Massari V J, Chan J, Chronwall B M, O'Donohue T L, Oertel W H, Pickel V M
Department of Pharmacology, Howard University Medical School, Washington, D.C.
J Neurosci Res. 1988 Feb;19(2):171-86. doi: 10.1002/jnr.490190202.
The ultrastructure, afferent input, and sites of termination of neurons containing neuropeptide Y-like immunoreactivity (NPY-LI) were examined in the adult rat nucleus accumbens by using the peroxidase-antiperoxidase (PAP) method. The NPY-LI was seen in sparsely distributed, spindle-shaped perikarya having cross-sectional diameters of 15-20 microns. These perikarya exhibited highly invaginated nuclear membranes and thin rims of cytoplasm containing Golgi lamellae, dense-core vesicles, and other organelles. A few large, principally aspiny, dendrites also showed NPY-LI. The dendrites received synaptic input from unlabeled terminals forming both symmetric and asymmetric junctions. Immunolabeling for NPY was evident in other processes that were not clearly differentiated as dendrites or axons. These were seen primarily near glial processes and the basal laminae of blood vessels. A few myelinated and many unmyelinated axons and axon terminals also were labeled for NPY. These terminals contained numerous, small (40-60 nm), clear and one or more large (80-100 nm) dense core vesicles. Forty-seven percent (27 out of 57) of the terminals containing NPY-LI formed symmetric junctions with unlabeled dendrites or dendritic spines. The remainder lacked recognizable densities within single planes of section. The neurons exhibiting NPY-LI in the nucleus accumbens were characterized further with respect to their afferent input from terminals labeled for the GABA-synthesizing enzyme, glutamic acid decarboxylase (GAD). Immunogold labeling of a rabbit antiserum against NPY and PAP labeling for a sheep antiserum to GAD were sequentially applied to the same sections. The GAD-labeled terminals formed symmetric junctions primarily with the more numerous unlabeled dendrites. However, a few synaptic junctions also were detected between the GAD-labeled terminals and dendrites showing immunogold labeling for NPY. We conclude (1) that in the rat nucleus accumbens, NPY-LI is found principally in neurons of the aspiny type and (2) that the output from these presumably intrinsic neurons to other neighboring neurons or blood vessels is at least partially modulated by GABA.
采用过氧化物酶抗过氧化物酶（PAP）法，对成年大鼠伏隔核中含有神经肽Y样免疫反应性（NPY-LI）的神经元的超微结构、传入输入及终末部位进行了研究。NPY-LI可见于散在分布的梭形胞体，其横径为15-20微米。这些胞体呈现高度内陷的核膜以及含有高尔基体板层、致密核心小泡和其他细胞器的薄细胞质边缘。少数大的、主要无棘的树突也显示NPY-LI。这些树突接受来自未标记终末的突触输入，形成对称和不对称连接。在未明确区分为树突或轴突的其他突起中，NPY免疫标记明显。这些主要见于神经胶质突起和血管基膜附近。少数有髓和许多无髓轴突及轴突终末也被标记为NPY。这些终末含有许多小（40-60纳米）的清亮小泡以及一个或多个大（80-100纳米）的致密核心小泡。47%（57个中有27个）含有NPY-LI的终末与未标记的树突或树突棘形成对称连接。其余的在单个切片平面内缺乏可识别的致密物。伏隔核中显示NPY-LI的神经元，就其来自标记有γ-氨基丁酸合成酶谷氨酸脱羧酶（GAD）的终末的传入输入而言，进一步进行了特征描述。将兔抗NPY抗血清的免疫金标记和羊抗GAD抗血清的PAP标记依次应用于同一切片。GAD标记的终末主要与较多的未标记树突形成对称连接。然而，在GAD标记的终末与显示NPY免疫金标记的树突之间也检测到少数突触连接。我们得出结论：（1）在大鼠伏隔核中，NPY-LI主要存在于无棘型神经元中；（2）这些可能为固有神经元向其他相邻神经元或血管的输出至少部分受γ-氨基丁酸调节。
