑中被发现。投射到大细胞基底前脑的传入纤维中有很大一部分似乎是谷氨酸能和/或天冬氨酸能的。在可比实验中，用小麦胚凝集素-辣根过氧化物酶标记的区域中，只有少数区域没有被[3H]-D-天冬氨酸标记。在非谷氨酸能/天冬氨酸能投射中最突出的是来自海马CA1和CA3区、齿状回门、背侧下托、乳头体核和腹侧苍白球的投射。此外，大部分外侧下丘脑和脑干向大细胞基底前脑的投射没有被[3H]-D-天冬氨酸显著标记。除了这些输入，用小麦胚凝集素-辣根过氧化物酶和顺行轴突示踪剂菜豆白细胞凝集素都证实了来自对侧斜角带水平支核区域的连合投射。该投射没有被[3H]-D-天冬氨酸或[3H]-GABA标记，表明它不是谷氨酸能/天冬氨酸能或GABA能的。此外，用荧光逆行示踪剂真蓝和抗胆碱乙酰转移酶抗体进行的双重标记实验表明该投射不是胆碱能的。
