Mizukawa K, Otsuka N, Hattori T
Acta Med Okayama. 1986 Feb;40(1):1-10. doi: 10.18926/AMO/31945.
The ultrastructure of the serotonin (5HT) system in the spinal cord of rats was studied by an immunohistochemical peroxidase-antiperoxidase (PAP) method. Under the light microscope, 5HT immunoreactive staining was observed as brown-colored dots in the anterior horn, lateral horn, posterior horn and pericentral canal region. These positively staining dots were probably indicative of 5HT immunoreactive varicosities and nerve terminals. At the ultrastructural level, 5HT immunoreactive nerve fibers appeared as darkly stained varicosities with PAP positive large electron dense vesicles (80-100 nm), as well as small clear vesicles (30-40 nm) finely coated with PAP immunoreactive products. In the anterior horn, some of the 5HT immunoreactive structures were clearly nerve terminals forming asymmetric synaptic contact with soma or dendrites of the anterior horn cells. In the lateral horn, posterior horn and pericentral canal region, however, only 5HT positive varicosities were detected.
采用免疫组织化学过氧化物酶-抗过氧化物酶（PAP）法研究了大鼠脊髓中5-羟色胺（5HT）系统的超微结构。在光学显微镜下，在前角、侧角、后角和中央管周围区域观察到5HT免疫反应性染色呈棕色点状。这些阳性染色点可能指示5HT免疫反应性曲张体和神经末梢。在超微结构水平上，5HT免疫反应性神经纤维表现为深色染色的曲张体，伴有PAP阳性的大电子致密囊泡（80-100nm），以及少量被PAP免疫反应性产物精细包被的清亮小囊泡（30-40nm）。在前角，一些5HT免疫反应性结构明显是与前角细胞的胞体或树突形成不对称突触接触的神经末梢。然而，在侧角、后角和中央管周围区域，仅检测到5HT阳性曲张体。
