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目的观察Ⅰ型和Ⅱ型囊泡膜谷氨酸转运体(VGluT1和VGluT2)在大鼠、猫和猴脊髓内的定位分布.方法免疫组织化学技术. 结果 VGluT1和VGluT2在大鼠、猫和猴脊髓灰质内均有分布.VGluT1在大鼠和猫脊髓背角Ⅱ层内侧部(ⅡI)及Ⅲ～Ⅵ层的内侧部分布最为密集,在Ⅰ层和Ⅱ层外侧部(Ⅱo)的分布较稀疏,其他层能观察到中等密度的分布.而在猴脊髓,VGluT1的分布与大鼠和猫有所不同,Ⅰ层、ⅡI层、Ⅲ层及Ⅳ～Ⅵ层内侧部分布最密集,在Ⅱ o层及Ⅳ～Ⅵ层外侧部较稀疏,甚至观察不到阳性结构.在猴的脊髓前角,仅在Ⅸ层观察到较稀疏的阳性产物,而其他层未见阳性产物.除此之外,在猴的脊髓后索内侧部能见到散在的阳性结构,而在大鼠和猫未观察到.VGluT2阳性产物在3种动物脊髓灰质内均呈中等强度的分布,其中在Ⅰ层、Ⅱ层和Ⅹ层内呈密集分布,在Ⅲ～Ⅵ层内侧分布较稀疏.在猴的背角深层外侧部,阳性产物非常少.在大鼠的外侧脊核(LSN)能见到中等强度的VGluT2阳性产物,而在猫和猴中并未观察到.在3种动物脊髓中,VGluT1和VGluT2阳性产物均呈点状分布. 结论 VGluT1和VGluT2在3种动物脊髓内均有分布,但其分布有一定的种属差异.提示它们可能在不同动物脊髓兴奋性神经元的活动中发挥重要作用.“,”Objective To investigate the distribution of the vesicular glutamate transporters (VGluTs), VGIuT1 and VGIuT2, in the spinal cord in multiple species, including rat, cat and monkey. Methods An immunohistochemical technique was used in the present study. Results VGluTs were observed in the gray matter of the spinal cord of rat, cat and monkey. VGluTl-immunoreactivity (VGluT1-IR) was most intense in the inner part of lamina Ⅱ(Ⅱ I) and the medial parts of laminae Ⅲ-Ⅵ of the spinal dorsal horn; weak in lamina Ⅰ and outer part of lamina Ⅱ(Ⅱ o); moderate in other parts in the rat and cat. The laminar distribution of VGluT1-IR in the spinal cord in the monkey is different from those in the rat and cat. The VGluT1-immunopositive product was intense in laminae Ⅰ, Ⅱ I, Ⅲ and the medial parts of laminae Ⅳ-Ⅵ of the spinal dorsal horn; weak to absent in lamina Ⅱ o and the lateral parts of laminae Ⅳ-Ⅵ of the dorsal horn. In the spinal anterior horn of monkey, the VGluT1-immunoreactive profiles were observed sparsely just in lamina Ⅸ, not in other laminae. At the same time, some scattered immunoreactive profiles were present in the white matter, particularly at the medial parts of the dorsal column in monkey, but not in rat and cat. On the other hand, VGluT2 immunoreactivity (VGluT2-IR) was moderately present throughout the gray matter, it was most dense in laminae Ⅰ-Ⅱ and Ⅹ, and weak in the medial parts of the deep spinal dorsal horn (laminae Ⅲ-Ⅵ) in the three species. The VGluT2-immunopositive product was very sparse in the lateral parts of the deep spinal dorsal horn of the monkey. In the lateral spinal nuclei of the rat, moderate VGluT2-immunopositive product could be seen, but not in the cat and monkey. In three species, both VGluT1- and VGluT2-IR showed a punctuate distribution. Conclusion The present results indicated that VGluT1 and VGluT2 were expressed in the spinal cord in all species examined but differentially distributed in a species-specific manner, and they might play an important role in the activities of the excitatory neurons in the spinal cord of rat, cat and monkey.