大鼠纹状体Patch和Matrix间区及其神经元形态学特征的观察

Experimental Observation of Morphological Traits on Striatal Patch-Matrix Compartments and Their Neurons in Rats

【目的】纹状体Patch和Matrix间区被证实与神经精神活动和躯体运动有关。本实验旨在探测Patch和Matrix间区及其神经元的形态学特征,为研究纹状体-Patch和-Matrix神经元的通路联系提供资料。【方法】成年雄性SD大鼠分别按照常规和电镜要求灌注固定、取脑和后固定;半导体或振动切片之后进行免疫组化PAP方法单标记和双标记;光镜下分别用Photoshop软件测量Patch和Matrix间区的面积并计算百分比;光镜和电镜下观察阳性神经元的结构;实验数据用SPSS软件统计处理。【结果】①Mor阳性的Patch间区呈不规则形的斑块状散在分布于纹状体,在胼胝体深方存在一条恒定的阳性带状区。Patch间区占纹状体面积的9%,其面积在纹状体的头侧明显大于尾侧(P<0.05)。阳性结构呈细丝或絮状,阳性胞体不明显。②Calb阳性的Matrix间区在纹状体内侧区染色较深,可见明显不规则的淡染色区,其形状与相邻片的Patch间区一致。Matrix间区的面积明显大于Patch间区(P<0.05)。可见阳性树突和树突棘,但阳性胞体不明显。③电镜下分别可见Mor和Calb阳性树突和树突棘,其大多数接受兴奋性突触连接,而与阳性树突形成的突触多为穿孔型。抑制性突触少见,阳性胞体不明显。【结论】头侧纹状体密集分布的Patch间区、内侧纹状体Calb强烈反应,和阳性标记的树突、树突棘以及兴奋性突触为主的形态学特征,提示Mor和Calb阳性神经元分别具有特异性的神经通路连接和生理机能。

[Objective] To explore the morphological traits of Patch-Matrix compartments and their neurons and to provide experimental mainstay for the study of Patch-Matrix nervous pathways. [Methods] Striatal Patch-Matrix compartments were considered to be involved in neuropsychiatrie and somatosensorimotor actions. Adult male SD rats were fixed by perfusion fixation and the brains were removed according to the routine and electron microscopic requirements. The sections were conducted either with a Semiconductor-frozen mierotome or with a vibratome, and then were single-labelled and double-labelled using immunohistoehemieal PAP method. Soon after that, areas and percentages of Patch-Matrix compartments were measured and calculated with Photoshop software under light microscope. The structures of positive neurons were observed under light and electron microscope. Experimental data were dealt with SPSS software. [Results] （1） μ-opioid receptor （Mor） positive Patch compartment was seen in a heterogeneous patchy distribution in striatum, and a constant positive zonal area presented in corpus callosum. The Patch compartment area accounted for 9% of striatal area, and was bigger in rostral striatum than in caudal striatum （P 〈 0.05）. The positive structures in Patches appeared to be filament and flocculent and no positive perikarya was observed. （2） Calbindin （Calb） positive Matrix compartment appeared in whole striatum, and was more intense in the medial striatum than in the lateral striatum. Irregular slightly stained area was observed and its shape was consistent with the adjacent Patch compartment,but the area of Matrix compartment was obviously larger than that of Patch compartment （P 〈 0.05）. Positive dendrites and dendritic spines could be obviously observed by high-power light microscopy, but positive perikarya could not. （3） Both Mor and Calb positive immunoreactivity （IR） were predominantly localized in dendrites and dendritic spines which were observed under electronic microscopy （EM）, and the majority of synapses formed with positive dendrites was perforated postsynaptic density （PSD）. Inhibitory synapse was rare and positive perikarya was not obvious. [Conclusions] The morphological characteristics of dense distribution of Mor IR in rostral striatum in Patch compartment, intense Calb-labeling in the medial striatum, formation of asymmetric synapses for positive dendrites and dendritic spines, and present of perforated PSD on positive dendrites indicate that Mot and Calb positive neurons possess the special nervous pathways and physiological function respectively.