Seroogy K B, Fallon J H
Department of Anatomy and Neurobiology, University of California, Irvine 92717.
J Comp Neurol. 1989 Jan 15;279(3):415-35. doi: 10.1002/cne.902790307.
The purpose of the present study was to analyze the distribution of cholecystokininlike-immunoreactive (CCK-I) neurons within the rat ventral mesencephalon which project to several forebrain areas. The peroxidase-antiperoxidase immunocytochemical technique was used to examine the anatomical localization of CCK-I within the ventral midbrain and in the following forebrain regions: caudate-putamen, nucleus accumbens, olfactory tubercle, bed nucleus of the stria terminalis, septum, amygdala, and prefrontal, anterior cingulate, and piriform cortices. CCK-I perikarya were distributed throughout the substantia nigra, ventral tegmental area, and several midline raphe nuclei to a greater extent than previously reported, particularly in the substantia nigra pars compacta. Terminallike immunoreactivity for CCK was observed in all of the above forebrain sites. In addition, infrequent CCK-I cell bodies were localized in the caudate-putamen, nucleus accumbens, olfactory tubercle, septum, and bed nucleus of the stria terminalis. To analyze forebrain projections of the ventral midbrain CCK-I neurons, indirect immunofluorescence was combined with fluorescence retrograde tracing. CCK-I neurons of the substantia nigra and/or ventral tegmental area were found to project, to varying extents, to all of the above CCK-I forebrain terminal fields. The nucleus accumbens, olfactory tubercle, and septal and prefrontal cortical projections arose primarily from CCK-I perikarya in the ventral tegmental area whereas the projections to the caudate-putamen and anterior cingulate cortex arose predominantly from immunoreactive neurons in the substantia nigra pars compacta. The amygdala received innervation mainly from CCK-I cell bodies located in the substantia nigra pars lateralis. CCK-I afferents to the bed nucleus of the stria terminalis and piriform cortex originated from perikarya distributed approximately equally across the ventral tegmental area and substantia nigra pars compacta. The general topography of CCK-I forebrain innervation observed in this study is similar to that previously reported for the ascending dopaminergic projections from ventral mesencephalic neurons. CCK-I neurons of the midline raphe nuclei were found to provide relatively minor afferents to the caudate-putamen, bed nucleus of the stria terminalis, septum, and prefrontal cortex and more substantial projections to the amygdala. The results of this study demonstrate that CCK-I neurons of the ventral midbrain supply a much broader innervation of forebrain regions than previously appreciated.(ABSTRACT TRUNCATED AT 400 WORDS)
本研究的目的是分析大鼠中脑腹侧内胆囊收缩素样免疫反应性（CCK-I）神经元的分布，这些神经元投射至多个前脑区域。采用过氧化物酶-抗过氧化物酶免疫细胞化学技术，检查腹侧中脑及以下前脑区域内CCK-I的解剖定位：尾状核-壳核、伏隔核、嗅结节、终纹床核、隔区、杏仁核以及前额叶、前扣带回和梨状皮质。CCK-I胞体在黑质、腹侧被盖区和几个中线中缝核中的分布比先前报道的范围更广，尤其是在黑质致密部。在上述所有前脑部位均观察到CCK的终末样免疫反应性。此外，在尾状核-壳核、伏隔核、嗅结节、隔区和终纹床核中偶尔可见CCK-I细胞体。为了分析中脑腹侧CCK-I神经元的前脑投射，将间接免疫荧光与荧光逆行追踪相结合。发现黑质和/或腹侧被盖区的CCK-I神经元不同程度地投射至上述所有CCK-I前脑终末区域。伏隔核、嗅结节以及隔区和前额叶皮质的投射主要来自腹侧被盖区内的CCK-I胞体，而尾状核-壳核和前扣带回皮质的投射主要来自黑质致密部的免疫反应性神经元。杏仁核主要接受来自黑质外侧部CCK-I细胞体的神经支配。终纹床核和梨状皮质的CCK-I传入纤维起源于腹侧被盖区和黑质致密部中分布大致相等的胞体。本研究中观察到的CCK-I前脑神经支配的总体分布图与先前报道的腹侧中脑神经元的多巴胺能上行投射图相似。发现中缝核的CCK-I神经元对尾状核-壳核、终纹床核、隔区和前额叶皮质提供相对较少的传入纤维，而对杏仁核的投射较多。本研究结果表明，中脑腹侧的CCK-I神经元对前脑区域的神经支配范围比先前认为的要广泛得多。（摘要截选至400字）
